Cool Roofing Technologies
Hashem Akbari Heat Island Group
Ernest Orlando Lawrence Berkeley National Laboratory
Tel 510-486-4287 E_mail H_AkbariLBLgov
httpHeatIslandLBLgov
STEAB Visit to LBNL August 14 2007
2
Orthophoto of Sacramento
3
Under the Canopy Fabric of Sacramento CA
0
10
20
30
40
50
60
70
80
Downtown Industrial Industrial Office Com Com Res
o
f sur
face
are
a
Grass Roofs Pavements Others
Cooling roofs by increasing solar reflectance
bull A conventional dark roof absorbs most sunlight
bull Increasing solar reflectance frac34 reduces solar heat gain frac34 lowers roof temperature
bull High thermal emittance frac34 facilitates radiative cooling frac34 helps keep roof temperature low
bull Lowering roof temperature can reduce frac34 building cooling electricity use frac34 peak power demand
4
frac34 ambient air temperature
Environmental impacts of cooling roofs
bull Benefits frac34 increased human comfort frac34 slowed smog formation frac34 mitigation of urban heat islands in summer frac34 decreased waste from disposal of roofs
bull Penalties frac34 slightly higher wintertime heating energy use frac34 degraded wintertime urban air quality
5
Direct and Indirect Effects of Light-Colored Surfaces
bullDirect Effect - Light-colored roofs reflect solar radiation reduce air-
conditioning use
bullIndirect Effect - Light-colored surfaces in a neighborhood alter surface
energy balance result in lower ambient temperature
6
7
Methodology Energy and Air-Quality Analysis
Slows Reaction
Rates
Cooler Roofs
Cooler Pavements
All Vegetation
Cooler Roofs
Shade Trees
Reduces Outdoor Temps
Lower CO2 NOx and
VOC Levels
Reduces AC Use
Less Energy
Consumed
Reduces Demand at
Power Plants
Area Sources
Emit Less
Direct
Lower Ozone Levels
Indi
rect
Strategies Processes Results
White Roofs Measured Cooling Savings
bull Sacramento 80 in a house 35 in two school bungalows
bull Florida 10-43 in several houses average 19
bull California and Florida 5ndash20 in several commercial buildings
8
Potential National Savings from Changing Roof Reflectivity
Peak Demand Savings in All US $37M
$35M
$16M
$27M $10M $20M $8M
$3M New York $9M $20M
Chicago
$9M
Philadelphia DCBaltimore
Los Angeles
Phoenix DallasFt Worth
Atlanta
Houston Miami New Orleans FtLauderdale
9
ldquoCoolrdquo products for low-sloped roofs
bull Many materials available frac34 coating (white) frac34 single-ply membrane (white) frac34 painted metal (white cool colored)
bull Products are rated by the Cool Roof Rating Council (CRRC) frac34 labels solar reflectance thermal emittance
10
frac34 website wwwcoolroofsorg
Cool Roofing Materials Availability High-Sloped Roofs
bull Limited but expanding material availability frac34 Tile (several maufacturers) frac34 Coatings (one manufacturer) frac34 Metal (many manufacturers) frac34 Shake (only for custom application) frac34 Shingles (one manufacturer)
bull Over 70 of high-sloped roofs use hot asphalt shingles
11
12
ISPLBNL Shingle With Whiter Roofing Granules
13
White is lsquocoolrsquo in Bermuda
14
and in Santorini Greece
15
Cool Roof Technologies
flat white
pitched white
pitched cool amp colored
Old New
16
Cool Colors Reflect Invisible Near-Infrared Sunlight
Cool and Standard Brown Metal Roofing Panels
bull Solar reflectance ~ 02 higher bull Afternoon surface temperature ~ 10ordmC lower
17
Courtesy BASF
Coatings
18
Example Dioxazine Purple Over Various Undercoats
bull Two-layer system frac34 top coat thin layer of dioxazine purple (14-27 microm) frac34 undercoat or substrate
aluminum foil (~ 25 microm) opaque white paint (~1000 microm) non-opaque white paint (~ 25 microm) opaque black paint (~ 25 microm)
purple over
aluminum foil
purple over
opaque white paint
purple over
non-opaque white paint
purple over
opaque black paint
19
Dioxazine Purple Reflectances
over aluminum Rsolar = 041
over opaque white Rsolar = 042
over non-opaque white Rsolar = 030
over opaque black Rsolar = 005
20
National Labs and Industrial Partnership bull Program is sponsored by
CECPIER bull ORNL and LBNL are teaming
with industry bull Broad industrial partnership
bull Industry partners frac34 3M (ganules) frac34 American Roof Tile Coating frac34 BASF (metal) frac34 Custom-Bilt Metals frac34 Elk Manufacturing (shingles) frac34 Ferro frac34 GAF (shingles) frac34 Hanson Roof Tile frac34 ISP Minerals (ganules) frac34 MCA (tiles) frac34 Monier Lifetile (tile) frac34 Shepherd Color Company
Cool and Standard Color-Matched Concrete Tiles
cool Courtesy American Rooftile Coatings
standard
bull Can increase solar reflectance by up to 05 bull Gain greatest for dark colors
∆R=037 ∆R=026 ∆R=023 ∆R=015 ∆R=029 ∆R=029
21
22
Increasing solar reflectance of fiberglass asphalt shingles prototypes
cooler ρ=028
ρ = solar reflectance
ρ=036
warmer ρ=023 ρ=027 ρ=028
ρ=037
23
Increasing solar reflectance of fiberglass asphalt shingles Elk Prestiquereg Cool Color Series
24
Increasing solar reflectance of metal roofing BASF Ultra-Coolreg metal roof coatings
numbers denote solar reflectances cooler (warmer)
Courtesy BASF
Industrial Coatings
25
Cool Metal Roofs
Increasing solar reflectance of clay tiles MCA Clay Tile cool colored tiles
26
Model Color Initial solar reflectance
Solar reflectance after 3 years
Weathered Green Blend
043 049
Natural Red 043 038
Brick Red 042 040
White Buff 068 056
Tobacco 043 041
27
Non-residential building energy and equipment savings15-year net present value of savings ($1000 ft2)
30-year net present value of savings ($1000 ft2) concrete tile roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 39 53 37 56 42 58 39 71 74 60 64 55 68 66 66 60
Energy 406 917 726 992 781 1593 1432 1822 1862 1390 1190 1109 1355 1477 1900 791 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
28
30-year net present value of savings ($1000 ft2) metal roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 41 57 41 61 47 57 48 83 88 65 71 60 73 72 71 65
Energy 495 1053 847 1128 919 1870 1692 2141 2181 1561 1330 1243 1507 1648 2093 918 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
29
Cool Roofs Standards bull Building standards for reflective roofs
- American Society of Heating and Air-conditioning Engineers (ASHRAE) New commercial and residential buildings
- Many state California Georgia Florida Hawaii hellip bull Air quality standards
- South Coast AQMD - SF Bay Area AQMD - EPArsquos SIP (State Implementation Plans)
30
White Roofs Programs in California
bull One Time CEC Incentive -- $20 Million frac34 at $015 to $020 per square foot
bull California utilities incentives bull 2001 to 2005-- credits white and cool colored
roofs bull 2005 requires cool flat roofs bull 2008 may require cool roofs for all buildings
31
Cool Roof Programs around the World
32
bull US bull Europe bull Asia bull Middle East
bull China bull India (Hyderabad
demos see graphs funded by USAID)
Cool Roofs to Save CO2
33
Cool Surfaces also Cool the Globe
bull Cool roof standards are designed to reduce ac demand save money and save emissions In Los Angeles they will eventually save ~$100000 per hour
bull Annual savings in the US = $1-2B ~ 7 M tons CO2
bull Annual savings in the world = $10-15B ~ 100 M tons CO2
bull But higher albedo surfaces (roofs and pavements) directly cool the world (001 K) quite independent of avoided CO2 So we discuss the effect of cool surfaces for tropical temperate cities
34
35
100 Largest Cities have 670 M People
0
1000
2000
3000
4000
5000
0 10 20 30 40
Population (M)
Are
a D
ensi
ty(m
2 per
son)
Mean = 560 m2p Med = 430 m2p
Tokyo
Mexico City New York City Mumbai Satildeo Paulo
Dense Urban Areas are 1 of Land
bull Area of the Earth = 511x1012 m2
bull Land Area (29) = 148x1012 m2 [1] bull Area of the 100 largest cities = 038x1012 m2 = 026
of Land Area for 670 M people bull Assuming 3B live in urban area urban areas =
[3000670] x 026 = 12 of land bull But smaller cities have lower population density
hence urban areas = 2 of land bull Dense developed urban areas only 1 of land [2]
36
Potentials to Increase Urban Albdeo is 01
bull Typical urban area is 25 roof and 35 paved surfaces
bull Roof albedo can increase by 025 for a net change of 025x025=0063
bull Paved surfaces albedo can increase by 015 for a net change of 035x015=0052
bull Net urban area albedo change at least 010
37
Effect of Increasing Urban Albedo by 01
bull Net Change in Global albedo = [CityLand]x[LandGlobe]x∆a = [2]x[1]x∆a = 001 x 029 x01 = 00003 [3]
bull The effect on global temperature frac34 Using three different calculations is about 001K
38
Carbon Equivalency bull Modelers estimate a warming of 2K in 60 years so
003Kyear bull Change of 01 in urban albedo will result in 001K a delay
of ~03 years in global warming bull Worldrsquos current rate of CO2 emissions =
25 G tonsyear (41 tonsyear per person) bull Worldrsquos rate of CO2 emissions averaged over next 60
years = 40 G tonsyear bull Hence 03 years delay is worth 12 Gt CO2 ~ 200 Mt
CO2year
39
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
2
Orthophoto of Sacramento
3
Under the Canopy Fabric of Sacramento CA
0
10
20
30
40
50
60
70
80
Downtown Industrial Industrial Office Com Com Res
o
f sur
face
are
a
Grass Roofs Pavements Others
Cooling roofs by increasing solar reflectance
bull A conventional dark roof absorbs most sunlight
bull Increasing solar reflectance frac34 reduces solar heat gain frac34 lowers roof temperature
bull High thermal emittance frac34 facilitates radiative cooling frac34 helps keep roof temperature low
bull Lowering roof temperature can reduce frac34 building cooling electricity use frac34 peak power demand
4
frac34 ambient air temperature
Environmental impacts of cooling roofs
bull Benefits frac34 increased human comfort frac34 slowed smog formation frac34 mitigation of urban heat islands in summer frac34 decreased waste from disposal of roofs
bull Penalties frac34 slightly higher wintertime heating energy use frac34 degraded wintertime urban air quality
5
Direct and Indirect Effects of Light-Colored Surfaces
bullDirect Effect - Light-colored roofs reflect solar radiation reduce air-
conditioning use
bullIndirect Effect - Light-colored surfaces in a neighborhood alter surface
energy balance result in lower ambient temperature
6
7
Methodology Energy and Air-Quality Analysis
Slows Reaction
Rates
Cooler Roofs
Cooler Pavements
All Vegetation
Cooler Roofs
Shade Trees
Reduces Outdoor Temps
Lower CO2 NOx and
VOC Levels
Reduces AC Use
Less Energy
Consumed
Reduces Demand at
Power Plants
Area Sources
Emit Less
Direct
Lower Ozone Levels
Indi
rect
Strategies Processes Results
White Roofs Measured Cooling Savings
bull Sacramento 80 in a house 35 in two school bungalows
bull Florida 10-43 in several houses average 19
bull California and Florida 5ndash20 in several commercial buildings
8
Potential National Savings from Changing Roof Reflectivity
Peak Demand Savings in All US $37M
$35M
$16M
$27M $10M $20M $8M
$3M New York $9M $20M
Chicago
$9M
Philadelphia DCBaltimore
Los Angeles
Phoenix DallasFt Worth
Atlanta
Houston Miami New Orleans FtLauderdale
9
ldquoCoolrdquo products for low-sloped roofs
bull Many materials available frac34 coating (white) frac34 single-ply membrane (white) frac34 painted metal (white cool colored)
bull Products are rated by the Cool Roof Rating Council (CRRC) frac34 labels solar reflectance thermal emittance
10
frac34 website wwwcoolroofsorg
Cool Roofing Materials Availability High-Sloped Roofs
bull Limited but expanding material availability frac34 Tile (several maufacturers) frac34 Coatings (one manufacturer) frac34 Metal (many manufacturers) frac34 Shake (only for custom application) frac34 Shingles (one manufacturer)
bull Over 70 of high-sloped roofs use hot asphalt shingles
11
12
ISPLBNL Shingle With Whiter Roofing Granules
13
White is lsquocoolrsquo in Bermuda
14
and in Santorini Greece
15
Cool Roof Technologies
flat white
pitched white
pitched cool amp colored
Old New
16
Cool Colors Reflect Invisible Near-Infrared Sunlight
Cool and Standard Brown Metal Roofing Panels
bull Solar reflectance ~ 02 higher bull Afternoon surface temperature ~ 10ordmC lower
17
Courtesy BASF
Coatings
18
Example Dioxazine Purple Over Various Undercoats
bull Two-layer system frac34 top coat thin layer of dioxazine purple (14-27 microm) frac34 undercoat or substrate
aluminum foil (~ 25 microm) opaque white paint (~1000 microm) non-opaque white paint (~ 25 microm) opaque black paint (~ 25 microm)
purple over
aluminum foil
purple over
opaque white paint
purple over
non-opaque white paint
purple over
opaque black paint
19
Dioxazine Purple Reflectances
over aluminum Rsolar = 041
over opaque white Rsolar = 042
over non-opaque white Rsolar = 030
over opaque black Rsolar = 005
20
National Labs and Industrial Partnership bull Program is sponsored by
CECPIER bull ORNL and LBNL are teaming
with industry bull Broad industrial partnership
bull Industry partners frac34 3M (ganules) frac34 American Roof Tile Coating frac34 BASF (metal) frac34 Custom-Bilt Metals frac34 Elk Manufacturing (shingles) frac34 Ferro frac34 GAF (shingles) frac34 Hanson Roof Tile frac34 ISP Minerals (ganules) frac34 MCA (tiles) frac34 Monier Lifetile (tile) frac34 Shepherd Color Company
Cool and Standard Color-Matched Concrete Tiles
cool Courtesy American Rooftile Coatings
standard
bull Can increase solar reflectance by up to 05 bull Gain greatest for dark colors
∆R=037 ∆R=026 ∆R=023 ∆R=015 ∆R=029 ∆R=029
21
22
Increasing solar reflectance of fiberglass asphalt shingles prototypes
cooler ρ=028
ρ = solar reflectance
ρ=036
warmer ρ=023 ρ=027 ρ=028
ρ=037
23
Increasing solar reflectance of fiberglass asphalt shingles Elk Prestiquereg Cool Color Series
24
Increasing solar reflectance of metal roofing BASF Ultra-Coolreg metal roof coatings
numbers denote solar reflectances cooler (warmer)
Courtesy BASF
Industrial Coatings
25
Cool Metal Roofs
Increasing solar reflectance of clay tiles MCA Clay Tile cool colored tiles
26
Model Color Initial solar reflectance
Solar reflectance after 3 years
Weathered Green Blend
043 049
Natural Red 043 038
Brick Red 042 040
White Buff 068 056
Tobacco 043 041
27
Non-residential building energy and equipment savings15-year net present value of savings ($1000 ft2)
30-year net present value of savings ($1000 ft2) concrete tile roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 39 53 37 56 42 58 39 71 74 60 64 55 68 66 66 60
Energy 406 917 726 992 781 1593 1432 1822 1862 1390 1190 1109 1355 1477 1900 791 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
28
30-year net present value of savings ($1000 ft2) metal roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 41 57 41 61 47 57 48 83 88 65 71 60 73 72 71 65
Energy 495 1053 847 1128 919 1870 1692 2141 2181 1561 1330 1243 1507 1648 2093 918 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
29
Cool Roofs Standards bull Building standards for reflective roofs
- American Society of Heating and Air-conditioning Engineers (ASHRAE) New commercial and residential buildings
- Many state California Georgia Florida Hawaii hellip bull Air quality standards
- South Coast AQMD - SF Bay Area AQMD - EPArsquos SIP (State Implementation Plans)
30
White Roofs Programs in California
bull One Time CEC Incentive -- $20 Million frac34 at $015 to $020 per square foot
bull California utilities incentives bull 2001 to 2005-- credits white and cool colored
roofs bull 2005 requires cool flat roofs bull 2008 may require cool roofs for all buildings
31
Cool Roof Programs around the World
32
bull US bull Europe bull Asia bull Middle East
bull China bull India (Hyderabad
demos see graphs funded by USAID)
Cool Roofs to Save CO2
33
Cool Surfaces also Cool the Globe
bull Cool roof standards are designed to reduce ac demand save money and save emissions In Los Angeles they will eventually save ~$100000 per hour
bull Annual savings in the US = $1-2B ~ 7 M tons CO2
bull Annual savings in the world = $10-15B ~ 100 M tons CO2
bull But higher albedo surfaces (roofs and pavements) directly cool the world (001 K) quite independent of avoided CO2 So we discuss the effect of cool surfaces for tropical temperate cities
34
35
100 Largest Cities have 670 M People
0
1000
2000
3000
4000
5000
0 10 20 30 40
Population (M)
Are
a D
ensi
ty(m
2 per
son)
Mean = 560 m2p Med = 430 m2p
Tokyo
Mexico City New York City Mumbai Satildeo Paulo
Dense Urban Areas are 1 of Land
bull Area of the Earth = 511x1012 m2
bull Land Area (29) = 148x1012 m2 [1] bull Area of the 100 largest cities = 038x1012 m2 = 026
of Land Area for 670 M people bull Assuming 3B live in urban area urban areas =
[3000670] x 026 = 12 of land bull But smaller cities have lower population density
hence urban areas = 2 of land bull Dense developed urban areas only 1 of land [2]
36
Potentials to Increase Urban Albdeo is 01
bull Typical urban area is 25 roof and 35 paved surfaces
bull Roof albedo can increase by 025 for a net change of 025x025=0063
bull Paved surfaces albedo can increase by 015 for a net change of 035x015=0052
bull Net urban area albedo change at least 010
37
Effect of Increasing Urban Albedo by 01
bull Net Change in Global albedo = [CityLand]x[LandGlobe]x∆a = [2]x[1]x∆a = 001 x 029 x01 = 00003 [3]
bull The effect on global temperature frac34 Using three different calculations is about 001K
38
Carbon Equivalency bull Modelers estimate a warming of 2K in 60 years so
003Kyear bull Change of 01 in urban albedo will result in 001K a delay
of ~03 years in global warming bull Worldrsquos current rate of CO2 emissions =
25 G tonsyear (41 tonsyear per person) bull Worldrsquos rate of CO2 emissions averaged over next 60
years = 40 G tonsyear bull Hence 03 years delay is worth 12 Gt CO2 ~ 200 Mt
CO2year
39
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
3
Under the Canopy Fabric of Sacramento CA
0
10
20
30
40
50
60
70
80
Downtown Industrial Industrial Office Com Com Res
o
f sur
face
are
a
Grass Roofs Pavements Others
Cooling roofs by increasing solar reflectance
bull A conventional dark roof absorbs most sunlight
bull Increasing solar reflectance frac34 reduces solar heat gain frac34 lowers roof temperature
bull High thermal emittance frac34 facilitates radiative cooling frac34 helps keep roof temperature low
bull Lowering roof temperature can reduce frac34 building cooling electricity use frac34 peak power demand
4
frac34 ambient air temperature
Environmental impacts of cooling roofs
bull Benefits frac34 increased human comfort frac34 slowed smog formation frac34 mitigation of urban heat islands in summer frac34 decreased waste from disposal of roofs
bull Penalties frac34 slightly higher wintertime heating energy use frac34 degraded wintertime urban air quality
5
Direct and Indirect Effects of Light-Colored Surfaces
bullDirect Effect - Light-colored roofs reflect solar radiation reduce air-
conditioning use
bullIndirect Effect - Light-colored surfaces in a neighborhood alter surface
energy balance result in lower ambient temperature
6
7
Methodology Energy and Air-Quality Analysis
Slows Reaction
Rates
Cooler Roofs
Cooler Pavements
All Vegetation
Cooler Roofs
Shade Trees
Reduces Outdoor Temps
Lower CO2 NOx and
VOC Levels
Reduces AC Use
Less Energy
Consumed
Reduces Demand at
Power Plants
Area Sources
Emit Less
Direct
Lower Ozone Levels
Indi
rect
Strategies Processes Results
White Roofs Measured Cooling Savings
bull Sacramento 80 in a house 35 in two school bungalows
bull Florida 10-43 in several houses average 19
bull California and Florida 5ndash20 in several commercial buildings
8
Potential National Savings from Changing Roof Reflectivity
Peak Demand Savings in All US $37M
$35M
$16M
$27M $10M $20M $8M
$3M New York $9M $20M
Chicago
$9M
Philadelphia DCBaltimore
Los Angeles
Phoenix DallasFt Worth
Atlanta
Houston Miami New Orleans FtLauderdale
9
ldquoCoolrdquo products for low-sloped roofs
bull Many materials available frac34 coating (white) frac34 single-ply membrane (white) frac34 painted metal (white cool colored)
bull Products are rated by the Cool Roof Rating Council (CRRC) frac34 labels solar reflectance thermal emittance
10
frac34 website wwwcoolroofsorg
Cool Roofing Materials Availability High-Sloped Roofs
bull Limited but expanding material availability frac34 Tile (several maufacturers) frac34 Coatings (one manufacturer) frac34 Metal (many manufacturers) frac34 Shake (only for custom application) frac34 Shingles (one manufacturer)
bull Over 70 of high-sloped roofs use hot asphalt shingles
11
12
ISPLBNL Shingle With Whiter Roofing Granules
13
White is lsquocoolrsquo in Bermuda
14
and in Santorini Greece
15
Cool Roof Technologies
flat white
pitched white
pitched cool amp colored
Old New
16
Cool Colors Reflect Invisible Near-Infrared Sunlight
Cool and Standard Brown Metal Roofing Panels
bull Solar reflectance ~ 02 higher bull Afternoon surface temperature ~ 10ordmC lower
17
Courtesy BASF
Coatings
18
Example Dioxazine Purple Over Various Undercoats
bull Two-layer system frac34 top coat thin layer of dioxazine purple (14-27 microm) frac34 undercoat or substrate
aluminum foil (~ 25 microm) opaque white paint (~1000 microm) non-opaque white paint (~ 25 microm) opaque black paint (~ 25 microm)
purple over
aluminum foil
purple over
opaque white paint
purple over
non-opaque white paint
purple over
opaque black paint
19
Dioxazine Purple Reflectances
over aluminum Rsolar = 041
over opaque white Rsolar = 042
over non-opaque white Rsolar = 030
over opaque black Rsolar = 005
20
National Labs and Industrial Partnership bull Program is sponsored by
CECPIER bull ORNL and LBNL are teaming
with industry bull Broad industrial partnership
bull Industry partners frac34 3M (ganules) frac34 American Roof Tile Coating frac34 BASF (metal) frac34 Custom-Bilt Metals frac34 Elk Manufacturing (shingles) frac34 Ferro frac34 GAF (shingles) frac34 Hanson Roof Tile frac34 ISP Minerals (ganules) frac34 MCA (tiles) frac34 Monier Lifetile (tile) frac34 Shepherd Color Company
Cool and Standard Color-Matched Concrete Tiles
cool Courtesy American Rooftile Coatings
standard
bull Can increase solar reflectance by up to 05 bull Gain greatest for dark colors
∆R=037 ∆R=026 ∆R=023 ∆R=015 ∆R=029 ∆R=029
21
22
Increasing solar reflectance of fiberglass asphalt shingles prototypes
cooler ρ=028
ρ = solar reflectance
ρ=036
warmer ρ=023 ρ=027 ρ=028
ρ=037
23
Increasing solar reflectance of fiberglass asphalt shingles Elk Prestiquereg Cool Color Series
24
Increasing solar reflectance of metal roofing BASF Ultra-Coolreg metal roof coatings
numbers denote solar reflectances cooler (warmer)
Courtesy BASF
Industrial Coatings
25
Cool Metal Roofs
Increasing solar reflectance of clay tiles MCA Clay Tile cool colored tiles
26
Model Color Initial solar reflectance
Solar reflectance after 3 years
Weathered Green Blend
043 049
Natural Red 043 038
Brick Red 042 040
White Buff 068 056
Tobacco 043 041
27
Non-residential building energy and equipment savings15-year net present value of savings ($1000 ft2)
30-year net present value of savings ($1000 ft2) concrete tile roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 39 53 37 56 42 58 39 71 74 60 64 55 68 66 66 60
Energy 406 917 726 992 781 1593 1432 1822 1862 1390 1190 1109 1355 1477 1900 791 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
28
30-year net present value of savings ($1000 ft2) metal roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 41 57 41 61 47 57 48 83 88 65 71 60 73 72 71 65
Energy 495 1053 847 1128 919 1870 1692 2141 2181 1561 1330 1243 1507 1648 2093 918 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
29
Cool Roofs Standards bull Building standards for reflective roofs
- American Society of Heating and Air-conditioning Engineers (ASHRAE) New commercial and residential buildings
- Many state California Georgia Florida Hawaii hellip bull Air quality standards
- South Coast AQMD - SF Bay Area AQMD - EPArsquos SIP (State Implementation Plans)
30
White Roofs Programs in California
bull One Time CEC Incentive -- $20 Million frac34 at $015 to $020 per square foot
bull California utilities incentives bull 2001 to 2005-- credits white and cool colored
roofs bull 2005 requires cool flat roofs bull 2008 may require cool roofs for all buildings
31
Cool Roof Programs around the World
32
bull US bull Europe bull Asia bull Middle East
bull China bull India (Hyderabad
demos see graphs funded by USAID)
Cool Roofs to Save CO2
33
Cool Surfaces also Cool the Globe
bull Cool roof standards are designed to reduce ac demand save money and save emissions In Los Angeles they will eventually save ~$100000 per hour
bull Annual savings in the US = $1-2B ~ 7 M tons CO2
bull Annual savings in the world = $10-15B ~ 100 M tons CO2
bull But higher albedo surfaces (roofs and pavements) directly cool the world (001 K) quite independent of avoided CO2 So we discuss the effect of cool surfaces for tropical temperate cities
34
35
100 Largest Cities have 670 M People
0
1000
2000
3000
4000
5000
0 10 20 30 40
Population (M)
Are
a D
ensi
ty(m
2 per
son)
Mean = 560 m2p Med = 430 m2p
Tokyo
Mexico City New York City Mumbai Satildeo Paulo
Dense Urban Areas are 1 of Land
bull Area of the Earth = 511x1012 m2
bull Land Area (29) = 148x1012 m2 [1] bull Area of the 100 largest cities = 038x1012 m2 = 026
of Land Area for 670 M people bull Assuming 3B live in urban area urban areas =
[3000670] x 026 = 12 of land bull But smaller cities have lower population density
hence urban areas = 2 of land bull Dense developed urban areas only 1 of land [2]
36
Potentials to Increase Urban Albdeo is 01
bull Typical urban area is 25 roof and 35 paved surfaces
bull Roof albedo can increase by 025 for a net change of 025x025=0063
bull Paved surfaces albedo can increase by 015 for a net change of 035x015=0052
bull Net urban area albedo change at least 010
37
Effect of Increasing Urban Albedo by 01
bull Net Change in Global albedo = [CityLand]x[LandGlobe]x∆a = [2]x[1]x∆a = 001 x 029 x01 = 00003 [3]
bull The effect on global temperature frac34 Using three different calculations is about 001K
38
Carbon Equivalency bull Modelers estimate a warming of 2K in 60 years so
003Kyear bull Change of 01 in urban albedo will result in 001K a delay
of ~03 years in global warming bull Worldrsquos current rate of CO2 emissions =
25 G tonsyear (41 tonsyear per person) bull Worldrsquos rate of CO2 emissions averaged over next 60
years = 40 G tonsyear bull Hence 03 years delay is worth 12 Gt CO2 ~ 200 Mt
CO2year
39
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
Cooling roofs by increasing solar reflectance
bull A conventional dark roof absorbs most sunlight
bull Increasing solar reflectance frac34 reduces solar heat gain frac34 lowers roof temperature
bull High thermal emittance frac34 facilitates radiative cooling frac34 helps keep roof temperature low
bull Lowering roof temperature can reduce frac34 building cooling electricity use frac34 peak power demand
4
frac34 ambient air temperature
Environmental impacts of cooling roofs
bull Benefits frac34 increased human comfort frac34 slowed smog formation frac34 mitigation of urban heat islands in summer frac34 decreased waste from disposal of roofs
bull Penalties frac34 slightly higher wintertime heating energy use frac34 degraded wintertime urban air quality
5
Direct and Indirect Effects of Light-Colored Surfaces
bullDirect Effect - Light-colored roofs reflect solar radiation reduce air-
conditioning use
bullIndirect Effect - Light-colored surfaces in a neighborhood alter surface
energy balance result in lower ambient temperature
6
7
Methodology Energy and Air-Quality Analysis
Slows Reaction
Rates
Cooler Roofs
Cooler Pavements
All Vegetation
Cooler Roofs
Shade Trees
Reduces Outdoor Temps
Lower CO2 NOx and
VOC Levels
Reduces AC Use
Less Energy
Consumed
Reduces Demand at
Power Plants
Area Sources
Emit Less
Direct
Lower Ozone Levels
Indi
rect
Strategies Processes Results
White Roofs Measured Cooling Savings
bull Sacramento 80 in a house 35 in two school bungalows
bull Florida 10-43 in several houses average 19
bull California and Florida 5ndash20 in several commercial buildings
8
Potential National Savings from Changing Roof Reflectivity
Peak Demand Savings in All US $37M
$35M
$16M
$27M $10M $20M $8M
$3M New York $9M $20M
Chicago
$9M
Philadelphia DCBaltimore
Los Angeles
Phoenix DallasFt Worth
Atlanta
Houston Miami New Orleans FtLauderdale
9
ldquoCoolrdquo products for low-sloped roofs
bull Many materials available frac34 coating (white) frac34 single-ply membrane (white) frac34 painted metal (white cool colored)
bull Products are rated by the Cool Roof Rating Council (CRRC) frac34 labels solar reflectance thermal emittance
10
frac34 website wwwcoolroofsorg
Cool Roofing Materials Availability High-Sloped Roofs
bull Limited but expanding material availability frac34 Tile (several maufacturers) frac34 Coatings (one manufacturer) frac34 Metal (many manufacturers) frac34 Shake (only for custom application) frac34 Shingles (one manufacturer)
bull Over 70 of high-sloped roofs use hot asphalt shingles
11
12
ISPLBNL Shingle With Whiter Roofing Granules
13
White is lsquocoolrsquo in Bermuda
14
and in Santorini Greece
15
Cool Roof Technologies
flat white
pitched white
pitched cool amp colored
Old New
16
Cool Colors Reflect Invisible Near-Infrared Sunlight
Cool and Standard Brown Metal Roofing Panels
bull Solar reflectance ~ 02 higher bull Afternoon surface temperature ~ 10ordmC lower
17
Courtesy BASF
Coatings
18
Example Dioxazine Purple Over Various Undercoats
bull Two-layer system frac34 top coat thin layer of dioxazine purple (14-27 microm) frac34 undercoat or substrate
aluminum foil (~ 25 microm) opaque white paint (~1000 microm) non-opaque white paint (~ 25 microm) opaque black paint (~ 25 microm)
purple over
aluminum foil
purple over
opaque white paint
purple over
non-opaque white paint
purple over
opaque black paint
19
Dioxazine Purple Reflectances
over aluminum Rsolar = 041
over opaque white Rsolar = 042
over non-opaque white Rsolar = 030
over opaque black Rsolar = 005
20
National Labs and Industrial Partnership bull Program is sponsored by
CECPIER bull ORNL and LBNL are teaming
with industry bull Broad industrial partnership
bull Industry partners frac34 3M (ganules) frac34 American Roof Tile Coating frac34 BASF (metal) frac34 Custom-Bilt Metals frac34 Elk Manufacturing (shingles) frac34 Ferro frac34 GAF (shingles) frac34 Hanson Roof Tile frac34 ISP Minerals (ganules) frac34 MCA (tiles) frac34 Monier Lifetile (tile) frac34 Shepherd Color Company
Cool and Standard Color-Matched Concrete Tiles
cool Courtesy American Rooftile Coatings
standard
bull Can increase solar reflectance by up to 05 bull Gain greatest for dark colors
∆R=037 ∆R=026 ∆R=023 ∆R=015 ∆R=029 ∆R=029
21
22
Increasing solar reflectance of fiberglass asphalt shingles prototypes
cooler ρ=028
ρ = solar reflectance
ρ=036
warmer ρ=023 ρ=027 ρ=028
ρ=037
23
Increasing solar reflectance of fiberglass asphalt shingles Elk Prestiquereg Cool Color Series
24
Increasing solar reflectance of metal roofing BASF Ultra-Coolreg metal roof coatings
numbers denote solar reflectances cooler (warmer)
Courtesy BASF
Industrial Coatings
25
Cool Metal Roofs
Increasing solar reflectance of clay tiles MCA Clay Tile cool colored tiles
26
Model Color Initial solar reflectance
Solar reflectance after 3 years
Weathered Green Blend
043 049
Natural Red 043 038
Brick Red 042 040
White Buff 068 056
Tobacco 043 041
27
Non-residential building energy and equipment savings15-year net present value of savings ($1000 ft2)
30-year net present value of savings ($1000 ft2) concrete tile roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 39 53 37 56 42 58 39 71 74 60 64 55 68 66 66 60
Energy 406 917 726 992 781 1593 1432 1822 1862 1390 1190 1109 1355 1477 1900 791 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
28
30-year net present value of savings ($1000 ft2) metal roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 41 57 41 61 47 57 48 83 88 65 71 60 73 72 71 65
Energy 495 1053 847 1128 919 1870 1692 2141 2181 1561 1330 1243 1507 1648 2093 918 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
29
Cool Roofs Standards bull Building standards for reflective roofs
- American Society of Heating and Air-conditioning Engineers (ASHRAE) New commercial and residential buildings
- Many state California Georgia Florida Hawaii hellip bull Air quality standards
- South Coast AQMD - SF Bay Area AQMD - EPArsquos SIP (State Implementation Plans)
30
White Roofs Programs in California
bull One Time CEC Incentive -- $20 Million frac34 at $015 to $020 per square foot
bull California utilities incentives bull 2001 to 2005-- credits white and cool colored
roofs bull 2005 requires cool flat roofs bull 2008 may require cool roofs for all buildings
31
Cool Roof Programs around the World
32
bull US bull Europe bull Asia bull Middle East
bull China bull India (Hyderabad
demos see graphs funded by USAID)
Cool Roofs to Save CO2
33
Cool Surfaces also Cool the Globe
bull Cool roof standards are designed to reduce ac demand save money and save emissions In Los Angeles they will eventually save ~$100000 per hour
bull Annual savings in the US = $1-2B ~ 7 M tons CO2
bull Annual savings in the world = $10-15B ~ 100 M tons CO2
bull But higher albedo surfaces (roofs and pavements) directly cool the world (001 K) quite independent of avoided CO2 So we discuss the effect of cool surfaces for tropical temperate cities
34
35
100 Largest Cities have 670 M People
0
1000
2000
3000
4000
5000
0 10 20 30 40
Population (M)
Are
a D
ensi
ty(m
2 per
son)
Mean = 560 m2p Med = 430 m2p
Tokyo
Mexico City New York City Mumbai Satildeo Paulo
Dense Urban Areas are 1 of Land
bull Area of the Earth = 511x1012 m2
bull Land Area (29) = 148x1012 m2 [1] bull Area of the 100 largest cities = 038x1012 m2 = 026
of Land Area for 670 M people bull Assuming 3B live in urban area urban areas =
[3000670] x 026 = 12 of land bull But smaller cities have lower population density
hence urban areas = 2 of land bull Dense developed urban areas only 1 of land [2]
36
Potentials to Increase Urban Albdeo is 01
bull Typical urban area is 25 roof and 35 paved surfaces
bull Roof albedo can increase by 025 for a net change of 025x025=0063
bull Paved surfaces albedo can increase by 015 for a net change of 035x015=0052
bull Net urban area albedo change at least 010
37
Effect of Increasing Urban Albedo by 01
bull Net Change in Global albedo = [CityLand]x[LandGlobe]x∆a = [2]x[1]x∆a = 001 x 029 x01 = 00003 [3]
bull The effect on global temperature frac34 Using three different calculations is about 001K
38
Carbon Equivalency bull Modelers estimate a warming of 2K in 60 years so
003Kyear bull Change of 01 in urban albedo will result in 001K a delay
of ~03 years in global warming bull Worldrsquos current rate of CO2 emissions =
25 G tonsyear (41 tonsyear per person) bull Worldrsquos rate of CO2 emissions averaged over next 60
years = 40 G tonsyear bull Hence 03 years delay is worth 12 Gt CO2 ~ 200 Mt
CO2year
39
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
Environmental impacts of cooling roofs
bull Benefits frac34 increased human comfort frac34 slowed smog formation frac34 mitigation of urban heat islands in summer frac34 decreased waste from disposal of roofs
bull Penalties frac34 slightly higher wintertime heating energy use frac34 degraded wintertime urban air quality
5
Direct and Indirect Effects of Light-Colored Surfaces
bullDirect Effect - Light-colored roofs reflect solar radiation reduce air-
conditioning use
bullIndirect Effect - Light-colored surfaces in a neighborhood alter surface
energy balance result in lower ambient temperature
6
7
Methodology Energy and Air-Quality Analysis
Slows Reaction
Rates
Cooler Roofs
Cooler Pavements
All Vegetation
Cooler Roofs
Shade Trees
Reduces Outdoor Temps
Lower CO2 NOx and
VOC Levels
Reduces AC Use
Less Energy
Consumed
Reduces Demand at
Power Plants
Area Sources
Emit Less
Direct
Lower Ozone Levels
Indi
rect
Strategies Processes Results
White Roofs Measured Cooling Savings
bull Sacramento 80 in a house 35 in two school bungalows
bull Florida 10-43 in several houses average 19
bull California and Florida 5ndash20 in several commercial buildings
8
Potential National Savings from Changing Roof Reflectivity
Peak Demand Savings in All US $37M
$35M
$16M
$27M $10M $20M $8M
$3M New York $9M $20M
Chicago
$9M
Philadelphia DCBaltimore
Los Angeles
Phoenix DallasFt Worth
Atlanta
Houston Miami New Orleans FtLauderdale
9
ldquoCoolrdquo products for low-sloped roofs
bull Many materials available frac34 coating (white) frac34 single-ply membrane (white) frac34 painted metal (white cool colored)
bull Products are rated by the Cool Roof Rating Council (CRRC) frac34 labels solar reflectance thermal emittance
10
frac34 website wwwcoolroofsorg
Cool Roofing Materials Availability High-Sloped Roofs
bull Limited but expanding material availability frac34 Tile (several maufacturers) frac34 Coatings (one manufacturer) frac34 Metal (many manufacturers) frac34 Shake (only for custom application) frac34 Shingles (one manufacturer)
bull Over 70 of high-sloped roofs use hot asphalt shingles
11
12
ISPLBNL Shingle With Whiter Roofing Granules
13
White is lsquocoolrsquo in Bermuda
14
and in Santorini Greece
15
Cool Roof Technologies
flat white
pitched white
pitched cool amp colored
Old New
16
Cool Colors Reflect Invisible Near-Infrared Sunlight
Cool and Standard Brown Metal Roofing Panels
bull Solar reflectance ~ 02 higher bull Afternoon surface temperature ~ 10ordmC lower
17
Courtesy BASF
Coatings
18
Example Dioxazine Purple Over Various Undercoats
bull Two-layer system frac34 top coat thin layer of dioxazine purple (14-27 microm) frac34 undercoat or substrate
aluminum foil (~ 25 microm) opaque white paint (~1000 microm) non-opaque white paint (~ 25 microm) opaque black paint (~ 25 microm)
purple over
aluminum foil
purple over
opaque white paint
purple over
non-opaque white paint
purple over
opaque black paint
19
Dioxazine Purple Reflectances
over aluminum Rsolar = 041
over opaque white Rsolar = 042
over non-opaque white Rsolar = 030
over opaque black Rsolar = 005
20
National Labs and Industrial Partnership bull Program is sponsored by
CECPIER bull ORNL and LBNL are teaming
with industry bull Broad industrial partnership
bull Industry partners frac34 3M (ganules) frac34 American Roof Tile Coating frac34 BASF (metal) frac34 Custom-Bilt Metals frac34 Elk Manufacturing (shingles) frac34 Ferro frac34 GAF (shingles) frac34 Hanson Roof Tile frac34 ISP Minerals (ganules) frac34 MCA (tiles) frac34 Monier Lifetile (tile) frac34 Shepherd Color Company
Cool and Standard Color-Matched Concrete Tiles
cool Courtesy American Rooftile Coatings
standard
bull Can increase solar reflectance by up to 05 bull Gain greatest for dark colors
∆R=037 ∆R=026 ∆R=023 ∆R=015 ∆R=029 ∆R=029
21
22
Increasing solar reflectance of fiberglass asphalt shingles prototypes
cooler ρ=028
ρ = solar reflectance
ρ=036
warmer ρ=023 ρ=027 ρ=028
ρ=037
23
Increasing solar reflectance of fiberglass asphalt shingles Elk Prestiquereg Cool Color Series
24
Increasing solar reflectance of metal roofing BASF Ultra-Coolreg metal roof coatings
numbers denote solar reflectances cooler (warmer)
Courtesy BASF
Industrial Coatings
25
Cool Metal Roofs
Increasing solar reflectance of clay tiles MCA Clay Tile cool colored tiles
26
Model Color Initial solar reflectance
Solar reflectance after 3 years
Weathered Green Blend
043 049
Natural Red 043 038
Brick Red 042 040
White Buff 068 056
Tobacco 043 041
27
Non-residential building energy and equipment savings15-year net present value of savings ($1000 ft2)
30-year net present value of savings ($1000 ft2) concrete tile roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 39 53 37 56 42 58 39 71 74 60 64 55 68 66 66 60
Energy 406 917 726 992 781 1593 1432 1822 1862 1390 1190 1109 1355 1477 1900 791 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
28
30-year net present value of savings ($1000 ft2) metal roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 41 57 41 61 47 57 48 83 88 65 71 60 73 72 71 65
Energy 495 1053 847 1128 919 1870 1692 2141 2181 1561 1330 1243 1507 1648 2093 918 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
29
Cool Roofs Standards bull Building standards for reflective roofs
- American Society of Heating and Air-conditioning Engineers (ASHRAE) New commercial and residential buildings
- Many state California Georgia Florida Hawaii hellip bull Air quality standards
- South Coast AQMD - SF Bay Area AQMD - EPArsquos SIP (State Implementation Plans)
30
White Roofs Programs in California
bull One Time CEC Incentive -- $20 Million frac34 at $015 to $020 per square foot
bull California utilities incentives bull 2001 to 2005-- credits white and cool colored
roofs bull 2005 requires cool flat roofs bull 2008 may require cool roofs for all buildings
31
Cool Roof Programs around the World
32
bull US bull Europe bull Asia bull Middle East
bull China bull India (Hyderabad
demos see graphs funded by USAID)
Cool Roofs to Save CO2
33
Cool Surfaces also Cool the Globe
bull Cool roof standards are designed to reduce ac demand save money and save emissions In Los Angeles they will eventually save ~$100000 per hour
bull Annual savings in the US = $1-2B ~ 7 M tons CO2
bull Annual savings in the world = $10-15B ~ 100 M tons CO2
bull But higher albedo surfaces (roofs and pavements) directly cool the world (001 K) quite independent of avoided CO2 So we discuss the effect of cool surfaces for tropical temperate cities
34
35
100 Largest Cities have 670 M People
0
1000
2000
3000
4000
5000
0 10 20 30 40
Population (M)
Are
a D
ensi
ty(m
2 per
son)
Mean = 560 m2p Med = 430 m2p
Tokyo
Mexico City New York City Mumbai Satildeo Paulo
Dense Urban Areas are 1 of Land
bull Area of the Earth = 511x1012 m2
bull Land Area (29) = 148x1012 m2 [1] bull Area of the 100 largest cities = 038x1012 m2 = 026
of Land Area for 670 M people bull Assuming 3B live in urban area urban areas =
[3000670] x 026 = 12 of land bull But smaller cities have lower population density
hence urban areas = 2 of land bull Dense developed urban areas only 1 of land [2]
36
Potentials to Increase Urban Albdeo is 01
bull Typical urban area is 25 roof and 35 paved surfaces
bull Roof albedo can increase by 025 for a net change of 025x025=0063
bull Paved surfaces albedo can increase by 015 for a net change of 035x015=0052
bull Net urban area albedo change at least 010
37
Effect of Increasing Urban Albedo by 01
bull Net Change in Global albedo = [CityLand]x[LandGlobe]x∆a = [2]x[1]x∆a = 001 x 029 x01 = 00003 [3]
bull The effect on global temperature frac34 Using three different calculations is about 001K
38
Carbon Equivalency bull Modelers estimate a warming of 2K in 60 years so
003Kyear bull Change of 01 in urban albedo will result in 001K a delay
of ~03 years in global warming bull Worldrsquos current rate of CO2 emissions =
25 G tonsyear (41 tonsyear per person) bull Worldrsquos rate of CO2 emissions averaged over next 60
years = 40 G tonsyear bull Hence 03 years delay is worth 12 Gt CO2 ~ 200 Mt
CO2year
39
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
Direct and Indirect Effects of Light-Colored Surfaces
bullDirect Effect - Light-colored roofs reflect solar radiation reduce air-
conditioning use
bullIndirect Effect - Light-colored surfaces in a neighborhood alter surface
energy balance result in lower ambient temperature
6
7
Methodology Energy and Air-Quality Analysis
Slows Reaction
Rates
Cooler Roofs
Cooler Pavements
All Vegetation
Cooler Roofs
Shade Trees
Reduces Outdoor Temps
Lower CO2 NOx and
VOC Levels
Reduces AC Use
Less Energy
Consumed
Reduces Demand at
Power Plants
Area Sources
Emit Less
Direct
Lower Ozone Levels
Indi
rect
Strategies Processes Results
White Roofs Measured Cooling Savings
bull Sacramento 80 in a house 35 in two school bungalows
bull Florida 10-43 in several houses average 19
bull California and Florida 5ndash20 in several commercial buildings
8
Potential National Savings from Changing Roof Reflectivity
Peak Demand Savings in All US $37M
$35M
$16M
$27M $10M $20M $8M
$3M New York $9M $20M
Chicago
$9M
Philadelphia DCBaltimore
Los Angeles
Phoenix DallasFt Worth
Atlanta
Houston Miami New Orleans FtLauderdale
9
ldquoCoolrdquo products for low-sloped roofs
bull Many materials available frac34 coating (white) frac34 single-ply membrane (white) frac34 painted metal (white cool colored)
bull Products are rated by the Cool Roof Rating Council (CRRC) frac34 labels solar reflectance thermal emittance
10
frac34 website wwwcoolroofsorg
Cool Roofing Materials Availability High-Sloped Roofs
bull Limited but expanding material availability frac34 Tile (several maufacturers) frac34 Coatings (one manufacturer) frac34 Metal (many manufacturers) frac34 Shake (only for custom application) frac34 Shingles (one manufacturer)
bull Over 70 of high-sloped roofs use hot asphalt shingles
11
12
ISPLBNL Shingle With Whiter Roofing Granules
13
White is lsquocoolrsquo in Bermuda
14
and in Santorini Greece
15
Cool Roof Technologies
flat white
pitched white
pitched cool amp colored
Old New
16
Cool Colors Reflect Invisible Near-Infrared Sunlight
Cool and Standard Brown Metal Roofing Panels
bull Solar reflectance ~ 02 higher bull Afternoon surface temperature ~ 10ordmC lower
17
Courtesy BASF
Coatings
18
Example Dioxazine Purple Over Various Undercoats
bull Two-layer system frac34 top coat thin layer of dioxazine purple (14-27 microm) frac34 undercoat or substrate
aluminum foil (~ 25 microm) opaque white paint (~1000 microm) non-opaque white paint (~ 25 microm) opaque black paint (~ 25 microm)
purple over
aluminum foil
purple over
opaque white paint
purple over
non-opaque white paint
purple over
opaque black paint
19
Dioxazine Purple Reflectances
over aluminum Rsolar = 041
over opaque white Rsolar = 042
over non-opaque white Rsolar = 030
over opaque black Rsolar = 005
20
National Labs and Industrial Partnership bull Program is sponsored by
CECPIER bull ORNL and LBNL are teaming
with industry bull Broad industrial partnership
bull Industry partners frac34 3M (ganules) frac34 American Roof Tile Coating frac34 BASF (metal) frac34 Custom-Bilt Metals frac34 Elk Manufacturing (shingles) frac34 Ferro frac34 GAF (shingles) frac34 Hanson Roof Tile frac34 ISP Minerals (ganules) frac34 MCA (tiles) frac34 Monier Lifetile (tile) frac34 Shepherd Color Company
Cool and Standard Color-Matched Concrete Tiles
cool Courtesy American Rooftile Coatings
standard
bull Can increase solar reflectance by up to 05 bull Gain greatest for dark colors
∆R=037 ∆R=026 ∆R=023 ∆R=015 ∆R=029 ∆R=029
21
22
Increasing solar reflectance of fiberglass asphalt shingles prototypes
cooler ρ=028
ρ = solar reflectance
ρ=036
warmer ρ=023 ρ=027 ρ=028
ρ=037
23
Increasing solar reflectance of fiberglass asphalt shingles Elk Prestiquereg Cool Color Series
24
Increasing solar reflectance of metal roofing BASF Ultra-Coolreg metal roof coatings
numbers denote solar reflectances cooler (warmer)
Courtesy BASF
Industrial Coatings
25
Cool Metal Roofs
Increasing solar reflectance of clay tiles MCA Clay Tile cool colored tiles
26
Model Color Initial solar reflectance
Solar reflectance after 3 years
Weathered Green Blend
043 049
Natural Red 043 038
Brick Red 042 040
White Buff 068 056
Tobacco 043 041
27
Non-residential building energy and equipment savings15-year net present value of savings ($1000 ft2)
30-year net present value of savings ($1000 ft2) concrete tile roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 39 53 37 56 42 58 39 71 74 60 64 55 68 66 66 60
Energy 406 917 726 992 781 1593 1432 1822 1862 1390 1190 1109 1355 1477 1900 791 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
28
30-year net present value of savings ($1000 ft2) metal roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 41 57 41 61 47 57 48 83 88 65 71 60 73 72 71 65
Energy 495 1053 847 1128 919 1870 1692 2141 2181 1561 1330 1243 1507 1648 2093 918 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
29
Cool Roofs Standards bull Building standards for reflective roofs
- American Society of Heating and Air-conditioning Engineers (ASHRAE) New commercial and residential buildings
- Many state California Georgia Florida Hawaii hellip bull Air quality standards
- South Coast AQMD - SF Bay Area AQMD - EPArsquos SIP (State Implementation Plans)
30
White Roofs Programs in California
bull One Time CEC Incentive -- $20 Million frac34 at $015 to $020 per square foot
bull California utilities incentives bull 2001 to 2005-- credits white and cool colored
roofs bull 2005 requires cool flat roofs bull 2008 may require cool roofs for all buildings
31
Cool Roof Programs around the World
32
bull US bull Europe bull Asia bull Middle East
bull China bull India (Hyderabad
demos see graphs funded by USAID)
Cool Roofs to Save CO2
33
Cool Surfaces also Cool the Globe
bull Cool roof standards are designed to reduce ac demand save money and save emissions In Los Angeles they will eventually save ~$100000 per hour
bull Annual savings in the US = $1-2B ~ 7 M tons CO2
bull Annual savings in the world = $10-15B ~ 100 M tons CO2
bull But higher albedo surfaces (roofs and pavements) directly cool the world (001 K) quite independent of avoided CO2 So we discuss the effect of cool surfaces for tropical temperate cities
34
35
100 Largest Cities have 670 M People
0
1000
2000
3000
4000
5000
0 10 20 30 40
Population (M)
Are
a D
ensi
ty(m
2 per
son)
Mean = 560 m2p Med = 430 m2p
Tokyo
Mexico City New York City Mumbai Satildeo Paulo
Dense Urban Areas are 1 of Land
bull Area of the Earth = 511x1012 m2
bull Land Area (29) = 148x1012 m2 [1] bull Area of the 100 largest cities = 038x1012 m2 = 026
of Land Area for 670 M people bull Assuming 3B live in urban area urban areas =
[3000670] x 026 = 12 of land bull But smaller cities have lower population density
hence urban areas = 2 of land bull Dense developed urban areas only 1 of land [2]
36
Potentials to Increase Urban Albdeo is 01
bull Typical urban area is 25 roof and 35 paved surfaces
bull Roof albedo can increase by 025 for a net change of 025x025=0063
bull Paved surfaces albedo can increase by 015 for a net change of 035x015=0052
bull Net urban area albedo change at least 010
37
Effect of Increasing Urban Albedo by 01
bull Net Change in Global albedo = [CityLand]x[LandGlobe]x∆a = [2]x[1]x∆a = 001 x 029 x01 = 00003 [3]
bull The effect on global temperature frac34 Using three different calculations is about 001K
38
Carbon Equivalency bull Modelers estimate a warming of 2K in 60 years so
003Kyear bull Change of 01 in urban albedo will result in 001K a delay
of ~03 years in global warming bull Worldrsquos current rate of CO2 emissions =
25 G tonsyear (41 tonsyear per person) bull Worldrsquos rate of CO2 emissions averaged over next 60
years = 40 G tonsyear bull Hence 03 years delay is worth 12 Gt CO2 ~ 200 Mt
CO2year
39
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
7
Methodology Energy and Air-Quality Analysis
Slows Reaction
Rates
Cooler Roofs
Cooler Pavements
All Vegetation
Cooler Roofs
Shade Trees
Reduces Outdoor Temps
Lower CO2 NOx and
VOC Levels
Reduces AC Use
Less Energy
Consumed
Reduces Demand at
Power Plants
Area Sources
Emit Less
Direct
Lower Ozone Levels
Indi
rect
Strategies Processes Results
White Roofs Measured Cooling Savings
bull Sacramento 80 in a house 35 in two school bungalows
bull Florida 10-43 in several houses average 19
bull California and Florida 5ndash20 in several commercial buildings
8
Potential National Savings from Changing Roof Reflectivity
Peak Demand Savings in All US $37M
$35M
$16M
$27M $10M $20M $8M
$3M New York $9M $20M
Chicago
$9M
Philadelphia DCBaltimore
Los Angeles
Phoenix DallasFt Worth
Atlanta
Houston Miami New Orleans FtLauderdale
9
ldquoCoolrdquo products for low-sloped roofs
bull Many materials available frac34 coating (white) frac34 single-ply membrane (white) frac34 painted metal (white cool colored)
bull Products are rated by the Cool Roof Rating Council (CRRC) frac34 labels solar reflectance thermal emittance
10
frac34 website wwwcoolroofsorg
Cool Roofing Materials Availability High-Sloped Roofs
bull Limited but expanding material availability frac34 Tile (several maufacturers) frac34 Coatings (one manufacturer) frac34 Metal (many manufacturers) frac34 Shake (only for custom application) frac34 Shingles (one manufacturer)
bull Over 70 of high-sloped roofs use hot asphalt shingles
11
12
ISPLBNL Shingle With Whiter Roofing Granules
13
White is lsquocoolrsquo in Bermuda
14
and in Santorini Greece
15
Cool Roof Technologies
flat white
pitched white
pitched cool amp colored
Old New
16
Cool Colors Reflect Invisible Near-Infrared Sunlight
Cool and Standard Brown Metal Roofing Panels
bull Solar reflectance ~ 02 higher bull Afternoon surface temperature ~ 10ordmC lower
17
Courtesy BASF
Coatings
18
Example Dioxazine Purple Over Various Undercoats
bull Two-layer system frac34 top coat thin layer of dioxazine purple (14-27 microm) frac34 undercoat or substrate
aluminum foil (~ 25 microm) opaque white paint (~1000 microm) non-opaque white paint (~ 25 microm) opaque black paint (~ 25 microm)
purple over
aluminum foil
purple over
opaque white paint
purple over
non-opaque white paint
purple over
opaque black paint
19
Dioxazine Purple Reflectances
over aluminum Rsolar = 041
over opaque white Rsolar = 042
over non-opaque white Rsolar = 030
over opaque black Rsolar = 005
20
National Labs and Industrial Partnership bull Program is sponsored by
CECPIER bull ORNL and LBNL are teaming
with industry bull Broad industrial partnership
bull Industry partners frac34 3M (ganules) frac34 American Roof Tile Coating frac34 BASF (metal) frac34 Custom-Bilt Metals frac34 Elk Manufacturing (shingles) frac34 Ferro frac34 GAF (shingles) frac34 Hanson Roof Tile frac34 ISP Minerals (ganules) frac34 MCA (tiles) frac34 Monier Lifetile (tile) frac34 Shepherd Color Company
Cool and Standard Color-Matched Concrete Tiles
cool Courtesy American Rooftile Coatings
standard
bull Can increase solar reflectance by up to 05 bull Gain greatest for dark colors
∆R=037 ∆R=026 ∆R=023 ∆R=015 ∆R=029 ∆R=029
21
22
Increasing solar reflectance of fiberglass asphalt shingles prototypes
cooler ρ=028
ρ = solar reflectance
ρ=036
warmer ρ=023 ρ=027 ρ=028
ρ=037
23
Increasing solar reflectance of fiberglass asphalt shingles Elk Prestiquereg Cool Color Series
24
Increasing solar reflectance of metal roofing BASF Ultra-Coolreg metal roof coatings
numbers denote solar reflectances cooler (warmer)
Courtesy BASF
Industrial Coatings
25
Cool Metal Roofs
Increasing solar reflectance of clay tiles MCA Clay Tile cool colored tiles
26
Model Color Initial solar reflectance
Solar reflectance after 3 years
Weathered Green Blend
043 049
Natural Red 043 038
Brick Red 042 040
White Buff 068 056
Tobacco 043 041
27
Non-residential building energy and equipment savings15-year net present value of savings ($1000 ft2)
30-year net present value of savings ($1000 ft2) concrete tile roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 39 53 37 56 42 58 39 71 74 60 64 55 68 66 66 60
Energy 406 917 726 992 781 1593 1432 1822 1862 1390 1190 1109 1355 1477 1900 791 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
28
30-year net present value of savings ($1000 ft2) metal roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 41 57 41 61 47 57 48 83 88 65 71 60 73 72 71 65
Energy 495 1053 847 1128 919 1870 1692 2141 2181 1561 1330 1243 1507 1648 2093 918 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
29
Cool Roofs Standards bull Building standards for reflective roofs
- American Society of Heating and Air-conditioning Engineers (ASHRAE) New commercial and residential buildings
- Many state California Georgia Florida Hawaii hellip bull Air quality standards
- South Coast AQMD - SF Bay Area AQMD - EPArsquos SIP (State Implementation Plans)
30
White Roofs Programs in California
bull One Time CEC Incentive -- $20 Million frac34 at $015 to $020 per square foot
bull California utilities incentives bull 2001 to 2005-- credits white and cool colored
roofs bull 2005 requires cool flat roofs bull 2008 may require cool roofs for all buildings
31
Cool Roof Programs around the World
32
bull US bull Europe bull Asia bull Middle East
bull China bull India (Hyderabad
demos see graphs funded by USAID)
Cool Roofs to Save CO2
33
Cool Surfaces also Cool the Globe
bull Cool roof standards are designed to reduce ac demand save money and save emissions In Los Angeles they will eventually save ~$100000 per hour
bull Annual savings in the US = $1-2B ~ 7 M tons CO2
bull Annual savings in the world = $10-15B ~ 100 M tons CO2
bull But higher albedo surfaces (roofs and pavements) directly cool the world (001 K) quite independent of avoided CO2 So we discuss the effect of cool surfaces for tropical temperate cities
34
35
100 Largest Cities have 670 M People
0
1000
2000
3000
4000
5000
0 10 20 30 40
Population (M)
Are
a D
ensi
ty(m
2 per
son)
Mean = 560 m2p Med = 430 m2p
Tokyo
Mexico City New York City Mumbai Satildeo Paulo
Dense Urban Areas are 1 of Land
bull Area of the Earth = 511x1012 m2
bull Land Area (29) = 148x1012 m2 [1] bull Area of the 100 largest cities = 038x1012 m2 = 026
of Land Area for 670 M people bull Assuming 3B live in urban area urban areas =
[3000670] x 026 = 12 of land bull But smaller cities have lower population density
hence urban areas = 2 of land bull Dense developed urban areas only 1 of land [2]
36
Potentials to Increase Urban Albdeo is 01
bull Typical urban area is 25 roof and 35 paved surfaces
bull Roof albedo can increase by 025 for a net change of 025x025=0063
bull Paved surfaces albedo can increase by 015 for a net change of 035x015=0052
bull Net urban area albedo change at least 010
37
Effect of Increasing Urban Albedo by 01
bull Net Change in Global albedo = [CityLand]x[LandGlobe]x∆a = [2]x[1]x∆a = 001 x 029 x01 = 00003 [3]
bull The effect on global temperature frac34 Using three different calculations is about 001K
38
Carbon Equivalency bull Modelers estimate a warming of 2K in 60 years so
003Kyear bull Change of 01 in urban albedo will result in 001K a delay
of ~03 years in global warming bull Worldrsquos current rate of CO2 emissions =
25 G tonsyear (41 tonsyear per person) bull Worldrsquos rate of CO2 emissions averaged over next 60
years = 40 G tonsyear bull Hence 03 years delay is worth 12 Gt CO2 ~ 200 Mt
CO2year
39
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
White Roofs Measured Cooling Savings
bull Sacramento 80 in a house 35 in two school bungalows
bull Florida 10-43 in several houses average 19
bull California and Florida 5ndash20 in several commercial buildings
8
Potential National Savings from Changing Roof Reflectivity
Peak Demand Savings in All US $37M
$35M
$16M
$27M $10M $20M $8M
$3M New York $9M $20M
Chicago
$9M
Philadelphia DCBaltimore
Los Angeles
Phoenix DallasFt Worth
Atlanta
Houston Miami New Orleans FtLauderdale
9
ldquoCoolrdquo products for low-sloped roofs
bull Many materials available frac34 coating (white) frac34 single-ply membrane (white) frac34 painted metal (white cool colored)
bull Products are rated by the Cool Roof Rating Council (CRRC) frac34 labels solar reflectance thermal emittance
10
frac34 website wwwcoolroofsorg
Cool Roofing Materials Availability High-Sloped Roofs
bull Limited but expanding material availability frac34 Tile (several maufacturers) frac34 Coatings (one manufacturer) frac34 Metal (many manufacturers) frac34 Shake (only for custom application) frac34 Shingles (one manufacturer)
bull Over 70 of high-sloped roofs use hot asphalt shingles
11
12
ISPLBNL Shingle With Whiter Roofing Granules
13
White is lsquocoolrsquo in Bermuda
14
and in Santorini Greece
15
Cool Roof Technologies
flat white
pitched white
pitched cool amp colored
Old New
16
Cool Colors Reflect Invisible Near-Infrared Sunlight
Cool and Standard Brown Metal Roofing Panels
bull Solar reflectance ~ 02 higher bull Afternoon surface temperature ~ 10ordmC lower
17
Courtesy BASF
Coatings
18
Example Dioxazine Purple Over Various Undercoats
bull Two-layer system frac34 top coat thin layer of dioxazine purple (14-27 microm) frac34 undercoat or substrate
aluminum foil (~ 25 microm) opaque white paint (~1000 microm) non-opaque white paint (~ 25 microm) opaque black paint (~ 25 microm)
purple over
aluminum foil
purple over
opaque white paint
purple over
non-opaque white paint
purple over
opaque black paint
19
Dioxazine Purple Reflectances
over aluminum Rsolar = 041
over opaque white Rsolar = 042
over non-opaque white Rsolar = 030
over opaque black Rsolar = 005
20
National Labs and Industrial Partnership bull Program is sponsored by
CECPIER bull ORNL and LBNL are teaming
with industry bull Broad industrial partnership
bull Industry partners frac34 3M (ganules) frac34 American Roof Tile Coating frac34 BASF (metal) frac34 Custom-Bilt Metals frac34 Elk Manufacturing (shingles) frac34 Ferro frac34 GAF (shingles) frac34 Hanson Roof Tile frac34 ISP Minerals (ganules) frac34 MCA (tiles) frac34 Monier Lifetile (tile) frac34 Shepherd Color Company
Cool and Standard Color-Matched Concrete Tiles
cool Courtesy American Rooftile Coatings
standard
bull Can increase solar reflectance by up to 05 bull Gain greatest for dark colors
∆R=037 ∆R=026 ∆R=023 ∆R=015 ∆R=029 ∆R=029
21
22
Increasing solar reflectance of fiberglass asphalt shingles prototypes
cooler ρ=028
ρ = solar reflectance
ρ=036
warmer ρ=023 ρ=027 ρ=028
ρ=037
23
Increasing solar reflectance of fiberglass asphalt shingles Elk Prestiquereg Cool Color Series
24
Increasing solar reflectance of metal roofing BASF Ultra-Coolreg metal roof coatings
numbers denote solar reflectances cooler (warmer)
Courtesy BASF
Industrial Coatings
25
Cool Metal Roofs
Increasing solar reflectance of clay tiles MCA Clay Tile cool colored tiles
26
Model Color Initial solar reflectance
Solar reflectance after 3 years
Weathered Green Blend
043 049
Natural Red 043 038
Brick Red 042 040
White Buff 068 056
Tobacco 043 041
27
Non-residential building energy and equipment savings15-year net present value of savings ($1000 ft2)
30-year net present value of savings ($1000 ft2) concrete tile roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 39 53 37 56 42 58 39 71 74 60 64 55 68 66 66 60
Energy 406 917 726 992 781 1593 1432 1822 1862 1390 1190 1109 1355 1477 1900 791 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
28
30-year net present value of savings ($1000 ft2) metal roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 41 57 41 61 47 57 48 83 88 65 71 60 73 72 71 65
Energy 495 1053 847 1128 919 1870 1692 2141 2181 1561 1330 1243 1507 1648 2093 918 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
29
Cool Roofs Standards bull Building standards for reflective roofs
- American Society of Heating and Air-conditioning Engineers (ASHRAE) New commercial and residential buildings
- Many state California Georgia Florida Hawaii hellip bull Air quality standards
- South Coast AQMD - SF Bay Area AQMD - EPArsquos SIP (State Implementation Plans)
30
White Roofs Programs in California
bull One Time CEC Incentive -- $20 Million frac34 at $015 to $020 per square foot
bull California utilities incentives bull 2001 to 2005-- credits white and cool colored
roofs bull 2005 requires cool flat roofs bull 2008 may require cool roofs for all buildings
31
Cool Roof Programs around the World
32
bull US bull Europe bull Asia bull Middle East
bull China bull India (Hyderabad
demos see graphs funded by USAID)
Cool Roofs to Save CO2
33
Cool Surfaces also Cool the Globe
bull Cool roof standards are designed to reduce ac demand save money and save emissions In Los Angeles they will eventually save ~$100000 per hour
bull Annual savings in the US = $1-2B ~ 7 M tons CO2
bull Annual savings in the world = $10-15B ~ 100 M tons CO2
bull But higher albedo surfaces (roofs and pavements) directly cool the world (001 K) quite independent of avoided CO2 So we discuss the effect of cool surfaces for tropical temperate cities
34
35
100 Largest Cities have 670 M People
0
1000
2000
3000
4000
5000
0 10 20 30 40
Population (M)
Are
a D
ensi
ty(m
2 per
son)
Mean = 560 m2p Med = 430 m2p
Tokyo
Mexico City New York City Mumbai Satildeo Paulo
Dense Urban Areas are 1 of Land
bull Area of the Earth = 511x1012 m2
bull Land Area (29) = 148x1012 m2 [1] bull Area of the 100 largest cities = 038x1012 m2 = 026
of Land Area for 670 M people bull Assuming 3B live in urban area urban areas =
[3000670] x 026 = 12 of land bull But smaller cities have lower population density
hence urban areas = 2 of land bull Dense developed urban areas only 1 of land [2]
36
Potentials to Increase Urban Albdeo is 01
bull Typical urban area is 25 roof and 35 paved surfaces
bull Roof albedo can increase by 025 for a net change of 025x025=0063
bull Paved surfaces albedo can increase by 015 for a net change of 035x015=0052
bull Net urban area albedo change at least 010
37
Effect of Increasing Urban Albedo by 01
bull Net Change in Global albedo = [CityLand]x[LandGlobe]x∆a = [2]x[1]x∆a = 001 x 029 x01 = 00003 [3]
bull The effect on global temperature frac34 Using three different calculations is about 001K
38
Carbon Equivalency bull Modelers estimate a warming of 2K in 60 years so
003Kyear bull Change of 01 in urban albedo will result in 001K a delay
of ~03 years in global warming bull Worldrsquos current rate of CO2 emissions =
25 G tonsyear (41 tonsyear per person) bull Worldrsquos rate of CO2 emissions averaged over next 60
years = 40 G tonsyear bull Hence 03 years delay is worth 12 Gt CO2 ~ 200 Mt
CO2year
39
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
Potential National Savings from Changing Roof Reflectivity
Peak Demand Savings in All US $37M
$35M
$16M
$27M $10M $20M $8M
$3M New York $9M $20M
Chicago
$9M
Philadelphia DCBaltimore
Los Angeles
Phoenix DallasFt Worth
Atlanta
Houston Miami New Orleans FtLauderdale
9
ldquoCoolrdquo products for low-sloped roofs
bull Many materials available frac34 coating (white) frac34 single-ply membrane (white) frac34 painted metal (white cool colored)
bull Products are rated by the Cool Roof Rating Council (CRRC) frac34 labels solar reflectance thermal emittance
10
frac34 website wwwcoolroofsorg
Cool Roofing Materials Availability High-Sloped Roofs
bull Limited but expanding material availability frac34 Tile (several maufacturers) frac34 Coatings (one manufacturer) frac34 Metal (many manufacturers) frac34 Shake (only for custom application) frac34 Shingles (one manufacturer)
bull Over 70 of high-sloped roofs use hot asphalt shingles
11
12
ISPLBNL Shingle With Whiter Roofing Granules
13
White is lsquocoolrsquo in Bermuda
14
and in Santorini Greece
15
Cool Roof Technologies
flat white
pitched white
pitched cool amp colored
Old New
16
Cool Colors Reflect Invisible Near-Infrared Sunlight
Cool and Standard Brown Metal Roofing Panels
bull Solar reflectance ~ 02 higher bull Afternoon surface temperature ~ 10ordmC lower
17
Courtesy BASF
Coatings
18
Example Dioxazine Purple Over Various Undercoats
bull Two-layer system frac34 top coat thin layer of dioxazine purple (14-27 microm) frac34 undercoat or substrate
aluminum foil (~ 25 microm) opaque white paint (~1000 microm) non-opaque white paint (~ 25 microm) opaque black paint (~ 25 microm)
purple over
aluminum foil
purple over
opaque white paint
purple over
non-opaque white paint
purple over
opaque black paint
19
Dioxazine Purple Reflectances
over aluminum Rsolar = 041
over opaque white Rsolar = 042
over non-opaque white Rsolar = 030
over opaque black Rsolar = 005
20
National Labs and Industrial Partnership bull Program is sponsored by
CECPIER bull ORNL and LBNL are teaming
with industry bull Broad industrial partnership
bull Industry partners frac34 3M (ganules) frac34 American Roof Tile Coating frac34 BASF (metal) frac34 Custom-Bilt Metals frac34 Elk Manufacturing (shingles) frac34 Ferro frac34 GAF (shingles) frac34 Hanson Roof Tile frac34 ISP Minerals (ganules) frac34 MCA (tiles) frac34 Monier Lifetile (tile) frac34 Shepherd Color Company
Cool and Standard Color-Matched Concrete Tiles
cool Courtesy American Rooftile Coatings
standard
bull Can increase solar reflectance by up to 05 bull Gain greatest for dark colors
∆R=037 ∆R=026 ∆R=023 ∆R=015 ∆R=029 ∆R=029
21
22
Increasing solar reflectance of fiberglass asphalt shingles prototypes
cooler ρ=028
ρ = solar reflectance
ρ=036
warmer ρ=023 ρ=027 ρ=028
ρ=037
23
Increasing solar reflectance of fiberglass asphalt shingles Elk Prestiquereg Cool Color Series
24
Increasing solar reflectance of metal roofing BASF Ultra-Coolreg metal roof coatings
numbers denote solar reflectances cooler (warmer)
Courtesy BASF
Industrial Coatings
25
Cool Metal Roofs
Increasing solar reflectance of clay tiles MCA Clay Tile cool colored tiles
26
Model Color Initial solar reflectance
Solar reflectance after 3 years
Weathered Green Blend
043 049
Natural Red 043 038
Brick Red 042 040
White Buff 068 056
Tobacco 043 041
27
Non-residential building energy and equipment savings15-year net present value of savings ($1000 ft2)
30-year net present value of savings ($1000 ft2) concrete tile roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 39 53 37 56 42 58 39 71 74 60 64 55 68 66 66 60
Energy 406 917 726 992 781 1593 1432 1822 1862 1390 1190 1109 1355 1477 1900 791 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
28
30-year net present value of savings ($1000 ft2) metal roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 41 57 41 61 47 57 48 83 88 65 71 60 73 72 71 65
Energy 495 1053 847 1128 919 1870 1692 2141 2181 1561 1330 1243 1507 1648 2093 918 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
29
Cool Roofs Standards bull Building standards for reflective roofs
- American Society of Heating and Air-conditioning Engineers (ASHRAE) New commercial and residential buildings
- Many state California Georgia Florida Hawaii hellip bull Air quality standards
- South Coast AQMD - SF Bay Area AQMD - EPArsquos SIP (State Implementation Plans)
30
White Roofs Programs in California
bull One Time CEC Incentive -- $20 Million frac34 at $015 to $020 per square foot
bull California utilities incentives bull 2001 to 2005-- credits white and cool colored
roofs bull 2005 requires cool flat roofs bull 2008 may require cool roofs for all buildings
31
Cool Roof Programs around the World
32
bull US bull Europe bull Asia bull Middle East
bull China bull India (Hyderabad
demos see graphs funded by USAID)
Cool Roofs to Save CO2
33
Cool Surfaces also Cool the Globe
bull Cool roof standards are designed to reduce ac demand save money and save emissions In Los Angeles they will eventually save ~$100000 per hour
bull Annual savings in the US = $1-2B ~ 7 M tons CO2
bull Annual savings in the world = $10-15B ~ 100 M tons CO2
bull But higher albedo surfaces (roofs and pavements) directly cool the world (001 K) quite independent of avoided CO2 So we discuss the effect of cool surfaces for tropical temperate cities
34
35
100 Largest Cities have 670 M People
0
1000
2000
3000
4000
5000
0 10 20 30 40
Population (M)
Are
a D
ensi
ty(m
2 per
son)
Mean = 560 m2p Med = 430 m2p
Tokyo
Mexico City New York City Mumbai Satildeo Paulo
Dense Urban Areas are 1 of Land
bull Area of the Earth = 511x1012 m2
bull Land Area (29) = 148x1012 m2 [1] bull Area of the 100 largest cities = 038x1012 m2 = 026
of Land Area for 670 M people bull Assuming 3B live in urban area urban areas =
[3000670] x 026 = 12 of land bull But smaller cities have lower population density
hence urban areas = 2 of land bull Dense developed urban areas only 1 of land [2]
36
Potentials to Increase Urban Albdeo is 01
bull Typical urban area is 25 roof and 35 paved surfaces
bull Roof albedo can increase by 025 for a net change of 025x025=0063
bull Paved surfaces albedo can increase by 015 for a net change of 035x015=0052
bull Net urban area albedo change at least 010
37
Effect of Increasing Urban Albedo by 01
bull Net Change in Global albedo = [CityLand]x[LandGlobe]x∆a = [2]x[1]x∆a = 001 x 029 x01 = 00003 [3]
bull The effect on global temperature frac34 Using three different calculations is about 001K
38
Carbon Equivalency bull Modelers estimate a warming of 2K in 60 years so
003Kyear bull Change of 01 in urban albedo will result in 001K a delay
of ~03 years in global warming bull Worldrsquos current rate of CO2 emissions =
25 G tonsyear (41 tonsyear per person) bull Worldrsquos rate of CO2 emissions averaged over next 60
years = 40 G tonsyear bull Hence 03 years delay is worth 12 Gt CO2 ~ 200 Mt
CO2year
39
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
ldquoCoolrdquo products for low-sloped roofs
bull Many materials available frac34 coating (white) frac34 single-ply membrane (white) frac34 painted metal (white cool colored)
bull Products are rated by the Cool Roof Rating Council (CRRC) frac34 labels solar reflectance thermal emittance
10
frac34 website wwwcoolroofsorg
Cool Roofing Materials Availability High-Sloped Roofs
bull Limited but expanding material availability frac34 Tile (several maufacturers) frac34 Coatings (one manufacturer) frac34 Metal (many manufacturers) frac34 Shake (only for custom application) frac34 Shingles (one manufacturer)
bull Over 70 of high-sloped roofs use hot asphalt shingles
11
12
ISPLBNL Shingle With Whiter Roofing Granules
13
White is lsquocoolrsquo in Bermuda
14
and in Santorini Greece
15
Cool Roof Technologies
flat white
pitched white
pitched cool amp colored
Old New
16
Cool Colors Reflect Invisible Near-Infrared Sunlight
Cool and Standard Brown Metal Roofing Panels
bull Solar reflectance ~ 02 higher bull Afternoon surface temperature ~ 10ordmC lower
17
Courtesy BASF
Coatings
18
Example Dioxazine Purple Over Various Undercoats
bull Two-layer system frac34 top coat thin layer of dioxazine purple (14-27 microm) frac34 undercoat or substrate
aluminum foil (~ 25 microm) opaque white paint (~1000 microm) non-opaque white paint (~ 25 microm) opaque black paint (~ 25 microm)
purple over
aluminum foil
purple over
opaque white paint
purple over
non-opaque white paint
purple over
opaque black paint
19
Dioxazine Purple Reflectances
over aluminum Rsolar = 041
over opaque white Rsolar = 042
over non-opaque white Rsolar = 030
over opaque black Rsolar = 005
20
National Labs and Industrial Partnership bull Program is sponsored by
CECPIER bull ORNL and LBNL are teaming
with industry bull Broad industrial partnership
bull Industry partners frac34 3M (ganules) frac34 American Roof Tile Coating frac34 BASF (metal) frac34 Custom-Bilt Metals frac34 Elk Manufacturing (shingles) frac34 Ferro frac34 GAF (shingles) frac34 Hanson Roof Tile frac34 ISP Minerals (ganules) frac34 MCA (tiles) frac34 Monier Lifetile (tile) frac34 Shepherd Color Company
Cool and Standard Color-Matched Concrete Tiles
cool Courtesy American Rooftile Coatings
standard
bull Can increase solar reflectance by up to 05 bull Gain greatest for dark colors
∆R=037 ∆R=026 ∆R=023 ∆R=015 ∆R=029 ∆R=029
21
22
Increasing solar reflectance of fiberglass asphalt shingles prototypes
cooler ρ=028
ρ = solar reflectance
ρ=036
warmer ρ=023 ρ=027 ρ=028
ρ=037
23
Increasing solar reflectance of fiberglass asphalt shingles Elk Prestiquereg Cool Color Series
24
Increasing solar reflectance of metal roofing BASF Ultra-Coolreg metal roof coatings
numbers denote solar reflectances cooler (warmer)
Courtesy BASF
Industrial Coatings
25
Cool Metal Roofs
Increasing solar reflectance of clay tiles MCA Clay Tile cool colored tiles
26
Model Color Initial solar reflectance
Solar reflectance after 3 years
Weathered Green Blend
043 049
Natural Red 043 038
Brick Red 042 040
White Buff 068 056
Tobacco 043 041
27
Non-residential building energy and equipment savings15-year net present value of savings ($1000 ft2)
30-year net present value of savings ($1000 ft2) concrete tile roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 39 53 37 56 42 58 39 71 74 60 64 55 68 66 66 60
Energy 406 917 726 992 781 1593 1432 1822 1862 1390 1190 1109 1355 1477 1900 791 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
28
30-year net present value of savings ($1000 ft2) metal roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 41 57 41 61 47 57 48 83 88 65 71 60 73 72 71 65
Energy 495 1053 847 1128 919 1870 1692 2141 2181 1561 1330 1243 1507 1648 2093 918 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
29
Cool Roofs Standards bull Building standards for reflective roofs
- American Society of Heating and Air-conditioning Engineers (ASHRAE) New commercial and residential buildings
- Many state California Georgia Florida Hawaii hellip bull Air quality standards
- South Coast AQMD - SF Bay Area AQMD - EPArsquos SIP (State Implementation Plans)
30
White Roofs Programs in California
bull One Time CEC Incentive -- $20 Million frac34 at $015 to $020 per square foot
bull California utilities incentives bull 2001 to 2005-- credits white and cool colored
roofs bull 2005 requires cool flat roofs bull 2008 may require cool roofs for all buildings
31
Cool Roof Programs around the World
32
bull US bull Europe bull Asia bull Middle East
bull China bull India (Hyderabad
demos see graphs funded by USAID)
Cool Roofs to Save CO2
33
Cool Surfaces also Cool the Globe
bull Cool roof standards are designed to reduce ac demand save money and save emissions In Los Angeles they will eventually save ~$100000 per hour
bull Annual savings in the US = $1-2B ~ 7 M tons CO2
bull Annual savings in the world = $10-15B ~ 100 M tons CO2
bull But higher albedo surfaces (roofs and pavements) directly cool the world (001 K) quite independent of avoided CO2 So we discuss the effect of cool surfaces for tropical temperate cities
34
35
100 Largest Cities have 670 M People
0
1000
2000
3000
4000
5000
0 10 20 30 40
Population (M)
Are
a D
ensi
ty(m
2 per
son)
Mean = 560 m2p Med = 430 m2p
Tokyo
Mexico City New York City Mumbai Satildeo Paulo
Dense Urban Areas are 1 of Land
bull Area of the Earth = 511x1012 m2
bull Land Area (29) = 148x1012 m2 [1] bull Area of the 100 largest cities = 038x1012 m2 = 026
of Land Area for 670 M people bull Assuming 3B live in urban area urban areas =
[3000670] x 026 = 12 of land bull But smaller cities have lower population density
hence urban areas = 2 of land bull Dense developed urban areas only 1 of land [2]
36
Potentials to Increase Urban Albdeo is 01
bull Typical urban area is 25 roof and 35 paved surfaces
bull Roof albedo can increase by 025 for a net change of 025x025=0063
bull Paved surfaces albedo can increase by 015 for a net change of 035x015=0052
bull Net urban area albedo change at least 010
37
Effect of Increasing Urban Albedo by 01
bull Net Change in Global albedo = [CityLand]x[LandGlobe]x∆a = [2]x[1]x∆a = 001 x 029 x01 = 00003 [3]
bull The effect on global temperature frac34 Using three different calculations is about 001K
38
Carbon Equivalency bull Modelers estimate a warming of 2K in 60 years so
003Kyear bull Change of 01 in urban albedo will result in 001K a delay
of ~03 years in global warming bull Worldrsquos current rate of CO2 emissions =
25 G tonsyear (41 tonsyear per person) bull Worldrsquos rate of CO2 emissions averaged over next 60
years = 40 G tonsyear bull Hence 03 years delay is worth 12 Gt CO2 ~ 200 Mt
CO2year
39
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
Cool Roofing Materials Availability High-Sloped Roofs
bull Limited but expanding material availability frac34 Tile (several maufacturers) frac34 Coatings (one manufacturer) frac34 Metal (many manufacturers) frac34 Shake (only for custom application) frac34 Shingles (one manufacturer)
bull Over 70 of high-sloped roofs use hot asphalt shingles
11
12
ISPLBNL Shingle With Whiter Roofing Granules
13
White is lsquocoolrsquo in Bermuda
14
and in Santorini Greece
15
Cool Roof Technologies
flat white
pitched white
pitched cool amp colored
Old New
16
Cool Colors Reflect Invisible Near-Infrared Sunlight
Cool and Standard Brown Metal Roofing Panels
bull Solar reflectance ~ 02 higher bull Afternoon surface temperature ~ 10ordmC lower
17
Courtesy BASF
Coatings
18
Example Dioxazine Purple Over Various Undercoats
bull Two-layer system frac34 top coat thin layer of dioxazine purple (14-27 microm) frac34 undercoat or substrate
aluminum foil (~ 25 microm) opaque white paint (~1000 microm) non-opaque white paint (~ 25 microm) opaque black paint (~ 25 microm)
purple over
aluminum foil
purple over
opaque white paint
purple over
non-opaque white paint
purple over
opaque black paint
19
Dioxazine Purple Reflectances
over aluminum Rsolar = 041
over opaque white Rsolar = 042
over non-opaque white Rsolar = 030
over opaque black Rsolar = 005
20
National Labs and Industrial Partnership bull Program is sponsored by
CECPIER bull ORNL and LBNL are teaming
with industry bull Broad industrial partnership
bull Industry partners frac34 3M (ganules) frac34 American Roof Tile Coating frac34 BASF (metal) frac34 Custom-Bilt Metals frac34 Elk Manufacturing (shingles) frac34 Ferro frac34 GAF (shingles) frac34 Hanson Roof Tile frac34 ISP Minerals (ganules) frac34 MCA (tiles) frac34 Monier Lifetile (tile) frac34 Shepherd Color Company
Cool and Standard Color-Matched Concrete Tiles
cool Courtesy American Rooftile Coatings
standard
bull Can increase solar reflectance by up to 05 bull Gain greatest for dark colors
∆R=037 ∆R=026 ∆R=023 ∆R=015 ∆R=029 ∆R=029
21
22
Increasing solar reflectance of fiberglass asphalt shingles prototypes
cooler ρ=028
ρ = solar reflectance
ρ=036
warmer ρ=023 ρ=027 ρ=028
ρ=037
23
Increasing solar reflectance of fiberglass asphalt shingles Elk Prestiquereg Cool Color Series
24
Increasing solar reflectance of metal roofing BASF Ultra-Coolreg metal roof coatings
numbers denote solar reflectances cooler (warmer)
Courtesy BASF
Industrial Coatings
25
Cool Metal Roofs
Increasing solar reflectance of clay tiles MCA Clay Tile cool colored tiles
26
Model Color Initial solar reflectance
Solar reflectance after 3 years
Weathered Green Blend
043 049
Natural Red 043 038
Brick Red 042 040
White Buff 068 056
Tobacco 043 041
27
Non-residential building energy and equipment savings15-year net present value of savings ($1000 ft2)
30-year net present value of savings ($1000 ft2) concrete tile roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 39 53 37 56 42 58 39 71 74 60 64 55 68 66 66 60
Energy 406 917 726 992 781 1593 1432 1822 1862 1390 1190 1109 1355 1477 1900 791 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
28
30-year net present value of savings ($1000 ft2) metal roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 41 57 41 61 47 57 48 83 88 65 71 60 73 72 71 65
Energy 495 1053 847 1128 919 1870 1692 2141 2181 1561 1330 1243 1507 1648 2093 918 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
29
Cool Roofs Standards bull Building standards for reflective roofs
- American Society of Heating and Air-conditioning Engineers (ASHRAE) New commercial and residential buildings
- Many state California Georgia Florida Hawaii hellip bull Air quality standards
- South Coast AQMD - SF Bay Area AQMD - EPArsquos SIP (State Implementation Plans)
30
White Roofs Programs in California
bull One Time CEC Incentive -- $20 Million frac34 at $015 to $020 per square foot
bull California utilities incentives bull 2001 to 2005-- credits white and cool colored
roofs bull 2005 requires cool flat roofs bull 2008 may require cool roofs for all buildings
31
Cool Roof Programs around the World
32
bull US bull Europe bull Asia bull Middle East
bull China bull India (Hyderabad
demos see graphs funded by USAID)
Cool Roofs to Save CO2
33
Cool Surfaces also Cool the Globe
bull Cool roof standards are designed to reduce ac demand save money and save emissions In Los Angeles they will eventually save ~$100000 per hour
bull Annual savings in the US = $1-2B ~ 7 M tons CO2
bull Annual savings in the world = $10-15B ~ 100 M tons CO2
bull But higher albedo surfaces (roofs and pavements) directly cool the world (001 K) quite independent of avoided CO2 So we discuss the effect of cool surfaces for tropical temperate cities
34
35
100 Largest Cities have 670 M People
0
1000
2000
3000
4000
5000
0 10 20 30 40
Population (M)
Are
a D
ensi
ty(m
2 per
son)
Mean = 560 m2p Med = 430 m2p
Tokyo
Mexico City New York City Mumbai Satildeo Paulo
Dense Urban Areas are 1 of Land
bull Area of the Earth = 511x1012 m2
bull Land Area (29) = 148x1012 m2 [1] bull Area of the 100 largest cities = 038x1012 m2 = 026
of Land Area for 670 M people bull Assuming 3B live in urban area urban areas =
[3000670] x 026 = 12 of land bull But smaller cities have lower population density
hence urban areas = 2 of land bull Dense developed urban areas only 1 of land [2]
36
Potentials to Increase Urban Albdeo is 01
bull Typical urban area is 25 roof and 35 paved surfaces
bull Roof albedo can increase by 025 for a net change of 025x025=0063
bull Paved surfaces albedo can increase by 015 for a net change of 035x015=0052
bull Net urban area albedo change at least 010
37
Effect of Increasing Urban Albedo by 01
bull Net Change in Global albedo = [CityLand]x[LandGlobe]x∆a = [2]x[1]x∆a = 001 x 029 x01 = 00003 [3]
bull The effect on global temperature frac34 Using three different calculations is about 001K
38
Carbon Equivalency bull Modelers estimate a warming of 2K in 60 years so
003Kyear bull Change of 01 in urban albedo will result in 001K a delay
of ~03 years in global warming bull Worldrsquos current rate of CO2 emissions =
25 G tonsyear (41 tonsyear per person) bull Worldrsquos rate of CO2 emissions averaged over next 60
years = 40 G tonsyear bull Hence 03 years delay is worth 12 Gt CO2 ~ 200 Mt
CO2year
39
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
12
ISPLBNL Shingle With Whiter Roofing Granules
13
White is lsquocoolrsquo in Bermuda
14
and in Santorini Greece
15
Cool Roof Technologies
flat white
pitched white
pitched cool amp colored
Old New
16
Cool Colors Reflect Invisible Near-Infrared Sunlight
Cool and Standard Brown Metal Roofing Panels
bull Solar reflectance ~ 02 higher bull Afternoon surface temperature ~ 10ordmC lower
17
Courtesy BASF
Coatings
18
Example Dioxazine Purple Over Various Undercoats
bull Two-layer system frac34 top coat thin layer of dioxazine purple (14-27 microm) frac34 undercoat or substrate
aluminum foil (~ 25 microm) opaque white paint (~1000 microm) non-opaque white paint (~ 25 microm) opaque black paint (~ 25 microm)
purple over
aluminum foil
purple over
opaque white paint
purple over
non-opaque white paint
purple over
opaque black paint
19
Dioxazine Purple Reflectances
over aluminum Rsolar = 041
over opaque white Rsolar = 042
over non-opaque white Rsolar = 030
over opaque black Rsolar = 005
20
National Labs and Industrial Partnership bull Program is sponsored by
CECPIER bull ORNL and LBNL are teaming
with industry bull Broad industrial partnership
bull Industry partners frac34 3M (ganules) frac34 American Roof Tile Coating frac34 BASF (metal) frac34 Custom-Bilt Metals frac34 Elk Manufacturing (shingles) frac34 Ferro frac34 GAF (shingles) frac34 Hanson Roof Tile frac34 ISP Minerals (ganules) frac34 MCA (tiles) frac34 Monier Lifetile (tile) frac34 Shepherd Color Company
Cool and Standard Color-Matched Concrete Tiles
cool Courtesy American Rooftile Coatings
standard
bull Can increase solar reflectance by up to 05 bull Gain greatest for dark colors
∆R=037 ∆R=026 ∆R=023 ∆R=015 ∆R=029 ∆R=029
21
22
Increasing solar reflectance of fiberglass asphalt shingles prototypes
cooler ρ=028
ρ = solar reflectance
ρ=036
warmer ρ=023 ρ=027 ρ=028
ρ=037
23
Increasing solar reflectance of fiberglass asphalt shingles Elk Prestiquereg Cool Color Series
24
Increasing solar reflectance of metal roofing BASF Ultra-Coolreg metal roof coatings
numbers denote solar reflectances cooler (warmer)
Courtesy BASF
Industrial Coatings
25
Cool Metal Roofs
Increasing solar reflectance of clay tiles MCA Clay Tile cool colored tiles
26
Model Color Initial solar reflectance
Solar reflectance after 3 years
Weathered Green Blend
043 049
Natural Red 043 038
Brick Red 042 040
White Buff 068 056
Tobacco 043 041
27
Non-residential building energy and equipment savings15-year net present value of savings ($1000 ft2)
30-year net present value of savings ($1000 ft2) concrete tile roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 39 53 37 56 42 58 39 71 74 60 64 55 68 66 66 60
Energy 406 917 726 992 781 1593 1432 1822 1862 1390 1190 1109 1355 1477 1900 791 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
28
30-year net present value of savings ($1000 ft2) metal roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 41 57 41 61 47 57 48 83 88 65 71 60 73 72 71 65
Energy 495 1053 847 1128 919 1870 1692 2141 2181 1561 1330 1243 1507 1648 2093 918 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
29
Cool Roofs Standards bull Building standards for reflective roofs
- American Society of Heating and Air-conditioning Engineers (ASHRAE) New commercial and residential buildings
- Many state California Georgia Florida Hawaii hellip bull Air quality standards
- South Coast AQMD - SF Bay Area AQMD - EPArsquos SIP (State Implementation Plans)
30
White Roofs Programs in California
bull One Time CEC Incentive -- $20 Million frac34 at $015 to $020 per square foot
bull California utilities incentives bull 2001 to 2005-- credits white and cool colored
roofs bull 2005 requires cool flat roofs bull 2008 may require cool roofs for all buildings
31
Cool Roof Programs around the World
32
bull US bull Europe bull Asia bull Middle East
bull China bull India (Hyderabad
demos see graphs funded by USAID)
Cool Roofs to Save CO2
33
Cool Surfaces also Cool the Globe
bull Cool roof standards are designed to reduce ac demand save money and save emissions In Los Angeles they will eventually save ~$100000 per hour
bull Annual savings in the US = $1-2B ~ 7 M tons CO2
bull Annual savings in the world = $10-15B ~ 100 M tons CO2
bull But higher albedo surfaces (roofs and pavements) directly cool the world (001 K) quite independent of avoided CO2 So we discuss the effect of cool surfaces for tropical temperate cities
34
35
100 Largest Cities have 670 M People
0
1000
2000
3000
4000
5000
0 10 20 30 40
Population (M)
Are
a D
ensi
ty(m
2 per
son)
Mean = 560 m2p Med = 430 m2p
Tokyo
Mexico City New York City Mumbai Satildeo Paulo
Dense Urban Areas are 1 of Land
bull Area of the Earth = 511x1012 m2
bull Land Area (29) = 148x1012 m2 [1] bull Area of the 100 largest cities = 038x1012 m2 = 026
of Land Area for 670 M people bull Assuming 3B live in urban area urban areas =
[3000670] x 026 = 12 of land bull But smaller cities have lower population density
hence urban areas = 2 of land bull Dense developed urban areas only 1 of land [2]
36
Potentials to Increase Urban Albdeo is 01
bull Typical urban area is 25 roof and 35 paved surfaces
bull Roof albedo can increase by 025 for a net change of 025x025=0063
bull Paved surfaces albedo can increase by 015 for a net change of 035x015=0052
bull Net urban area albedo change at least 010
37
Effect of Increasing Urban Albedo by 01
bull Net Change in Global albedo = [CityLand]x[LandGlobe]x∆a = [2]x[1]x∆a = 001 x 029 x01 = 00003 [3]
bull The effect on global temperature frac34 Using three different calculations is about 001K
38
Carbon Equivalency bull Modelers estimate a warming of 2K in 60 years so
003Kyear bull Change of 01 in urban albedo will result in 001K a delay
of ~03 years in global warming bull Worldrsquos current rate of CO2 emissions =
25 G tonsyear (41 tonsyear per person) bull Worldrsquos rate of CO2 emissions averaged over next 60
years = 40 G tonsyear bull Hence 03 years delay is worth 12 Gt CO2 ~ 200 Mt
CO2year
39
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
13
White is lsquocoolrsquo in Bermuda
14
and in Santorini Greece
15
Cool Roof Technologies
flat white
pitched white
pitched cool amp colored
Old New
16
Cool Colors Reflect Invisible Near-Infrared Sunlight
Cool and Standard Brown Metal Roofing Panels
bull Solar reflectance ~ 02 higher bull Afternoon surface temperature ~ 10ordmC lower
17
Courtesy BASF
Coatings
18
Example Dioxazine Purple Over Various Undercoats
bull Two-layer system frac34 top coat thin layer of dioxazine purple (14-27 microm) frac34 undercoat or substrate
aluminum foil (~ 25 microm) opaque white paint (~1000 microm) non-opaque white paint (~ 25 microm) opaque black paint (~ 25 microm)
purple over
aluminum foil
purple over
opaque white paint
purple over
non-opaque white paint
purple over
opaque black paint
19
Dioxazine Purple Reflectances
over aluminum Rsolar = 041
over opaque white Rsolar = 042
over non-opaque white Rsolar = 030
over opaque black Rsolar = 005
20
National Labs and Industrial Partnership bull Program is sponsored by
CECPIER bull ORNL and LBNL are teaming
with industry bull Broad industrial partnership
bull Industry partners frac34 3M (ganules) frac34 American Roof Tile Coating frac34 BASF (metal) frac34 Custom-Bilt Metals frac34 Elk Manufacturing (shingles) frac34 Ferro frac34 GAF (shingles) frac34 Hanson Roof Tile frac34 ISP Minerals (ganules) frac34 MCA (tiles) frac34 Monier Lifetile (tile) frac34 Shepherd Color Company
Cool and Standard Color-Matched Concrete Tiles
cool Courtesy American Rooftile Coatings
standard
bull Can increase solar reflectance by up to 05 bull Gain greatest for dark colors
∆R=037 ∆R=026 ∆R=023 ∆R=015 ∆R=029 ∆R=029
21
22
Increasing solar reflectance of fiberglass asphalt shingles prototypes
cooler ρ=028
ρ = solar reflectance
ρ=036
warmer ρ=023 ρ=027 ρ=028
ρ=037
23
Increasing solar reflectance of fiberglass asphalt shingles Elk Prestiquereg Cool Color Series
24
Increasing solar reflectance of metal roofing BASF Ultra-Coolreg metal roof coatings
numbers denote solar reflectances cooler (warmer)
Courtesy BASF
Industrial Coatings
25
Cool Metal Roofs
Increasing solar reflectance of clay tiles MCA Clay Tile cool colored tiles
26
Model Color Initial solar reflectance
Solar reflectance after 3 years
Weathered Green Blend
043 049
Natural Red 043 038
Brick Red 042 040
White Buff 068 056
Tobacco 043 041
27
Non-residential building energy and equipment savings15-year net present value of savings ($1000 ft2)
30-year net present value of savings ($1000 ft2) concrete tile roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 39 53 37 56 42 58 39 71 74 60 64 55 68 66 66 60
Energy 406 917 726 992 781 1593 1432 1822 1862 1390 1190 1109 1355 1477 1900 791 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
28
30-year net present value of savings ($1000 ft2) metal roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 41 57 41 61 47 57 48 83 88 65 71 60 73 72 71 65
Energy 495 1053 847 1128 919 1870 1692 2141 2181 1561 1330 1243 1507 1648 2093 918 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
29
Cool Roofs Standards bull Building standards for reflective roofs
- American Society of Heating and Air-conditioning Engineers (ASHRAE) New commercial and residential buildings
- Many state California Georgia Florida Hawaii hellip bull Air quality standards
- South Coast AQMD - SF Bay Area AQMD - EPArsquos SIP (State Implementation Plans)
30
White Roofs Programs in California
bull One Time CEC Incentive -- $20 Million frac34 at $015 to $020 per square foot
bull California utilities incentives bull 2001 to 2005-- credits white and cool colored
roofs bull 2005 requires cool flat roofs bull 2008 may require cool roofs for all buildings
31
Cool Roof Programs around the World
32
bull US bull Europe bull Asia bull Middle East
bull China bull India (Hyderabad
demos see graphs funded by USAID)
Cool Roofs to Save CO2
33
Cool Surfaces also Cool the Globe
bull Cool roof standards are designed to reduce ac demand save money and save emissions In Los Angeles they will eventually save ~$100000 per hour
bull Annual savings in the US = $1-2B ~ 7 M tons CO2
bull Annual savings in the world = $10-15B ~ 100 M tons CO2
bull But higher albedo surfaces (roofs and pavements) directly cool the world (001 K) quite independent of avoided CO2 So we discuss the effect of cool surfaces for tropical temperate cities
34
35
100 Largest Cities have 670 M People
0
1000
2000
3000
4000
5000
0 10 20 30 40
Population (M)
Are
a D
ensi
ty(m
2 per
son)
Mean = 560 m2p Med = 430 m2p
Tokyo
Mexico City New York City Mumbai Satildeo Paulo
Dense Urban Areas are 1 of Land
bull Area of the Earth = 511x1012 m2
bull Land Area (29) = 148x1012 m2 [1] bull Area of the 100 largest cities = 038x1012 m2 = 026
of Land Area for 670 M people bull Assuming 3B live in urban area urban areas =
[3000670] x 026 = 12 of land bull But smaller cities have lower population density
hence urban areas = 2 of land bull Dense developed urban areas only 1 of land [2]
36
Potentials to Increase Urban Albdeo is 01
bull Typical urban area is 25 roof and 35 paved surfaces
bull Roof albedo can increase by 025 for a net change of 025x025=0063
bull Paved surfaces albedo can increase by 015 for a net change of 035x015=0052
bull Net urban area albedo change at least 010
37
Effect of Increasing Urban Albedo by 01
bull Net Change in Global albedo = [CityLand]x[LandGlobe]x∆a = [2]x[1]x∆a = 001 x 029 x01 = 00003 [3]
bull The effect on global temperature frac34 Using three different calculations is about 001K
38
Carbon Equivalency bull Modelers estimate a warming of 2K in 60 years so
003Kyear bull Change of 01 in urban albedo will result in 001K a delay
of ~03 years in global warming bull Worldrsquos current rate of CO2 emissions =
25 G tonsyear (41 tonsyear per person) bull Worldrsquos rate of CO2 emissions averaged over next 60
years = 40 G tonsyear bull Hence 03 years delay is worth 12 Gt CO2 ~ 200 Mt
CO2year
39
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
14
and in Santorini Greece
15
Cool Roof Technologies
flat white
pitched white
pitched cool amp colored
Old New
16
Cool Colors Reflect Invisible Near-Infrared Sunlight
Cool and Standard Brown Metal Roofing Panels
bull Solar reflectance ~ 02 higher bull Afternoon surface temperature ~ 10ordmC lower
17
Courtesy BASF
Coatings
18
Example Dioxazine Purple Over Various Undercoats
bull Two-layer system frac34 top coat thin layer of dioxazine purple (14-27 microm) frac34 undercoat or substrate
aluminum foil (~ 25 microm) opaque white paint (~1000 microm) non-opaque white paint (~ 25 microm) opaque black paint (~ 25 microm)
purple over
aluminum foil
purple over
opaque white paint
purple over
non-opaque white paint
purple over
opaque black paint
19
Dioxazine Purple Reflectances
over aluminum Rsolar = 041
over opaque white Rsolar = 042
over non-opaque white Rsolar = 030
over opaque black Rsolar = 005
20
National Labs and Industrial Partnership bull Program is sponsored by
CECPIER bull ORNL and LBNL are teaming
with industry bull Broad industrial partnership
bull Industry partners frac34 3M (ganules) frac34 American Roof Tile Coating frac34 BASF (metal) frac34 Custom-Bilt Metals frac34 Elk Manufacturing (shingles) frac34 Ferro frac34 GAF (shingles) frac34 Hanson Roof Tile frac34 ISP Minerals (ganules) frac34 MCA (tiles) frac34 Monier Lifetile (tile) frac34 Shepherd Color Company
Cool and Standard Color-Matched Concrete Tiles
cool Courtesy American Rooftile Coatings
standard
bull Can increase solar reflectance by up to 05 bull Gain greatest for dark colors
∆R=037 ∆R=026 ∆R=023 ∆R=015 ∆R=029 ∆R=029
21
22
Increasing solar reflectance of fiberglass asphalt shingles prototypes
cooler ρ=028
ρ = solar reflectance
ρ=036
warmer ρ=023 ρ=027 ρ=028
ρ=037
23
Increasing solar reflectance of fiberglass asphalt shingles Elk Prestiquereg Cool Color Series
24
Increasing solar reflectance of metal roofing BASF Ultra-Coolreg metal roof coatings
numbers denote solar reflectances cooler (warmer)
Courtesy BASF
Industrial Coatings
25
Cool Metal Roofs
Increasing solar reflectance of clay tiles MCA Clay Tile cool colored tiles
26
Model Color Initial solar reflectance
Solar reflectance after 3 years
Weathered Green Blend
043 049
Natural Red 043 038
Brick Red 042 040
White Buff 068 056
Tobacco 043 041
27
Non-residential building energy and equipment savings15-year net present value of savings ($1000 ft2)
30-year net present value of savings ($1000 ft2) concrete tile roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 39 53 37 56 42 58 39 71 74 60 64 55 68 66 66 60
Energy 406 917 726 992 781 1593 1432 1822 1862 1390 1190 1109 1355 1477 1900 791 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
28
30-year net present value of savings ($1000 ft2) metal roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 41 57 41 61 47 57 48 83 88 65 71 60 73 72 71 65
Energy 495 1053 847 1128 919 1870 1692 2141 2181 1561 1330 1243 1507 1648 2093 918 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
29
Cool Roofs Standards bull Building standards for reflective roofs
- American Society of Heating and Air-conditioning Engineers (ASHRAE) New commercial and residential buildings
- Many state California Georgia Florida Hawaii hellip bull Air quality standards
- South Coast AQMD - SF Bay Area AQMD - EPArsquos SIP (State Implementation Plans)
30
White Roofs Programs in California
bull One Time CEC Incentive -- $20 Million frac34 at $015 to $020 per square foot
bull California utilities incentives bull 2001 to 2005-- credits white and cool colored
roofs bull 2005 requires cool flat roofs bull 2008 may require cool roofs for all buildings
31
Cool Roof Programs around the World
32
bull US bull Europe bull Asia bull Middle East
bull China bull India (Hyderabad
demos see graphs funded by USAID)
Cool Roofs to Save CO2
33
Cool Surfaces also Cool the Globe
bull Cool roof standards are designed to reduce ac demand save money and save emissions In Los Angeles they will eventually save ~$100000 per hour
bull Annual savings in the US = $1-2B ~ 7 M tons CO2
bull Annual savings in the world = $10-15B ~ 100 M tons CO2
bull But higher albedo surfaces (roofs and pavements) directly cool the world (001 K) quite independent of avoided CO2 So we discuss the effect of cool surfaces for tropical temperate cities
34
35
100 Largest Cities have 670 M People
0
1000
2000
3000
4000
5000
0 10 20 30 40
Population (M)
Are
a D
ensi
ty(m
2 per
son)
Mean = 560 m2p Med = 430 m2p
Tokyo
Mexico City New York City Mumbai Satildeo Paulo
Dense Urban Areas are 1 of Land
bull Area of the Earth = 511x1012 m2
bull Land Area (29) = 148x1012 m2 [1] bull Area of the 100 largest cities = 038x1012 m2 = 026
of Land Area for 670 M people bull Assuming 3B live in urban area urban areas =
[3000670] x 026 = 12 of land bull But smaller cities have lower population density
hence urban areas = 2 of land bull Dense developed urban areas only 1 of land [2]
36
Potentials to Increase Urban Albdeo is 01
bull Typical urban area is 25 roof and 35 paved surfaces
bull Roof albedo can increase by 025 for a net change of 025x025=0063
bull Paved surfaces albedo can increase by 015 for a net change of 035x015=0052
bull Net urban area albedo change at least 010
37
Effect of Increasing Urban Albedo by 01
bull Net Change in Global albedo = [CityLand]x[LandGlobe]x∆a = [2]x[1]x∆a = 001 x 029 x01 = 00003 [3]
bull The effect on global temperature frac34 Using three different calculations is about 001K
38
Carbon Equivalency bull Modelers estimate a warming of 2K in 60 years so
003Kyear bull Change of 01 in urban albedo will result in 001K a delay
of ~03 years in global warming bull Worldrsquos current rate of CO2 emissions =
25 G tonsyear (41 tonsyear per person) bull Worldrsquos rate of CO2 emissions averaged over next 60
years = 40 G tonsyear bull Hence 03 years delay is worth 12 Gt CO2 ~ 200 Mt
CO2year
39
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
15
Cool Roof Technologies
flat white
pitched white
pitched cool amp colored
Old New
16
Cool Colors Reflect Invisible Near-Infrared Sunlight
Cool and Standard Brown Metal Roofing Panels
bull Solar reflectance ~ 02 higher bull Afternoon surface temperature ~ 10ordmC lower
17
Courtesy BASF
Coatings
18
Example Dioxazine Purple Over Various Undercoats
bull Two-layer system frac34 top coat thin layer of dioxazine purple (14-27 microm) frac34 undercoat or substrate
aluminum foil (~ 25 microm) opaque white paint (~1000 microm) non-opaque white paint (~ 25 microm) opaque black paint (~ 25 microm)
purple over
aluminum foil
purple over
opaque white paint
purple over
non-opaque white paint
purple over
opaque black paint
19
Dioxazine Purple Reflectances
over aluminum Rsolar = 041
over opaque white Rsolar = 042
over non-opaque white Rsolar = 030
over opaque black Rsolar = 005
20
National Labs and Industrial Partnership bull Program is sponsored by
CECPIER bull ORNL and LBNL are teaming
with industry bull Broad industrial partnership
bull Industry partners frac34 3M (ganules) frac34 American Roof Tile Coating frac34 BASF (metal) frac34 Custom-Bilt Metals frac34 Elk Manufacturing (shingles) frac34 Ferro frac34 GAF (shingles) frac34 Hanson Roof Tile frac34 ISP Minerals (ganules) frac34 MCA (tiles) frac34 Monier Lifetile (tile) frac34 Shepherd Color Company
Cool and Standard Color-Matched Concrete Tiles
cool Courtesy American Rooftile Coatings
standard
bull Can increase solar reflectance by up to 05 bull Gain greatest for dark colors
∆R=037 ∆R=026 ∆R=023 ∆R=015 ∆R=029 ∆R=029
21
22
Increasing solar reflectance of fiberglass asphalt shingles prototypes
cooler ρ=028
ρ = solar reflectance
ρ=036
warmer ρ=023 ρ=027 ρ=028
ρ=037
23
Increasing solar reflectance of fiberglass asphalt shingles Elk Prestiquereg Cool Color Series
24
Increasing solar reflectance of metal roofing BASF Ultra-Coolreg metal roof coatings
numbers denote solar reflectances cooler (warmer)
Courtesy BASF
Industrial Coatings
25
Cool Metal Roofs
Increasing solar reflectance of clay tiles MCA Clay Tile cool colored tiles
26
Model Color Initial solar reflectance
Solar reflectance after 3 years
Weathered Green Blend
043 049
Natural Red 043 038
Brick Red 042 040
White Buff 068 056
Tobacco 043 041
27
Non-residential building energy and equipment savings15-year net present value of savings ($1000 ft2)
30-year net present value of savings ($1000 ft2) concrete tile roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 39 53 37 56 42 58 39 71 74 60 64 55 68 66 66 60
Energy 406 917 726 992 781 1593 1432 1822 1862 1390 1190 1109 1355 1477 1900 791 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
28
30-year net present value of savings ($1000 ft2) metal roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 41 57 41 61 47 57 48 83 88 65 71 60 73 72 71 65
Energy 495 1053 847 1128 919 1870 1692 2141 2181 1561 1330 1243 1507 1648 2093 918 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
29
Cool Roofs Standards bull Building standards for reflective roofs
- American Society of Heating and Air-conditioning Engineers (ASHRAE) New commercial and residential buildings
- Many state California Georgia Florida Hawaii hellip bull Air quality standards
- South Coast AQMD - SF Bay Area AQMD - EPArsquos SIP (State Implementation Plans)
30
White Roofs Programs in California
bull One Time CEC Incentive -- $20 Million frac34 at $015 to $020 per square foot
bull California utilities incentives bull 2001 to 2005-- credits white and cool colored
roofs bull 2005 requires cool flat roofs bull 2008 may require cool roofs for all buildings
31
Cool Roof Programs around the World
32
bull US bull Europe bull Asia bull Middle East
bull China bull India (Hyderabad
demos see graphs funded by USAID)
Cool Roofs to Save CO2
33
Cool Surfaces also Cool the Globe
bull Cool roof standards are designed to reduce ac demand save money and save emissions In Los Angeles they will eventually save ~$100000 per hour
bull Annual savings in the US = $1-2B ~ 7 M tons CO2
bull Annual savings in the world = $10-15B ~ 100 M tons CO2
bull But higher albedo surfaces (roofs and pavements) directly cool the world (001 K) quite independent of avoided CO2 So we discuss the effect of cool surfaces for tropical temperate cities
34
35
100 Largest Cities have 670 M People
0
1000
2000
3000
4000
5000
0 10 20 30 40
Population (M)
Are
a D
ensi
ty(m
2 per
son)
Mean = 560 m2p Med = 430 m2p
Tokyo
Mexico City New York City Mumbai Satildeo Paulo
Dense Urban Areas are 1 of Land
bull Area of the Earth = 511x1012 m2
bull Land Area (29) = 148x1012 m2 [1] bull Area of the 100 largest cities = 038x1012 m2 = 026
of Land Area for 670 M people bull Assuming 3B live in urban area urban areas =
[3000670] x 026 = 12 of land bull But smaller cities have lower population density
hence urban areas = 2 of land bull Dense developed urban areas only 1 of land [2]
36
Potentials to Increase Urban Albdeo is 01
bull Typical urban area is 25 roof and 35 paved surfaces
bull Roof albedo can increase by 025 for a net change of 025x025=0063
bull Paved surfaces albedo can increase by 015 for a net change of 035x015=0052
bull Net urban area albedo change at least 010
37
Effect of Increasing Urban Albedo by 01
bull Net Change in Global albedo = [CityLand]x[LandGlobe]x∆a = [2]x[1]x∆a = 001 x 029 x01 = 00003 [3]
bull The effect on global temperature frac34 Using three different calculations is about 001K
38
Carbon Equivalency bull Modelers estimate a warming of 2K in 60 years so
003Kyear bull Change of 01 in urban albedo will result in 001K a delay
of ~03 years in global warming bull Worldrsquos current rate of CO2 emissions =
25 G tonsyear (41 tonsyear per person) bull Worldrsquos rate of CO2 emissions averaged over next 60
years = 40 G tonsyear bull Hence 03 years delay is worth 12 Gt CO2 ~ 200 Mt
CO2year
39
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
16
Cool Colors Reflect Invisible Near-Infrared Sunlight
Cool and Standard Brown Metal Roofing Panels
bull Solar reflectance ~ 02 higher bull Afternoon surface temperature ~ 10ordmC lower
17
Courtesy BASF
Coatings
18
Example Dioxazine Purple Over Various Undercoats
bull Two-layer system frac34 top coat thin layer of dioxazine purple (14-27 microm) frac34 undercoat or substrate
aluminum foil (~ 25 microm) opaque white paint (~1000 microm) non-opaque white paint (~ 25 microm) opaque black paint (~ 25 microm)
purple over
aluminum foil
purple over
opaque white paint
purple over
non-opaque white paint
purple over
opaque black paint
19
Dioxazine Purple Reflectances
over aluminum Rsolar = 041
over opaque white Rsolar = 042
over non-opaque white Rsolar = 030
over opaque black Rsolar = 005
20
National Labs and Industrial Partnership bull Program is sponsored by
CECPIER bull ORNL and LBNL are teaming
with industry bull Broad industrial partnership
bull Industry partners frac34 3M (ganules) frac34 American Roof Tile Coating frac34 BASF (metal) frac34 Custom-Bilt Metals frac34 Elk Manufacturing (shingles) frac34 Ferro frac34 GAF (shingles) frac34 Hanson Roof Tile frac34 ISP Minerals (ganules) frac34 MCA (tiles) frac34 Monier Lifetile (tile) frac34 Shepherd Color Company
Cool and Standard Color-Matched Concrete Tiles
cool Courtesy American Rooftile Coatings
standard
bull Can increase solar reflectance by up to 05 bull Gain greatest for dark colors
∆R=037 ∆R=026 ∆R=023 ∆R=015 ∆R=029 ∆R=029
21
22
Increasing solar reflectance of fiberglass asphalt shingles prototypes
cooler ρ=028
ρ = solar reflectance
ρ=036
warmer ρ=023 ρ=027 ρ=028
ρ=037
23
Increasing solar reflectance of fiberglass asphalt shingles Elk Prestiquereg Cool Color Series
24
Increasing solar reflectance of metal roofing BASF Ultra-Coolreg metal roof coatings
numbers denote solar reflectances cooler (warmer)
Courtesy BASF
Industrial Coatings
25
Cool Metal Roofs
Increasing solar reflectance of clay tiles MCA Clay Tile cool colored tiles
26
Model Color Initial solar reflectance
Solar reflectance after 3 years
Weathered Green Blend
043 049
Natural Red 043 038
Brick Red 042 040
White Buff 068 056
Tobacco 043 041
27
Non-residential building energy and equipment savings15-year net present value of savings ($1000 ft2)
30-year net present value of savings ($1000 ft2) concrete tile roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 39 53 37 56 42 58 39 71 74 60 64 55 68 66 66 60
Energy 406 917 726 992 781 1593 1432 1822 1862 1390 1190 1109 1355 1477 1900 791 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
28
30-year net present value of savings ($1000 ft2) metal roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 41 57 41 61 47 57 48 83 88 65 71 60 73 72 71 65
Energy 495 1053 847 1128 919 1870 1692 2141 2181 1561 1330 1243 1507 1648 2093 918 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
29
Cool Roofs Standards bull Building standards for reflective roofs
- American Society of Heating and Air-conditioning Engineers (ASHRAE) New commercial and residential buildings
- Many state California Georgia Florida Hawaii hellip bull Air quality standards
- South Coast AQMD - SF Bay Area AQMD - EPArsquos SIP (State Implementation Plans)
30
White Roofs Programs in California
bull One Time CEC Incentive -- $20 Million frac34 at $015 to $020 per square foot
bull California utilities incentives bull 2001 to 2005-- credits white and cool colored
roofs bull 2005 requires cool flat roofs bull 2008 may require cool roofs for all buildings
31
Cool Roof Programs around the World
32
bull US bull Europe bull Asia bull Middle East
bull China bull India (Hyderabad
demos see graphs funded by USAID)
Cool Roofs to Save CO2
33
Cool Surfaces also Cool the Globe
bull Cool roof standards are designed to reduce ac demand save money and save emissions In Los Angeles they will eventually save ~$100000 per hour
bull Annual savings in the US = $1-2B ~ 7 M tons CO2
bull Annual savings in the world = $10-15B ~ 100 M tons CO2
bull But higher albedo surfaces (roofs and pavements) directly cool the world (001 K) quite independent of avoided CO2 So we discuss the effect of cool surfaces for tropical temperate cities
34
35
100 Largest Cities have 670 M People
0
1000
2000
3000
4000
5000
0 10 20 30 40
Population (M)
Are
a D
ensi
ty(m
2 per
son)
Mean = 560 m2p Med = 430 m2p
Tokyo
Mexico City New York City Mumbai Satildeo Paulo
Dense Urban Areas are 1 of Land
bull Area of the Earth = 511x1012 m2
bull Land Area (29) = 148x1012 m2 [1] bull Area of the 100 largest cities = 038x1012 m2 = 026
of Land Area for 670 M people bull Assuming 3B live in urban area urban areas =
[3000670] x 026 = 12 of land bull But smaller cities have lower population density
hence urban areas = 2 of land bull Dense developed urban areas only 1 of land [2]
36
Potentials to Increase Urban Albdeo is 01
bull Typical urban area is 25 roof and 35 paved surfaces
bull Roof albedo can increase by 025 for a net change of 025x025=0063
bull Paved surfaces albedo can increase by 015 for a net change of 035x015=0052
bull Net urban area albedo change at least 010
37
Effect of Increasing Urban Albedo by 01
bull Net Change in Global albedo = [CityLand]x[LandGlobe]x∆a = [2]x[1]x∆a = 001 x 029 x01 = 00003 [3]
bull The effect on global temperature frac34 Using three different calculations is about 001K
38
Carbon Equivalency bull Modelers estimate a warming of 2K in 60 years so
003Kyear bull Change of 01 in urban albedo will result in 001K a delay
of ~03 years in global warming bull Worldrsquos current rate of CO2 emissions =
25 G tonsyear (41 tonsyear per person) bull Worldrsquos rate of CO2 emissions averaged over next 60
years = 40 G tonsyear bull Hence 03 years delay is worth 12 Gt CO2 ~ 200 Mt
CO2year
39
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
Cool and Standard Brown Metal Roofing Panels
bull Solar reflectance ~ 02 higher bull Afternoon surface temperature ~ 10ordmC lower
17
Courtesy BASF
Coatings
18
Example Dioxazine Purple Over Various Undercoats
bull Two-layer system frac34 top coat thin layer of dioxazine purple (14-27 microm) frac34 undercoat or substrate
aluminum foil (~ 25 microm) opaque white paint (~1000 microm) non-opaque white paint (~ 25 microm) opaque black paint (~ 25 microm)
purple over
aluminum foil
purple over
opaque white paint
purple over
non-opaque white paint
purple over
opaque black paint
19
Dioxazine Purple Reflectances
over aluminum Rsolar = 041
over opaque white Rsolar = 042
over non-opaque white Rsolar = 030
over opaque black Rsolar = 005
20
National Labs and Industrial Partnership bull Program is sponsored by
CECPIER bull ORNL and LBNL are teaming
with industry bull Broad industrial partnership
bull Industry partners frac34 3M (ganules) frac34 American Roof Tile Coating frac34 BASF (metal) frac34 Custom-Bilt Metals frac34 Elk Manufacturing (shingles) frac34 Ferro frac34 GAF (shingles) frac34 Hanson Roof Tile frac34 ISP Minerals (ganules) frac34 MCA (tiles) frac34 Monier Lifetile (tile) frac34 Shepherd Color Company
Cool and Standard Color-Matched Concrete Tiles
cool Courtesy American Rooftile Coatings
standard
bull Can increase solar reflectance by up to 05 bull Gain greatest for dark colors
∆R=037 ∆R=026 ∆R=023 ∆R=015 ∆R=029 ∆R=029
21
22
Increasing solar reflectance of fiberglass asphalt shingles prototypes
cooler ρ=028
ρ = solar reflectance
ρ=036
warmer ρ=023 ρ=027 ρ=028
ρ=037
23
Increasing solar reflectance of fiberglass asphalt shingles Elk Prestiquereg Cool Color Series
24
Increasing solar reflectance of metal roofing BASF Ultra-Coolreg metal roof coatings
numbers denote solar reflectances cooler (warmer)
Courtesy BASF
Industrial Coatings
25
Cool Metal Roofs
Increasing solar reflectance of clay tiles MCA Clay Tile cool colored tiles
26
Model Color Initial solar reflectance
Solar reflectance after 3 years
Weathered Green Blend
043 049
Natural Red 043 038
Brick Red 042 040
White Buff 068 056
Tobacco 043 041
27
Non-residential building energy and equipment savings15-year net present value of savings ($1000 ft2)
30-year net present value of savings ($1000 ft2) concrete tile roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 39 53 37 56 42 58 39 71 74 60 64 55 68 66 66 60
Energy 406 917 726 992 781 1593 1432 1822 1862 1390 1190 1109 1355 1477 1900 791 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
28
30-year net present value of savings ($1000 ft2) metal roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 41 57 41 61 47 57 48 83 88 65 71 60 73 72 71 65
Energy 495 1053 847 1128 919 1870 1692 2141 2181 1561 1330 1243 1507 1648 2093 918 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
29
Cool Roofs Standards bull Building standards for reflective roofs
- American Society of Heating and Air-conditioning Engineers (ASHRAE) New commercial and residential buildings
- Many state California Georgia Florida Hawaii hellip bull Air quality standards
- South Coast AQMD - SF Bay Area AQMD - EPArsquos SIP (State Implementation Plans)
30
White Roofs Programs in California
bull One Time CEC Incentive -- $20 Million frac34 at $015 to $020 per square foot
bull California utilities incentives bull 2001 to 2005-- credits white and cool colored
roofs bull 2005 requires cool flat roofs bull 2008 may require cool roofs for all buildings
31
Cool Roof Programs around the World
32
bull US bull Europe bull Asia bull Middle East
bull China bull India (Hyderabad
demos see graphs funded by USAID)
Cool Roofs to Save CO2
33
Cool Surfaces also Cool the Globe
bull Cool roof standards are designed to reduce ac demand save money and save emissions In Los Angeles they will eventually save ~$100000 per hour
bull Annual savings in the US = $1-2B ~ 7 M tons CO2
bull Annual savings in the world = $10-15B ~ 100 M tons CO2
bull But higher albedo surfaces (roofs and pavements) directly cool the world (001 K) quite independent of avoided CO2 So we discuss the effect of cool surfaces for tropical temperate cities
34
35
100 Largest Cities have 670 M People
0
1000
2000
3000
4000
5000
0 10 20 30 40
Population (M)
Are
a D
ensi
ty(m
2 per
son)
Mean = 560 m2p Med = 430 m2p
Tokyo
Mexico City New York City Mumbai Satildeo Paulo
Dense Urban Areas are 1 of Land
bull Area of the Earth = 511x1012 m2
bull Land Area (29) = 148x1012 m2 [1] bull Area of the 100 largest cities = 038x1012 m2 = 026
of Land Area for 670 M people bull Assuming 3B live in urban area urban areas =
[3000670] x 026 = 12 of land bull But smaller cities have lower population density
hence urban areas = 2 of land bull Dense developed urban areas only 1 of land [2]
36
Potentials to Increase Urban Albdeo is 01
bull Typical urban area is 25 roof and 35 paved surfaces
bull Roof albedo can increase by 025 for a net change of 025x025=0063
bull Paved surfaces albedo can increase by 015 for a net change of 035x015=0052
bull Net urban area albedo change at least 010
37
Effect of Increasing Urban Albedo by 01
bull Net Change in Global albedo = [CityLand]x[LandGlobe]x∆a = [2]x[1]x∆a = 001 x 029 x01 = 00003 [3]
bull The effect on global temperature frac34 Using three different calculations is about 001K
38
Carbon Equivalency bull Modelers estimate a warming of 2K in 60 years so
003Kyear bull Change of 01 in urban albedo will result in 001K a delay
of ~03 years in global warming bull Worldrsquos current rate of CO2 emissions =
25 G tonsyear (41 tonsyear per person) bull Worldrsquos rate of CO2 emissions averaged over next 60
years = 40 G tonsyear bull Hence 03 years delay is worth 12 Gt CO2 ~ 200 Mt
CO2year
39
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
18
Example Dioxazine Purple Over Various Undercoats
bull Two-layer system frac34 top coat thin layer of dioxazine purple (14-27 microm) frac34 undercoat or substrate
aluminum foil (~ 25 microm) opaque white paint (~1000 microm) non-opaque white paint (~ 25 microm) opaque black paint (~ 25 microm)
purple over
aluminum foil
purple over
opaque white paint
purple over
non-opaque white paint
purple over
opaque black paint
19
Dioxazine Purple Reflectances
over aluminum Rsolar = 041
over opaque white Rsolar = 042
over non-opaque white Rsolar = 030
over opaque black Rsolar = 005
20
National Labs and Industrial Partnership bull Program is sponsored by
CECPIER bull ORNL and LBNL are teaming
with industry bull Broad industrial partnership
bull Industry partners frac34 3M (ganules) frac34 American Roof Tile Coating frac34 BASF (metal) frac34 Custom-Bilt Metals frac34 Elk Manufacturing (shingles) frac34 Ferro frac34 GAF (shingles) frac34 Hanson Roof Tile frac34 ISP Minerals (ganules) frac34 MCA (tiles) frac34 Monier Lifetile (tile) frac34 Shepherd Color Company
Cool and Standard Color-Matched Concrete Tiles
cool Courtesy American Rooftile Coatings
standard
bull Can increase solar reflectance by up to 05 bull Gain greatest for dark colors
∆R=037 ∆R=026 ∆R=023 ∆R=015 ∆R=029 ∆R=029
21
22
Increasing solar reflectance of fiberglass asphalt shingles prototypes
cooler ρ=028
ρ = solar reflectance
ρ=036
warmer ρ=023 ρ=027 ρ=028
ρ=037
23
Increasing solar reflectance of fiberglass asphalt shingles Elk Prestiquereg Cool Color Series
24
Increasing solar reflectance of metal roofing BASF Ultra-Coolreg metal roof coatings
numbers denote solar reflectances cooler (warmer)
Courtesy BASF
Industrial Coatings
25
Cool Metal Roofs
Increasing solar reflectance of clay tiles MCA Clay Tile cool colored tiles
26
Model Color Initial solar reflectance
Solar reflectance after 3 years
Weathered Green Blend
043 049
Natural Red 043 038
Brick Red 042 040
White Buff 068 056
Tobacco 043 041
27
Non-residential building energy and equipment savings15-year net present value of savings ($1000 ft2)
30-year net present value of savings ($1000 ft2) concrete tile roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 39 53 37 56 42 58 39 71 74 60 64 55 68 66 66 60
Energy 406 917 726 992 781 1593 1432 1822 1862 1390 1190 1109 1355 1477 1900 791 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
28
30-year net present value of savings ($1000 ft2) metal roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 41 57 41 61 47 57 48 83 88 65 71 60 73 72 71 65
Energy 495 1053 847 1128 919 1870 1692 2141 2181 1561 1330 1243 1507 1648 2093 918 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
29
Cool Roofs Standards bull Building standards for reflective roofs
- American Society of Heating and Air-conditioning Engineers (ASHRAE) New commercial and residential buildings
- Many state California Georgia Florida Hawaii hellip bull Air quality standards
- South Coast AQMD - SF Bay Area AQMD - EPArsquos SIP (State Implementation Plans)
30
White Roofs Programs in California
bull One Time CEC Incentive -- $20 Million frac34 at $015 to $020 per square foot
bull California utilities incentives bull 2001 to 2005-- credits white and cool colored
roofs bull 2005 requires cool flat roofs bull 2008 may require cool roofs for all buildings
31
Cool Roof Programs around the World
32
bull US bull Europe bull Asia bull Middle East
bull China bull India (Hyderabad
demos see graphs funded by USAID)
Cool Roofs to Save CO2
33
Cool Surfaces also Cool the Globe
bull Cool roof standards are designed to reduce ac demand save money and save emissions In Los Angeles they will eventually save ~$100000 per hour
bull Annual savings in the US = $1-2B ~ 7 M tons CO2
bull Annual savings in the world = $10-15B ~ 100 M tons CO2
bull But higher albedo surfaces (roofs and pavements) directly cool the world (001 K) quite independent of avoided CO2 So we discuss the effect of cool surfaces for tropical temperate cities
34
35
100 Largest Cities have 670 M People
0
1000
2000
3000
4000
5000
0 10 20 30 40
Population (M)
Are
a D
ensi
ty(m
2 per
son)
Mean = 560 m2p Med = 430 m2p
Tokyo
Mexico City New York City Mumbai Satildeo Paulo
Dense Urban Areas are 1 of Land
bull Area of the Earth = 511x1012 m2
bull Land Area (29) = 148x1012 m2 [1] bull Area of the 100 largest cities = 038x1012 m2 = 026
of Land Area for 670 M people bull Assuming 3B live in urban area urban areas =
[3000670] x 026 = 12 of land bull But smaller cities have lower population density
hence urban areas = 2 of land bull Dense developed urban areas only 1 of land [2]
36
Potentials to Increase Urban Albdeo is 01
bull Typical urban area is 25 roof and 35 paved surfaces
bull Roof albedo can increase by 025 for a net change of 025x025=0063
bull Paved surfaces albedo can increase by 015 for a net change of 035x015=0052
bull Net urban area albedo change at least 010
37
Effect of Increasing Urban Albedo by 01
bull Net Change in Global albedo = [CityLand]x[LandGlobe]x∆a = [2]x[1]x∆a = 001 x 029 x01 = 00003 [3]
bull The effect on global temperature frac34 Using three different calculations is about 001K
38
Carbon Equivalency bull Modelers estimate a warming of 2K in 60 years so
003Kyear bull Change of 01 in urban albedo will result in 001K a delay
of ~03 years in global warming bull Worldrsquos current rate of CO2 emissions =
25 G tonsyear (41 tonsyear per person) bull Worldrsquos rate of CO2 emissions averaged over next 60
years = 40 G tonsyear bull Hence 03 years delay is worth 12 Gt CO2 ~ 200 Mt
CO2year
39
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
19
Dioxazine Purple Reflectances
over aluminum Rsolar = 041
over opaque white Rsolar = 042
over non-opaque white Rsolar = 030
over opaque black Rsolar = 005
20
National Labs and Industrial Partnership bull Program is sponsored by
CECPIER bull ORNL and LBNL are teaming
with industry bull Broad industrial partnership
bull Industry partners frac34 3M (ganules) frac34 American Roof Tile Coating frac34 BASF (metal) frac34 Custom-Bilt Metals frac34 Elk Manufacturing (shingles) frac34 Ferro frac34 GAF (shingles) frac34 Hanson Roof Tile frac34 ISP Minerals (ganules) frac34 MCA (tiles) frac34 Monier Lifetile (tile) frac34 Shepherd Color Company
Cool and Standard Color-Matched Concrete Tiles
cool Courtesy American Rooftile Coatings
standard
bull Can increase solar reflectance by up to 05 bull Gain greatest for dark colors
∆R=037 ∆R=026 ∆R=023 ∆R=015 ∆R=029 ∆R=029
21
22
Increasing solar reflectance of fiberglass asphalt shingles prototypes
cooler ρ=028
ρ = solar reflectance
ρ=036
warmer ρ=023 ρ=027 ρ=028
ρ=037
23
Increasing solar reflectance of fiberglass asphalt shingles Elk Prestiquereg Cool Color Series
24
Increasing solar reflectance of metal roofing BASF Ultra-Coolreg metal roof coatings
numbers denote solar reflectances cooler (warmer)
Courtesy BASF
Industrial Coatings
25
Cool Metal Roofs
Increasing solar reflectance of clay tiles MCA Clay Tile cool colored tiles
26
Model Color Initial solar reflectance
Solar reflectance after 3 years
Weathered Green Blend
043 049
Natural Red 043 038
Brick Red 042 040
White Buff 068 056
Tobacco 043 041
27
Non-residential building energy and equipment savings15-year net present value of savings ($1000 ft2)
30-year net present value of savings ($1000 ft2) concrete tile roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 39 53 37 56 42 58 39 71 74 60 64 55 68 66 66 60
Energy 406 917 726 992 781 1593 1432 1822 1862 1390 1190 1109 1355 1477 1900 791 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
28
30-year net present value of savings ($1000 ft2) metal roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 41 57 41 61 47 57 48 83 88 65 71 60 73 72 71 65
Energy 495 1053 847 1128 919 1870 1692 2141 2181 1561 1330 1243 1507 1648 2093 918 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
29
Cool Roofs Standards bull Building standards for reflective roofs
- American Society of Heating and Air-conditioning Engineers (ASHRAE) New commercial and residential buildings
- Many state California Georgia Florida Hawaii hellip bull Air quality standards
- South Coast AQMD - SF Bay Area AQMD - EPArsquos SIP (State Implementation Plans)
30
White Roofs Programs in California
bull One Time CEC Incentive -- $20 Million frac34 at $015 to $020 per square foot
bull California utilities incentives bull 2001 to 2005-- credits white and cool colored
roofs bull 2005 requires cool flat roofs bull 2008 may require cool roofs for all buildings
31
Cool Roof Programs around the World
32
bull US bull Europe bull Asia bull Middle East
bull China bull India (Hyderabad
demos see graphs funded by USAID)
Cool Roofs to Save CO2
33
Cool Surfaces also Cool the Globe
bull Cool roof standards are designed to reduce ac demand save money and save emissions In Los Angeles they will eventually save ~$100000 per hour
bull Annual savings in the US = $1-2B ~ 7 M tons CO2
bull Annual savings in the world = $10-15B ~ 100 M tons CO2
bull But higher albedo surfaces (roofs and pavements) directly cool the world (001 K) quite independent of avoided CO2 So we discuss the effect of cool surfaces for tropical temperate cities
34
35
100 Largest Cities have 670 M People
0
1000
2000
3000
4000
5000
0 10 20 30 40
Population (M)
Are
a D
ensi
ty(m
2 per
son)
Mean = 560 m2p Med = 430 m2p
Tokyo
Mexico City New York City Mumbai Satildeo Paulo
Dense Urban Areas are 1 of Land
bull Area of the Earth = 511x1012 m2
bull Land Area (29) = 148x1012 m2 [1] bull Area of the 100 largest cities = 038x1012 m2 = 026
of Land Area for 670 M people bull Assuming 3B live in urban area urban areas =
[3000670] x 026 = 12 of land bull But smaller cities have lower population density
hence urban areas = 2 of land bull Dense developed urban areas only 1 of land [2]
36
Potentials to Increase Urban Albdeo is 01
bull Typical urban area is 25 roof and 35 paved surfaces
bull Roof albedo can increase by 025 for a net change of 025x025=0063
bull Paved surfaces albedo can increase by 015 for a net change of 035x015=0052
bull Net urban area albedo change at least 010
37
Effect of Increasing Urban Albedo by 01
bull Net Change in Global albedo = [CityLand]x[LandGlobe]x∆a = [2]x[1]x∆a = 001 x 029 x01 = 00003 [3]
bull The effect on global temperature frac34 Using three different calculations is about 001K
38
Carbon Equivalency bull Modelers estimate a warming of 2K in 60 years so
003Kyear bull Change of 01 in urban albedo will result in 001K a delay
of ~03 years in global warming bull Worldrsquos current rate of CO2 emissions =
25 G tonsyear (41 tonsyear per person) bull Worldrsquos rate of CO2 emissions averaged over next 60
years = 40 G tonsyear bull Hence 03 years delay is worth 12 Gt CO2 ~ 200 Mt
CO2year
39
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
20
National Labs and Industrial Partnership bull Program is sponsored by
CECPIER bull ORNL and LBNL are teaming
with industry bull Broad industrial partnership
bull Industry partners frac34 3M (ganules) frac34 American Roof Tile Coating frac34 BASF (metal) frac34 Custom-Bilt Metals frac34 Elk Manufacturing (shingles) frac34 Ferro frac34 GAF (shingles) frac34 Hanson Roof Tile frac34 ISP Minerals (ganules) frac34 MCA (tiles) frac34 Monier Lifetile (tile) frac34 Shepherd Color Company
Cool and Standard Color-Matched Concrete Tiles
cool Courtesy American Rooftile Coatings
standard
bull Can increase solar reflectance by up to 05 bull Gain greatest for dark colors
∆R=037 ∆R=026 ∆R=023 ∆R=015 ∆R=029 ∆R=029
21
22
Increasing solar reflectance of fiberglass asphalt shingles prototypes
cooler ρ=028
ρ = solar reflectance
ρ=036
warmer ρ=023 ρ=027 ρ=028
ρ=037
23
Increasing solar reflectance of fiberglass asphalt shingles Elk Prestiquereg Cool Color Series
24
Increasing solar reflectance of metal roofing BASF Ultra-Coolreg metal roof coatings
numbers denote solar reflectances cooler (warmer)
Courtesy BASF
Industrial Coatings
25
Cool Metal Roofs
Increasing solar reflectance of clay tiles MCA Clay Tile cool colored tiles
26
Model Color Initial solar reflectance
Solar reflectance after 3 years
Weathered Green Blend
043 049
Natural Red 043 038
Brick Red 042 040
White Buff 068 056
Tobacco 043 041
27
Non-residential building energy and equipment savings15-year net present value of savings ($1000 ft2)
30-year net present value of savings ($1000 ft2) concrete tile roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 39 53 37 56 42 58 39 71 74 60 64 55 68 66 66 60
Energy 406 917 726 992 781 1593 1432 1822 1862 1390 1190 1109 1355 1477 1900 791 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
28
30-year net present value of savings ($1000 ft2) metal roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 41 57 41 61 47 57 48 83 88 65 71 60 73 72 71 65
Energy 495 1053 847 1128 919 1870 1692 2141 2181 1561 1330 1243 1507 1648 2093 918 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
29
Cool Roofs Standards bull Building standards for reflective roofs
- American Society of Heating and Air-conditioning Engineers (ASHRAE) New commercial and residential buildings
- Many state California Georgia Florida Hawaii hellip bull Air quality standards
- South Coast AQMD - SF Bay Area AQMD - EPArsquos SIP (State Implementation Plans)
30
White Roofs Programs in California
bull One Time CEC Incentive -- $20 Million frac34 at $015 to $020 per square foot
bull California utilities incentives bull 2001 to 2005-- credits white and cool colored
roofs bull 2005 requires cool flat roofs bull 2008 may require cool roofs for all buildings
31
Cool Roof Programs around the World
32
bull US bull Europe bull Asia bull Middle East
bull China bull India (Hyderabad
demos see graphs funded by USAID)
Cool Roofs to Save CO2
33
Cool Surfaces also Cool the Globe
bull Cool roof standards are designed to reduce ac demand save money and save emissions In Los Angeles they will eventually save ~$100000 per hour
bull Annual savings in the US = $1-2B ~ 7 M tons CO2
bull Annual savings in the world = $10-15B ~ 100 M tons CO2
bull But higher albedo surfaces (roofs and pavements) directly cool the world (001 K) quite independent of avoided CO2 So we discuss the effect of cool surfaces for tropical temperate cities
34
35
100 Largest Cities have 670 M People
0
1000
2000
3000
4000
5000
0 10 20 30 40
Population (M)
Are
a D
ensi
ty(m
2 per
son)
Mean = 560 m2p Med = 430 m2p
Tokyo
Mexico City New York City Mumbai Satildeo Paulo
Dense Urban Areas are 1 of Land
bull Area of the Earth = 511x1012 m2
bull Land Area (29) = 148x1012 m2 [1] bull Area of the 100 largest cities = 038x1012 m2 = 026
of Land Area for 670 M people bull Assuming 3B live in urban area urban areas =
[3000670] x 026 = 12 of land bull But smaller cities have lower population density
hence urban areas = 2 of land bull Dense developed urban areas only 1 of land [2]
36
Potentials to Increase Urban Albdeo is 01
bull Typical urban area is 25 roof and 35 paved surfaces
bull Roof albedo can increase by 025 for a net change of 025x025=0063
bull Paved surfaces albedo can increase by 015 for a net change of 035x015=0052
bull Net urban area albedo change at least 010
37
Effect of Increasing Urban Albedo by 01
bull Net Change in Global albedo = [CityLand]x[LandGlobe]x∆a = [2]x[1]x∆a = 001 x 029 x01 = 00003 [3]
bull The effect on global temperature frac34 Using three different calculations is about 001K
38
Carbon Equivalency bull Modelers estimate a warming of 2K in 60 years so
003Kyear bull Change of 01 in urban albedo will result in 001K a delay
of ~03 years in global warming bull Worldrsquos current rate of CO2 emissions =
25 G tonsyear (41 tonsyear per person) bull Worldrsquos rate of CO2 emissions averaged over next 60
years = 40 G tonsyear bull Hence 03 years delay is worth 12 Gt CO2 ~ 200 Mt
CO2year
39
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
Cool and Standard Color-Matched Concrete Tiles
cool Courtesy American Rooftile Coatings
standard
bull Can increase solar reflectance by up to 05 bull Gain greatest for dark colors
∆R=037 ∆R=026 ∆R=023 ∆R=015 ∆R=029 ∆R=029
21
22
Increasing solar reflectance of fiberglass asphalt shingles prototypes
cooler ρ=028
ρ = solar reflectance
ρ=036
warmer ρ=023 ρ=027 ρ=028
ρ=037
23
Increasing solar reflectance of fiberglass asphalt shingles Elk Prestiquereg Cool Color Series
24
Increasing solar reflectance of metal roofing BASF Ultra-Coolreg metal roof coatings
numbers denote solar reflectances cooler (warmer)
Courtesy BASF
Industrial Coatings
25
Cool Metal Roofs
Increasing solar reflectance of clay tiles MCA Clay Tile cool colored tiles
26
Model Color Initial solar reflectance
Solar reflectance after 3 years
Weathered Green Blend
043 049
Natural Red 043 038
Brick Red 042 040
White Buff 068 056
Tobacco 043 041
27
Non-residential building energy and equipment savings15-year net present value of savings ($1000 ft2)
30-year net present value of savings ($1000 ft2) concrete tile roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 39 53 37 56 42 58 39 71 74 60 64 55 68 66 66 60
Energy 406 917 726 992 781 1593 1432 1822 1862 1390 1190 1109 1355 1477 1900 791 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
28
30-year net present value of savings ($1000 ft2) metal roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 41 57 41 61 47 57 48 83 88 65 71 60 73 72 71 65
Energy 495 1053 847 1128 919 1870 1692 2141 2181 1561 1330 1243 1507 1648 2093 918 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
29
Cool Roofs Standards bull Building standards for reflective roofs
- American Society of Heating and Air-conditioning Engineers (ASHRAE) New commercial and residential buildings
- Many state California Georgia Florida Hawaii hellip bull Air quality standards
- South Coast AQMD - SF Bay Area AQMD - EPArsquos SIP (State Implementation Plans)
30
White Roofs Programs in California
bull One Time CEC Incentive -- $20 Million frac34 at $015 to $020 per square foot
bull California utilities incentives bull 2001 to 2005-- credits white and cool colored
roofs bull 2005 requires cool flat roofs bull 2008 may require cool roofs for all buildings
31
Cool Roof Programs around the World
32
bull US bull Europe bull Asia bull Middle East
bull China bull India (Hyderabad
demos see graphs funded by USAID)
Cool Roofs to Save CO2
33
Cool Surfaces also Cool the Globe
bull Cool roof standards are designed to reduce ac demand save money and save emissions In Los Angeles they will eventually save ~$100000 per hour
bull Annual savings in the US = $1-2B ~ 7 M tons CO2
bull Annual savings in the world = $10-15B ~ 100 M tons CO2
bull But higher albedo surfaces (roofs and pavements) directly cool the world (001 K) quite independent of avoided CO2 So we discuss the effect of cool surfaces for tropical temperate cities
34
35
100 Largest Cities have 670 M People
0
1000
2000
3000
4000
5000
0 10 20 30 40
Population (M)
Are
a D
ensi
ty(m
2 per
son)
Mean = 560 m2p Med = 430 m2p
Tokyo
Mexico City New York City Mumbai Satildeo Paulo
Dense Urban Areas are 1 of Land
bull Area of the Earth = 511x1012 m2
bull Land Area (29) = 148x1012 m2 [1] bull Area of the 100 largest cities = 038x1012 m2 = 026
of Land Area for 670 M people bull Assuming 3B live in urban area urban areas =
[3000670] x 026 = 12 of land bull But smaller cities have lower population density
hence urban areas = 2 of land bull Dense developed urban areas only 1 of land [2]
36
Potentials to Increase Urban Albdeo is 01
bull Typical urban area is 25 roof and 35 paved surfaces
bull Roof albedo can increase by 025 for a net change of 025x025=0063
bull Paved surfaces albedo can increase by 015 for a net change of 035x015=0052
bull Net urban area albedo change at least 010
37
Effect of Increasing Urban Albedo by 01
bull Net Change in Global albedo = [CityLand]x[LandGlobe]x∆a = [2]x[1]x∆a = 001 x 029 x01 = 00003 [3]
bull The effect on global temperature frac34 Using three different calculations is about 001K
38
Carbon Equivalency bull Modelers estimate a warming of 2K in 60 years so
003Kyear bull Change of 01 in urban albedo will result in 001K a delay
of ~03 years in global warming bull Worldrsquos current rate of CO2 emissions =
25 G tonsyear (41 tonsyear per person) bull Worldrsquos rate of CO2 emissions averaged over next 60
years = 40 G tonsyear bull Hence 03 years delay is worth 12 Gt CO2 ~ 200 Mt
CO2year
39
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
22
Increasing solar reflectance of fiberglass asphalt shingles prototypes
cooler ρ=028
ρ = solar reflectance
ρ=036
warmer ρ=023 ρ=027 ρ=028
ρ=037
23
Increasing solar reflectance of fiberglass asphalt shingles Elk Prestiquereg Cool Color Series
24
Increasing solar reflectance of metal roofing BASF Ultra-Coolreg metal roof coatings
numbers denote solar reflectances cooler (warmer)
Courtesy BASF
Industrial Coatings
25
Cool Metal Roofs
Increasing solar reflectance of clay tiles MCA Clay Tile cool colored tiles
26
Model Color Initial solar reflectance
Solar reflectance after 3 years
Weathered Green Blend
043 049
Natural Red 043 038
Brick Red 042 040
White Buff 068 056
Tobacco 043 041
27
Non-residential building energy and equipment savings15-year net present value of savings ($1000 ft2)
30-year net present value of savings ($1000 ft2) concrete tile roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 39 53 37 56 42 58 39 71 74 60 64 55 68 66 66 60
Energy 406 917 726 992 781 1593 1432 1822 1862 1390 1190 1109 1355 1477 1900 791 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
28
30-year net present value of savings ($1000 ft2) metal roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 41 57 41 61 47 57 48 83 88 65 71 60 73 72 71 65
Energy 495 1053 847 1128 919 1870 1692 2141 2181 1561 1330 1243 1507 1648 2093 918 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
29
Cool Roofs Standards bull Building standards for reflective roofs
- American Society of Heating and Air-conditioning Engineers (ASHRAE) New commercial and residential buildings
- Many state California Georgia Florida Hawaii hellip bull Air quality standards
- South Coast AQMD - SF Bay Area AQMD - EPArsquos SIP (State Implementation Plans)
30
White Roofs Programs in California
bull One Time CEC Incentive -- $20 Million frac34 at $015 to $020 per square foot
bull California utilities incentives bull 2001 to 2005-- credits white and cool colored
roofs bull 2005 requires cool flat roofs bull 2008 may require cool roofs for all buildings
31
Cool Roof Programs around the World
32
bull US bull Europe bull Asia bull Middle East
bull China bull India (Hyderabad
demos see graphs funded by USAID)
Cool Roofs to Save CO2
33
Cool Surfaces also Cool the Globe
bull Cool roof standards are designed to reduce ac demand save money and save emissions In Los Angeles they will eventually save ~$100000 per hour
bull Annual savings in the US = $1-2B ~ 7 M tons CO2
bull Annual savings in the world = $10-15B ~ 100 M tons CO2
bull But higher albedo surfaces (roofs and pavements) directly cool the world (001 K) quite independent of avoided CO2 So we discuss the effect of cool surfaces for tropical temperate cities
34
35
100 Largest Cities have 670 M People
0
1000
2000
3000
4000
5000
0 10 20 30 40
Population (M)
Are
a D
ensi
ty(m
2 per
son)
Mean = 560 m2p Med = 430 m2p
Tokyo
Mexico City New York City Mumbai Satildeo Paulo
Dense Urban Areas are 1 of Land
bull Area of the Earth = 511x1012 m2
bull Land Area (29) = 148x1012 m2 [1] bull Area of the 100 largest cities = 038x1012 m2 = 026
of Land Area for 670 M people bull Assuming 3B live in urban area urban areas =
[3000670] x 026 = 12 of land bull But smaller cities have lower population density
hence urban areas = 2 of land bull Dense developed urban areas only 1 of land [2]
36
Potentials to Increase Urban Albdeo is 01
bull Typical urban area is 25 roof and 35 paved surfaces
bull Roof albedo can increase by 025 for a net change of 025x025=0063
bull Paved surfaces albedo can increase by 015 for a net change of 035x015=0052
bull Net urban area albedo change at least 010
37
Effect of Increasing Urban Albedo by 01
bull Net Change in Global albedo = [CityLand]x[LandGlobe]x∆a = [2]x[1]x∆a = 001 x 029 x01 = 00003 [3]
bull The effect on global temperature frac34 Using three different calculations is about 001K
38
Carbon Equivalency bull Modelers estimate a warming of 2K in 60 years so
003Kyear bull Change of 01 in urban albedo will result in 001K a delay
of ~03 years in global warming bull Worldrsquos current rate of CO2 emissions =
25 G tonsyear (41 tonsyear per person) bull Worldrsquos rate of CO2 emissions averaged over next 60
years = 40 G tonsyear bull Hence 03 years delay is worth 12 Gt CO2 ~ 200 Mt
CO2year
39
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
23
Increasing solar reflectance of fiberglass asphalt shingles Elk Prestiquereg Cool Color Series
24
Increasing solar reflectance of metal roofing BASF Ultra-Coolreg metal roof coatings
numbers denote solar reflectances cooler (warmer)
Courtesy BASF
Industrial Coatings
25
Cool Metal Roofs
Increasing solar reflectance of clay tiles MCA Clay Tile cool colored tiles
26
Model Color Initial solar reflectance
Solar reflectance after 3 years
Weathered Green Blend
043 049
Natural Red 043 038
Brick Red 042 040
White Buff 068 056
Tobacco 043 041
27
Non-residential building energy and equipment savings15-year net present value of savings ($1000 ft2)
30-year net present value of savings ($1000 ft2) concrete tile roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 39 53 37 56 42 58 39 71 74 60 64 55 68 66 66 60
Energy 406 917 726 992 781 1593 1432 1822 1862 1390 1190 1109 1355 1477 1900 791 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
28
30-year net present value of savings ($1000 ft2) metal roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 41 57 41 61 47 57 48 83 88 65 71 60 73 72 71 65
Energy 495 1053 847 1128 919 1870 1692 2141 2181 1561 1330 1243 1507 1648 2093 918 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
29
Cool Roofs Standards bull Building standards for reflective roofs
- American Society of Heating and Air-conditioning Engineers (ASHRAE) New commercial and residential buildings
- Many state California Georgia Florida Hawaii hellip bull Air quality standards
- South Coast AQMD - SF Bay Area AQMD - EPArsquos SIP (State Implementation Plans)
30
White Roofs Programs in California
bull One Time CEC Incentive -- $20 Million frac34 at $015 to $020 per square foot
bull California utilities incentives bull 2001 to 2005-- credits white and cool colored
roofs bull 2005 requires cool flat roofs bull 2008 may require cool roofs for all buildings
31
Cool Roof Programs around the World
32
bull US bull Europe bull Asia bull Middle East
bull China bull India (Hyderabad
demos see graphs funded by USAID)
Cool Roofs to Save CO2
33
Cool Surfaces also Cool the Globe
bull Cool roof standards are designed to reduce ac demand save money and save emissions In Los Angeles they will eventually save ~$100000 per hour
bull Annual savings in the US = $1-2B ~ 7 M tons CO2
bull Annual savings in the world = $10-15B ~ 100 M tons CO2
bull But higher albedo surfaces (roofs and pavements) directly cool the world (001 K) quite independent of avoided CO2 So we discuss the effect of cool surfaces for tropical temperate cities
34
35
100 Largest Cities have 670 M People
0
1000
2000
3000
4000
5000
0 10 20 30 40
Population (M)
Are
a D
ensi
ty(m
2 per
son)
Mean = 560 m2p Med = 430 m2p
Tokyo
Mexico City New York City Mumbai Satildeo Paulo
Dense Urban Areas are 1 of Land
bull Area of the Earth = 511x1012 m2
bull Land Area (29) = 148x1012 m2 [1] bull Area of the 100 largest cities = 038x1012 m2 = 026
of Land Area for 670 M people bull Assuming 3B live in urban area urban areas =
[3000670] x 026 = 12 of land bull But smaller cities have lower population density
hence urban areas = 2 of land bull Dense developed urban areas only 1 of land [2]
36
Potentials to Increase Urban Albdeo is 01
bull Typical urban area is 25 roof and 35 paved surfaces
bull Roof albedo can increase by 025 for a net change of 025x025=0063
bull Paved surfaces albedo can increase by 015 for a net change of 035x015=0052
bull Net urban area albedo change at least 010
37
Effect of Increasing Urban Albedo by 01
bull Net Change in Global albedo = [CityLand]x[LandGlobe]x∆a = [2]x[1]x∆a = 001 x 029 x01 = 00003 [3]
bull The effect on global temperature frac34 Using three different calculations is about 001K
38
Carbon Equivalency bull Modelers estimate a warming of 2K in 60 years so
003Kyear bull Change of 01 in urban albedo will result in 001K a delay
of ~03 years in global warming bull Worldrsquos current rate of CO2 emissions =
25 G tonsyear (41 tonsyear per person) bull Worldrsquos rate of CO2 emissions averaged over next 60
years = 40 G tonsyear bull Hence 03 years delay is worth 12 Gt CO2 ~ 200 Mt
CO2year
39
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
24
Increasing solar reflectance of metal roofing BASF Ultra-Coolreg metal roof coatings
numbers denote solar reflectances cooler (warmer)
Courtesy BASF
Industrial Coatings
25
Cool Metal Roofs
Increasing solar reflectance of clay tiles MCA Clay Tile cool colored tiles
26
Model Color Initial solar reflectance
Solar reflectance after 3 years
Weathered Green Blend
043 049
Natural Red 043 038
Brick Red 042 040
White Buff 068 056
Tobacco 043 041
27
Non-residential building energy and equipment savings15-year net present value of savings ($1000 ft2)
30-year net present value of savings ($1000 ft2) concrete tile roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 39 53 37 56 42 58 39 71 74 60 64 55 68 66 66 60
Energy 406 917 726 992 781 1593 1432 1822 1862 1390 1190 1109 1355 1477 1900 791 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
28
30-year net present value of savings ($1000 ft2) metal roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 41 57 41 61 47 57 48 83 88 65 71 60 73 72 71 65
Energy 495 1053 847 1128 919 1870 1692 2141 2181 1561 1330 1243 1507 1648 2093 918 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
29
Cool Roofs Standards bull Building standards for reflective roofs
- American Society of Heating and Air-conditioning Engineers (ASHRAE) New commercial and residential buildings
- Many state California Georgia Florida Hawaii hellip bull Air quality standards
- South Coast AQMD - SF Bay Area AQMD - EPArsquos SIP (State Implementation Plans)
30
White Roofs Programs in California
bull One Time CEC Incentive -- $20 Million frac34 at $015 to $020 per square foot
bull California utilities incentives bull 2001 to 2005-- credits white and cool colored
roofs bull 2005 requires cool flat roofs bull 2008 may require cool roofs for all buildings
31
Cool Roof Programs around the World
32
bull US bull Europe bull Asia bull Middle East
bull China bull India (Hyderabad
demos see graphs funded by USAID)
Cool Roofs to Save CO2
33
Cool Surfaces also Cool the Globe
bull Cool roof standards are designed to reduce ac demand save money and save emissions In Los Angeles they will eventually save ~$100000 per hour
bull Annual savings in the US = $1-2B ~ 7 M tons CO2
bull Annual savings in the world = $10-15B ~ 100 M tons CO2
bull But higher albedo surfaces (roofs and pavements) directly cool the world (001 K) quite independent of avoided CO2 So we discuss the effect of cool surfaces for tropical temperate cities
34
35
100 Largest Cities have 670 M People
0
1000
2000
3000
4000
5000
0 10 20 30 40
Population (M)
Are
a D
ensi
ty(m
2 per
son)
Mean = 560 m2p Med = 430 m2p
Tokyo
Mexico City New York City Mumbai Satildeo Paulo
Dense Urban Areas are 1 of Land
bull Area of the Earth = 511x1012 m2
bull Land Area (29) = 148x1012 m2 [1] bull Area of the 100 largest cities = 038x1012 m2 = 026
of Land Area for 670 M people bull Assuming 3B live in urban area urban areas =
[3000670] x 026 = 12 of land bull But smaller cities have lower population density
hence urban areas = 2 of land bull Dense developed urban areas only 1 of land [2]
36
Potentials to Increase Urban Albdeo is 01
bull Typical urban area is 25 roof and 35 paved surfaces
bull Roof albedo can increase by 025 for a net change of 025x025=0063
bull Paved surfaces albedo can increase by 015 for a net change of 035x015=0052
bull Net urban area albedo change at least 010
37
Effect of Increasing Urban Albedo by 01
bull Net Change in Global albedo = [CityLand]x[LandGlobe]x∆a = [2]x[1]x∆a = 001 x 029 x01 = 00003 [3]
bull The effect on global temperature frac34 Using three different calculations is about 001K
38
Carbon Equivalency bull Modelers estimate a warming of 2K in 60 years so
003Kyear bull Change of 01 in urban albedo will result in 001K a delay
of ~03 years in global warming bull Worldrsquos current rate of CO2 emissions =
25 G tonsyear (41 tonsyear per person) bull Worldrsquos rate of CO2 emissions averaged over next 60
years = 40 G tonsyear bull Hence 03 years delay is worth 12 Gt CO2 ~ 200 Mt
CO2year
39
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
25
Cool Metal Roofs
Increasing solar reflectance of clay tiles MCA Clay Tile cool colored tiles
26
Model Color Initial solar reflectance
Solar reflectance after 3 years
Weathered Green Blend
043 049
Natural Red 043 038
Brick Red 042 040
White Buff 068 056
Tobacco 043 041
27
Non-residential building energy and equipment savings15-year net present value of savings ($1000 ft2)
30-year net present value of savings ($1000 ft2) concrete tile roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 39 53 37 56 42 58 39 71 74 60 64 55 68 66 66 60
Energy 406 917 726 992 781 1593 1432 1822 1862 1390 1190 1109 1355 1477 1900 791 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
28
30-year net present value of savings ($1000 ft2) metal roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 41 57 41 61 47 57 48 83 88 65 71 60 73 72 71 65
Energy 495 1053 847 1128 919 1870 1692 2141 2181 1561 1330 1243 1507 1648 2093 918 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
29
Cool Roofs Standards bull Building standards for reflective roofs
- American Society of Heating and Air-conditioning Engineers (ASHRAE) New commercial and residential buildings
- Many state California Georgia Florida Hawaii hellip bull Air quality standards
- South Coast AQMD - SF Bay Area AQMD - EPArsquos SIP (State Implementation Plans)
30
White Roofs Programs in California
bull One Time CEC Incentive -- $20 Million frac34 at $015 to $020 per square foot
bull California utilities incentives bull 2001 to 2005-- credits white and cool colored
roofs bull 2005 requires cool flat roofs bull 2008 may require cool roofs for all buildings
31
Cool Roof Programs around the World
32
bull US bull Europe bull Asia bull Middle East
bull China bull India (Hyderabad
demos see graphs funded by USAID)
Cool Roofs to Save CO2
33
Cool Surfaces also Cool the Globe
bull Cool roof standards are designed to reduce ac demand save money and save emissions In Los Angeles they will eventually save ~$100000 per hour
bull Annual savings in the US = $1-2B ~ 7 M tons CO2
bull Annual savings in the world = $10-15B ~ 100 M tons CO2
bull But higher albedo surfaces (roofs and pavements) directly cool the world (001 K) quite independent of avoided CO2 So we discuss the effect of cool surfaces for tropical temperate cities
34
35
100 Largest Cities have 670 M People
0
1000
2000
3000
4000
5000
0 10 20 30 40
Population (M)
Are
a D
ensi
ty(m
2 per
son)
Mean = 560 m2p Med = 430 m2p
Tokyo
Mexico City New York City Mumbai Satildeo Paulo
Dense Urban Areas are 1 of Land
bull Area of the Earth = 511x1012 m2
bull Land Area (29) = 148x1012 m2 [1] bull Area of the 100 largest cities = 038x1012 m2 = 026
of Land Area for 670 M people bull Assuming 3B live in urban area urban areas =
[3000670] x 026 = 12 of land bull But smaller cities have lower population density
hence urban areas = 2 of land bull Dense developed urban areas only 1 of land [2]
36
Potentials to Increase Urban Albdeo is 01
bull Typical urban area is 25 roof and 35 paved surfaces
bull Roof albedo can increase by 025 for a net change of 025x025=0063
bull Paved surfaces albedo can increase by 015 for a net change of 035x015=0052
bull Net urban area albedo change at least 010
37
Effect of Increasing Urban Albedo by 01
bull Net Change in Global albedo = [CityLand]x[LandGlobe]x∆a = [2]x[1]x∆a = 001 x 029 x01 = 00003 [3]
bull The effect on global temperature frac34 Using three different calculations is about 001K
38
Carbon Equivalency bull Modelers estimate a warming of 2K in 60 years so
003Kyear bull Change of 01 in urban albedo will result in 001K a delay
of ~03 years in global warming bull Worldrsquos current rate of CO2 emissions =
25 G tonsyear (41 tonsyear per person) bull Worldrsquos rate of CO2 emissions averaged over next 60
years = 40 G tonsyear bull Hence 03 years delay is worth 12 Gt CO2 ~ 200 Mt
CO2year
39
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
Increasing solar reflectance of clay tiles MCA Clay Tile cool colored tiles
26
Model Color Initial solar reflectance
Solar reflectance after 3 years
Weathered Green Blend
043 049
Natural Red 043 038
Brick Red 042 040
White Buff 068 056
Tobacco 043 041
27
Non-residential building energy and equipment savings15-year net present value of savings ($1000 ft2)
30-year net present value of savings ($1000 ft2) concrete tile roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 39 53 37 56 42 58 39 71 74 60 64 55 68 66 66 60
Energy 406 917 726 992 781 1593 1432 1822 1862 1390 1190 1109 1355 1477 1900 791 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
28
30-year net present value of savings ($1000 ft2) metal roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 41 57 41 61 47 57 48 83 88 65 71 60 73 72 71 65
Energy 495 1053 847 1128 919 1870 1692 2141 2181 1561 1330 1243 1507 1648 2093 918 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
29
Cool Roofs Standards bull Building standards for reflective roofs
- American Society of Heating and Air-conditioning Engineers (ASHRAE) New commercial and residential buildings
- Many state California Georgia Florida Hawaii hellip bull Air quality standards
- South Coast AQMD - SF Bay Area AQMD - EPArsquos SIP (State Implementation Plans)
30
White Roofs Programs in California
bull One Time CEC Incentive -- $20 Million frac34 at $015 to $020 per square foot
bull California utilities incentives bull 2001 to 2005-- credits white and cool colored
roofs bull 2005 requires cool flat roofs bull 2008 may require cool roofs for all buildings
31
Cool Roof Programs around the World
32
bull US bull Europe bull Asia bull Middle East
bull China bull India (Hyderabad
demos see graphs funded by USAID)
Cool Roofs to Save CO2
33
Cool Surfaces also Cool the Globe
bull Cool roof standards are designed to reduce ac demand save money and save emissions In Los Angeles they will eventually save ~$100000 per hour
bull Annual savings in the US = $1-2B ~ 7 M tons CO2
bull Annual savings in the world = $10-15B ~ 100 M tons CO2
bull But higher albedo surfaces (roofs and pavements) directly cool the world (001 K) quite independent of avoided CO2 So we discuss the effect of cool surfaces for tropical temperate cities
34
35
100 Largest Cities have 670 M People
0
1000
2000
3000
4000
5000
0 10 20 30 40
Population (M)
Are
a D
ensi
ty(m
2 per
son)
Mean = 560 m2p Med = 430 m2p
Tokyo
Mexico City New York City Mumbai Satildeo Paulo
Dense Urban Areas are 1 of Land
bull Area of the Earth = 511x1012 m2
bull Land Area (29) = 148x1012 m2 [1] bull Area of the 100 largest cities = 038x1012 m2 = 026
of Land Area for 670 M people bull Assuming 3B live in urban area urban areas =
[3000670] x 026 = 12 of land bull But smaller cities have lower population density
hence urban areas = 2 of land bull Dense developed urban areas only 1 of land [2]
36
Potentials to Increase Urban Albdeo is 01
bull Typical urban area is 25 roof and 35 paved surfaces
bull Roof albedo can increase by 025 for a net change of 025x025=0063
bull Paved surfaces albedo can increase by 015 for a net change of 035x015=0052
bull Net urban area albedo change at least 010
37
Effect of Increasing Urban Albedo by 01
bull Net Change in Global albedo = [CityLand]x[LandGlobe]x∆a = [2]x[1]x∆a = 001 x 029 x01 = 00003 [3]
bull The effect on global temperature frac34 Using three different calculations is about 001K
38
Carbon Equivalency bull Modelers estimate a warming of 2K in 60 years so
003Kyear bull Change of 01 in urban albedo will result in 001K a delay
of ~03 years in global warming bull Worldrsquos current rate of CO2 emissions =
25 G tonsyear (41 tonsyear per person) bull Worldrsquos rate of CO2 emissions averaged over next 60
years = 40 G tonsyear bull Hence 03 years delay is worth 12 Gt CO2 ~ 200 Mt
CO2year
39
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
27
Non-residential building energy and equipment savings15-year net present value of savings ($1000 ft2)
30-year net present value of savings ($1000 ft2) concrete tile roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 39 53 37 56 42 58 39 71 74 60 64 55 68 66 66 60
Energy 406 917 726 992 781 1593 1432 1822 1862 1390 1190 1109 1355 1477 1900 791 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
28
30-year net present value of savings ($1000 ft2) metal roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 41 57 41 61 47 57 48 83 88 65 71 60 73 72 71 65
Energy 495 1053 847 1128 919 1870 1692 2141 2181 1561 1330 1243 1507 1648 2093 918 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
29
Cool Roofs Standards bull Building standards for reflective roofs
- American Society of Heating and Air-conditioning Engineers (ASHRAE) New commercial and residential buildings
- Many state California Georgia Florida Hawaii hellip bull Air quality standards
- South Coast AQMD - SF Bay Area AQMD - EPArsquos SIP (State Implementation Plans)
30
White Roofs Programs in California
bull One Time CEC Incentive -- $20 Million frac34 at $015 to $020 per square foot
bull California utilities incentives bull 2001 to 2005-- credits white and cool colored
roofs bull 2005 requires cool flat roofs bull 2008 may require cool roofs for all buildings
31
Cool Roof Programs around the World
32
bull US bull Europe bull Asia bull Middle East
bull China bull India (Hyderabad
demos see graphs funded by USAID)
Cool Roofs to Save CO2
33
Cool Surfaces also Cool the Globe
bull Cool roof standards are designed to reduce ac demand save money and save emissions In Los Angeles they will eventually save ~$100000 per hour
bull Annual savings in the US = $1-2B ~ 7 M tons CO2
bull Annual savings in the world = $10-15B ~ 100 M tons CO2
bull But higher albedo surfaces (roofs and pavements) directly cool the world (001 K) quite independent of avoided CO2 So we discuss the effect of cool surfaces for tropical temperate cities
34
35
100 Largest Cities have 670 M People
0
1000
2000
3000
4000
5000
0 10 20 30 40
Population (M)
Are
a D
ensi
ty(m
2 per
son)
Mean = 560 m2p Med = 430 m2p
Tokyo
Mexico City New York City Mumbai Satildeo Paulo
Dense Urban Areas are 1 of Land
bull Area of the Earth = 511x1012 m2
bull Land Area (29) = 148x1012 m2 [1] bull Area of the 100 largest cities = 038x1012 m2 = 026
of Land Area for 670 M people bull Assuming 3B live in urban area urban areas =
[3000670] x 026 = 12 of land bull But smaller cities have lower population density
hence urban areas = 2 of land bull Dense developed urban areas only 1 of land [2]
36
Potentials to Increase Urban Albdeo is 01
bull Typical urban area is 25 roof and 35 paved surfaces
bull Roof albedo can increase by 025 for a net change of 025x025=0063
bull Paved surfaces albedo can increase by 015 for a net change of 035x015=0052
bull Net urban area albedo change at least 010
37
Effect of Increasing Urban Albedo by 01
bull Net Change in Global albedo = [CityLand]x[LandGlobe]x∆a = [2]x[1]x∆a = 001 x 029 x01 = 00003 [3]
bull The effect on global temperature frac34 Using three different calculations is about 001K
38
Carbon Equivalency bull Modelers estimate a warming of 2K in 60 years so
003Kyear bull Change of 01 in urban albedo will result in 001K a delay
of ~03 years in global warming bull Worldrsquos current rate of CO2 emissions =
25 G tonsyear (41 tonsyear per person) bull Worldrsquos rate of CO2 emissions averaged over next 60
years = 40 G tonsyear bull Hence 03 years delay is worth 12 Gt CO2 ~ 200 Mt
CO2year
39
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
30-year net present value of savings ($1000 ft2) concrete tile roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 39 53 37 56 42 58 39 71 74 60 64 55 68 66 66 60
Energy 406 917 726 992 781 1593 1432 1822 1862 1390 1190 1109 1355 1477 1900 791 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
28
30-year net present value of savings ($1000 ft2) metal roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 41 57 41 61 47 57 48 83 88 65 71 60 73 72 71 65
Energy 495 1053 847 1128 919 1870 1692 2141 2181 1561 1330 1243 1507 1648 2093 918 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
29
Cool Roofs Standards bull Building standards for reflective roofs
- American Society of Heating and Air-conditioning Engineers (ASHRAE) New commercial and residential buildings
- Many state California Georgia Florida Hawaii hellip bull Air quality standards
- South Coast AQMD - SF Bay Area AQMD - EPArsquos SIP (State Implementation Plans)
30
White Roofs Programs in California
bull One Time CEC Incentive -- $20 Million frac34 at $015 to $020 per square foot
bull California utilities incentives bull 2001 to 2005-- credits white and cool colored
roofs bull 2005 requires cool flat roofs bull 2008 may require cool roofs for all buildings
31
Cool Roof Programs around the World
32
bull US bull Europe bull Asia bull Middle East
bull China bull India (Hyderabad
demos see graphs funded by USAID)
Cool Roofs to Save CO2
33
Cool Surfaces also Cool the Globe
bull Cool roof standards are designed to reduce ac demand save money and save emissions In Los Angeles they will eventually save ~$100000 per hour
bull Annual savings in the US = $1-2B ~ 7 M tons CO2
bull Annual savings in the world = $10-15B ~ 100 M tons CO2
bull But higher albedo surfaces (roofs and pavements) directly cool the world (001 K) quite independent of avoided CO2 So we discuss the effect of cool surfaces for tropical temperate cities
34
35
100 Largest Cities have 670 M People
0
1000
2000
3000
4000
5000
0 10 20 30 40
Population (M)
Are
a D
ensi
ty(m
2 per
son)
Mean = 560 m2p Med = 430 m2p
Tokyo
Mexico City New York City Mumbai Satildeo Paulo
Dense Urban Areas are 1 of Land
bull Area of the Earth = 511x1012 m2
bull Land Area (29) = 148x1012 m2 [1] bull Area of the 100 largest cities = 038x1012 m2 = 026
of Land Area for 670 M people bull Assuming 3B live in urban area urban areas =
[3000670] x 026 = 12 of land bull But smaller cities have lower population density
hence urban areas = 2 of land bull Dense developed urban areas only 1 of land [2]
36
Potentials to Increase Urban Albdeo is 01
bull Typical urban area is 25 roof and 35 paved surfaces
bull Roof albedo can increase by 025 for a net change of 025x025=0063
bull Paved surfaces albedo can increase by 015 for a net change of 035x015=0052
bull Net urban area albedo change at least 010
37
Effect of Increasing Urban Albedo by 01
bull Net Change in Global albedo = [CityLand]x[LandGlobe]x∆a = [2]x[1]x∆a = 001 x 029 x01 = 00003 [3]
bull The effect on global temperature frac34 Using three different calculations is about 001K
38
Carbon Equivalency bull Modelers estimate a warming of 2K in 60 years so
003Kyear bull Change of 01 in urban albedo will result in 001K a delay
of ~03 years in global warming bull Worldrsquos current rate of CO2 emissions =
25 G tonsyear (41 tonsyear per person) bull Worldrsquos rate of CO2 emissions averaged over next 60
years = 40 G tonsyear bull Hence 03 years delay is worth 12 Gt CO2 ~ 200 Mt
CO2year
39
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
30-year net present value of savings ($1000 ft2) metal roofs
0
500
1000
1500
2000
2500
3000
California Climate Zone
Equip 41 57 41 61 47 57 48 83 88 65 71 60 73 72 71 65
Energy 495 1053 847 1128 919 1870 1692 2141 2181 1561 1330 1243 1507 1648 2093 918 $010ft2 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Tota
l Sav
ings
[Equ
ipm
ent +
30-
Year
NPV
Ene
rgy]
($1
000
ft2)
29
Cool Roofs Standards bull Building standards for reflective roofs
- American Society of Heating and Air-conditioning Engineers (ASHRAE) New commercial and residential buildings
- Many state California Georgia Florida Hawaii hellip bull Air quality standards
- South Coast AQMD - SF Bay Area AQMD - EPArsquos SIP (State Implementation Plans)
30
White Roofs Programs in California
bull One Time CEC Incentive -- $20 Million frac34 at $015 to $020 per square foot
bull California utilities incentives bull 2001 to 2005-- credits white and cool colored
roofs bull 2005 requires cool flat roofs bull 2008 may require cool roofs for all buildings
31
Cool Roof Programs around the World
32
bull US bull Europe bull Asia bull Middle East
bull China bull India (Hyderabad
demos see graphs funded by USAID)
Cool Roofs to Save CO2
33
Cool Surfaces also Cool the Globe
bull Cool roof standards are designed to reduce ac demand save money and save emissions In Los Angeles they will eventually save ~$100000 per hour
bull Annual savings in the US = $1-2B ~ 7 M tons CO2
bull Annual savings in the world = $10-15B ~ 100 M tons CO2
bull But higher albedo surfaces (roofs and pavements) directly cool the world (001 K) quite independent of avoided CO2 So we discuss the effect of cool surfaces for tropical temperate cities
34
35
100 Largest Cities have 670 M People
0
1000
2000
3000
4000
5000
0 10 20 30 40
Population (M)
Are
a D
ensi
ty(m
2 per
son)
Mean = 560 m2p Med = 430 m2p
Tokyo
Mexico City New York City Mumbai Satildeo Paulo
Dense Urban Areas are 1 of Land
bull Area of the Earth = 511x1012 m2
bull Land Area (29) = 148x1012 m2 [1] bull Area of the 100 largest cities = 038x1012 m2 = 026
of Land Area for 670 M people bull Assuming 3B live in urban area urban areas =
[3000670] x 026 = 12 of land bull But smaller cities have lower population density
hence urban areas = 2 of land bull Dense developed urban areas only 1 of land [2]
36
Potentials to Increase Urban Albdeo is 01
bull Typical urban area is 25 roof and 35 paved surfaces
bull Roof albedo can increase by 025 for a net change of 025x025=0063
bull Paved surfaces albedo can increase by 015 for a net change of 035x015=0052
bull Net urban area albedo change at least 010
37
Effect of Increasing Urban Albedo by 01
bull Net Change in Global albedo = [CityLand]x[LandGlobe]x∆a = [2]x[1]x∆a = 001 x 029 x01 = 00003 [3]
bull The effect on global temperature frac34 Using three different calculations is about 001K
38
Carbon Equivalency bull Modelers estimate a warming of 2K in 60 years so
003Kyear bull Change of 01 in urban albedo will result in 001K a delay
of ~03 years in global warming bull Worldrsquos current rate of CO2 emissions =
25 G tonsyear (41 tonsyear per person) bull Worldrsquos rate of CO2 emissions averaged over next 60
years = 40 G tonsyear bull Hence 03 years delay is worth 12 Gt CO2 ~ 200 Mt
CO2year
39
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
Cool Roofs Standards bull Building standards for reflective roofs
- American Society of Heating and Air-conditioning Engineers (ASHRAE) New commercial and residential buildings
- Many state California Georgia Florida Hawaii hellip bull Air quality standards
- South Coast AQMD - SF Bay Area AQMD - EPArsquos SIP (State Implementation Plans)
30
White Roofs Programs in California
bull One Time CEC Incentive -- $20 Million frac34 at $015 to $020 per square foot
bull California utilities incentives bull 2001 to 2005-- credits white and cool colored
roofs bull 2005 requires cool flat roofs bull 2008 may require cool roofs for all buildings
31
Cool Roof Programs around the World
32
bull US bull Europe bull Asia bull Middle East
bull China bull India (Hyderabad
demos see graphs funded by USAID)
Cool Roofs to Save CO2
33
Cool Surfaces also Cool the Globe
bull Cool roof standards are designed to reduce ac demand save money and save emissions In Los Angeles they will eventually save ~$100000 per hour
bull Annual savings in the US = $1-2B ~ 7 M tons CO2
bull Annual savings in the world = $10-15B ~ 100 M tons CO2
bull But higher albedo surfaces (roofs and pavements) directly cool the world (001 K) quite independent of avoided CO2 So we discuss the effect of cool surfaces for tropical temperate cities
34
35
100 Largest Cities have 670 M People
0
1000
2000
3000
4000
5000
0 10 20 30 40
Population (M)
Are
a D
ensi
ty(m
2 per
son)
Mean = 560 m2p Med = 430 m2p
Tokyo
Mexico City New York City Mumbai Satildeo Paulo
Dense Urban Areas are 1 of Land
bull Area of the Earth = 511x1012 m2
bull Land Area (29) = 148x1012 m2 [1] bull Area of the 100 largest cities = 038x1012 m2 = 026
of Land Area for 670 M people bull Assuming 3B live in urban area urban areas =
[3000670] x 026 = 12 of land bull But smaller cities have lower population density
hence urban areas = 2 of land bull Dense developed urban areas only 1 of land [2]
36
Potentials to Increase Urban Albdeo is 01
bull Typical urban area is 25 roof and 35 paved surfaces
bull Roof albedo can increase by 025 for a net change of 025x025=0063
bull Paved surfaces albedo can increase by 015 for a net change of 035x015=0052
bull Net urban area albedo change at least 010
37
Effect of Increasing Urban Albedo by 01
bull Net Change in Global albedo = [CityLand]x[LandGlobe]x∆a = [2]x[1]x∆a = 001 x 029 x01 = 00003 [3]
bull The effect on global temperature frac34 Using three different calculations is about 001K
38
Carbon Equivalency bull Modelers estimate a warming of 2K in 60 years so
003Kyear bull Change of 01 in urban albedo will result in 001K a delay
of ~03 years in global warming bull Worldrsquos current rate of CO2 emissions =
25 G tonsyear (41 tonsyear per person) bull Worldrsquos rate of CO2 emissions averaged over next 60
years = 40 G tonsyear bull Hence 03 years delay is worth 12 Gt CO2 ~ 200 Mt
CO2year
39
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
White Roofs Programs in California
bull One Time CEC Incentive -- $20 Million frac34 at $015 to $020 per square foot
bull California utilities incentives bull 2001 to 2005-- credits white and cool colored
roofs bull 2005 requires cool flat roofs bull 2008 may require cool roofs for all buildings
31
Cool Roof Programs around the World
32
bull US bull Europe bull Asia bull Middle East
bull China bull India (Hyderabad
demos see graphs funded by USAID)
Cool Roofs to Save CO2
33
Cool Surfaces also Cool the Globe
bull Cool roof standards are designed to reduce ac demand save money and save emissions In Los Angeles they will eventually save ~$100000 per hour
bull Annual savings in the US = $1-2B ~ 7 M tons CO2
bull Annual savings in the world = $10-15B ~ 100 M tons CO2
bull But higher albedo surfaces (roofs and pavements) directly cool the world (001 K) quite independent of avoided CO2 So we discuss the effect of cool surfaces for tropical temperate cities
34
35
100 Largest Cities have 670 M People
0
1000
2000
3000
4000
5000
0 10 20 30 40
Population (M)
Are
a D
ensi
ty(m
2 per
son)
Mean = 560 m2p Med = 430 m2p
Tokyo
Mexico City New York City Mumbai Satildeo Paulo
Dense Urban Areas are 1 of Land
bull Area of the Earth = 511x1012 m2
bull Land Area (29) = 148x1012 m2 [1] bull Area of the 100 largest cities = 038x1012 m2 = 026
of Land Area for 670 M people bull Assuming 3B live in urban area urban areas =
[3000670] x 026 = 12 of land bull But smaller cities have lower population density
hence urban areas = 2 of land bull Dense developed urban areas only 1 of land [2]
36
Potentials to Increase Urban Albdeo is 01
bull Typical urban area is 25 roof and 35 paved surfaces
bull Roof albedo can increase by 025 for a net change of 025x025=0063
bull Paved surfaces albedo can increase by 015 for a net change of 035x015=0052
bull Net urban area albedo change at least 010
37
Effect of Increasing Urban Albedo by 01
bull Net Change in Global albedo = [CityLand]x[LandGlobe]x∆a = [2]x[1]x∆a = 001 x 029 x01 = 00003 [3]
bull The effect on global temperature frac34 Using three different calculations is about 001K
38
Carbon Equivalency bull Modelers estimate a warming of 2K in 60 years so
003Kyear bull Change of 01 in urban albedo will result in 001K a delay
of ~03 years in global warming bull Worldrsquos current rate of CO2 emissions =
25 G tonsyear (41 tonsyear per person) bull Worldrsquos rate of CO2 emissions averaged over next 60
years = 40 G tonsyear bull Hence 03 years delay is worth 12 Gt CO2 ~ 200 Mt
CO2year
39
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
Cool Roof Programs around the World
32
bull US bull Europe bull Asia bull Middle East
bull China bull India (Hyderabad
demos see graphs funded by USAID)
Cool Roofs to Save CO2
33
Cool Surfaces also Cool the Globe
bull Cool roof standards are designed to reduce ac demand save money and save emissions In Los Angeles they will eventually save ~$100000 per hour
bull Annual savings in the US = $1-2B ~ 7 M tons CO2
bull Annual savings in the world = $10-15B ~ 100 M tons CO2
bull But higher albedo surfaces (roofs and pavements) directly cool the world (001 K) quite independent of avoided CO2 So we discuss the effect of cool surfaces for tropical temperate cities
34
35
100 Largest Cities have 670 M People
0
1000
2000
3000
4000
5000
0 10 20 30 40
Population (M)
Are
a D
ensi
ty(m
2 per
son)
Mean = 560 m2p Med = 430 m2p
Tokyo
Mexico City New York City Mumbai Satildeo Paulo
Dense Urban Areas are 1 of Land
bull Area of the Earth = 511x1012 m2
bull Land Area (29) = 148x1012 m2 [1] bull Area of the 100 largest cities = 038x1012 m2 = 026
of Land Area for 670 M people bull Assuming 3B live in urban area urban areas =
[3000670] x 026 = 12 of land bull But smaller cities have lower population density
hence urban areas = 2 of land bull Dense developed urban areas only 1 of land [2]
36
Potentials to Increase Urban Albdeo is 01
bull Typical urban area is 25 roof and 35 paved surfaces
bull Roof albedo can increase by 025 for a net change of 025x025=0063
bull Paved surfaces albedo can increase by 015 for a net change of 035x015=0052
bull Net urban area albedo change at least 010
37
Effect of Increasing Urban Albedo by 01
bull Net Change in Global albedo = [CityLand]x[LandGlobe]x∆a = [2]x[1]x∆a = 001 x 029 x01 = 00003 [3]
bull The effect on global temperature frac34 Using three different calculations is about 001K
38
Carbon Equivalency bull Modelers estimate a warming of 2K in 60 years so
003Kyear bull Change of 01 in urban albedo will result in 001K a delay
of ~03 years in global warming bull Worldrsquos current rate of CO2 emissions =
25 G tonsyear (41 tonsyear per person) bull Worldrsquos rate of CO2 emissions averaged over next 60
years = 40 G tonsyear bull Hence 03 years delay is worth 12 Gt CO2 ~ 200 Mt
CO2year
39
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
Cool Roofs to Save CO2
33
Cool Surfaces also Cool the Globe
bull Cool roof standards are designed to reduce ac demand save money and save emissions In Los Angeles they will eventually save ~$100000 per hour
bull Annual savings in the US = $1-2B ~ 7 M tons CO2
bull Annual savings in the world = $10-15B ~ 100 M tons CO2
bull But higher albedo surfaces (roofs and pavements) directly cool the world (001 K) quite independent of avoided CO2 So we discuss the effect of cool surfaces for tropical temperate cities
34
35
100 Largest Cities have 670 M People
0
1000
2000
3000
4000
5000
0 10 20 30 40
Population (M)
Are
a D
ensi
ty(m
2 per
son)
Mean = 560 m2p Med = 430 m2p
Tokyo
Mexico City New York City Mumbai Satildeo Paulo
Dense Urban Areas are 1 of Land
bull Area of the Earth = 511x1012 m2
bull Land Area (29) = 148x1012 m2 [1] bull Area of the 100 largest cities = 038x1012 m2 = 026
of Land Area for 670 M people bull Assuming 3B live in urban area urban areas =
[3000670] x 026 = 12 of land bull But smaller cities have lower population density
hence urban areas = 2 of land bull Dense developed urban areas only 1 of land [2]
36
Potentials to Increase Urban Albdeo is 01
bull Typical urban area is 25 roof and 35 paved surfaces
bull Roof albedo can increase by 025 for a net change of 025x025=0063
bull Paved surfaces albedo can increase by 015 for a net change of 035x015=0052
bull Net urban area albedo change at least 010
37
Effect of Increasing Urban Albedo by 01
bull Net Change in Global albedo = [CityLand]x[LandGlobe]x∆a = [2]x[1]x∆a = 001 x 029 x01 = 00003 [3]
bull The effect on global temperature frac34 Using three different calculations is about 001K
38
Carbon Equivalency bull Modelers estimate a warming of 2K in 60 years so
003Kyear bull Change of 01 in urban albedo will result in 001K a delay
of ~03 years in global warming bull Worldrsquos current rate of CO2 emissions =
25 G tonsyear (41 tonsyear per person) bull Worldrsquos rate of CO2 emissions averaged over next 60
years = 40 G tonsyear bull Hence 03 years delay is worth 12 Gt CO2 ~ 200 Mt
CO2year
39
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
Cool Surfaces also Cool the Globe
bull Cool roof standards are designed to reduce ac demand save money and save emissions In Los Angeles they will eventually save ~$100000 per hour
bull Annual savings in the US = $1-2B ~ 7 M tons CO2
bull Annual savings in the world = $10-15B ~ 100 M tons CO2
bull But higher albedo surfaces (roofs and pavements) directly cool the world (001 K) quite independent of avoided CO2 So we discuss the effect of cool surfaces for tropical temperate cities
34
35
100 Largest Cities have 670 M People
0
1000
2000
3000
4000
5000
0 10 20 30 40
Population (M)
Are
a D
ensi
ty(m
2 per
son)
Mean = 560 m2p Med = 430 m2p
Tokyo
Mexico City New York City Mumbai Satildeo Paulo
Dense Urban Areas are 1 of Land
bull Area of the Earth = 511x1012 m2
bull Land Area (29) = 148x1012 m2 [1] bull Area of the 100 largest cities = 038x1012 m2 = 026
of Land Area for 670 M people bull Assuming 3B live in urban area urban areas =
[3000670] x 026 = 12 of land bull But smaller cities have lower population density
hence urban areas = 2 of land bull Dense developed urban areas only 1 of land [2]
36
Potentials to Increase Urban Albdeo is 01
bull Typical urban area is 25 roof and 35 paved surfaces
bull Roof albedo can increase by 025 for a net change of 025x025=0063
bull Paved surfaces albedo can increase by 015 for a net change of 035x015=0052
bull Net urban area albedo change at least 010
37
Effect of Increasing Urban Albedo by 01
bull Net Change in Global albedo = [CityLand]x[LandGlobe]x∆a = [2]x[1]x∆a = 001 x 029 x01 = 00003 [3]
bull The effect on global temperature frac34 Using three different calculations is about 001K
38
Carbon Equivalency bull Modelers estimate a warming of 2K in 60 years so
003Kyear bull Change of 01 in urban albedo will result in 001K a delay
of ~03 years in global warming bull Worldrsquos current rate of CO2 emissions =
25 G tonsyear (41 tonsyear per person) bull Worldrsquos rate of CO2 emissions averaged over next 60
years = 40 G tonsyear bull Hence 03 years delay is worth 12 Gt CO2 ~ 200 Mt
CO2year
39
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
35
100 Largest Cities have 670 M People
0
1000
2000
3000
4000
5000
0 10 20 30 40
Population (M)
Are
a D
ensi
ty(m
2 per
son)
Mean = 560 m2p Med = 430 m2p
Tokyo
Mexico City New York City Mumbai Satildeo Paulo
Dense Urban Areas are 1 of Land
bull Area of the Earth = 511x1012 m2
bull Land Area (29) = 148x1012 m2 [1] bull Area of the 100 largest cities = 038x1012 m2 = 026
of Land Area for 670 M people bull Assuming 3B live in urban area urban areas =
[3000670] x 026 = 12 of land bull But smaller cities have lower population density
hence urban areas = 2 of land bull Dense developed urban areas only 1 of land [2]
36
Potentials to Increase Urban Albdeo is 01
bull Typical urban area is 25 roof and 35 paved surfaces
bull Roof albedo can increase by 025 for a net change of 025x025=0063
bull Paved surfaces albedo can increase by 015 for a net change of 035x015=0052
bull Net urban area albedo change at least 010
37
Effect of Increasing Urban Albedo by 01
bull Net Change in Global albedo = [CityLand]x[LandGlobe]x∆a = [2]x[1]x∆a = 001 x 029 x01 = 00003 [3]
bull The effect on global temperature frac34 Using three different calculations is about 001K
38
Carbon Equivalency bull Modelers estimate a warming of 2K in 60 years so
003Kyear bull Change of 01 in urban albedo will result in 001K a delay
of ~03 years in global warming bull Worldrsquos current rate of CO2 emissions =
25 G tonsyear (41 tonsyear per person) bull Worldrsquos rate of CO2 emissions averaged over next 60
years = 40 G tonsyear bull Hence 03 years delay is worth 12 Gt CO2 ~ 200 Mt
CO2year
39
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
Dense Urban Areas are 1 of Land
bull Area of the Earth = 511x1012 m2
bull Land Area (29) = 148x1012 m2 [1] bull Area of the 100 largest cities = 038x1012 m2 = 026
of Land Area for 670 M people bull Assuming 3B live in urban area urban areas =
[3000670] x 026 = 12 of land bull But smaller cities have lower population density
hence urban areas = 2 of land bull Dense developed urban areas only 1 of land [2]
36
Potentials to Increase Urban Albdeo is 01
bull Typical urban area is 25 roof and 35 paved surfaces
bull Roof albedo can increase by 025 for a net change of 025x025=0063
bull Paved surfaces albedo can increase by 015 for a net change of 035x015=0052
bull Net urban area albedo change at least 010
37
Effect of Increasing Urban Albedo by 01
bull Net Change in Global albedo = [CityLand]x[LandGlobe]x∆a = [2]x[1]x∆a = 001 x 029 x01 = 00003 [3]
bull The effect on global temperature frac34 Using three different calculations is about 001K
38
Carbon Equivalency bull Modelers estimate a warming of 2K in 60 years so
003Kyear bull Change of 01 in urban albedo will result in 001K a delay
of ~03 years in global warming bull Worldrsquos current rate of CO2 emissions =
25 G tonsyear (41 tonsyear per person) bull Worldrsquos rate of CO2 emissions averaged over next 60
years = 40 G tonsyear bull Hence 03 years delay is worth 12 Gt CO2 ~ 200 Mt
CO2year
39
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
Potentials to Increase Urban Albdeo is 01
bull Typical urban area is 25 roof and 35 paved surfaces
bull Roof albedo can increase by 025 for a net change of 025x025=0063
bull Paved surfaces albedo can increase by 015 for a net change of 035x015=0052
bull Net urban area albedo change at least 010
37
Effect of Increasing Urban Albedo by 01
bull Net Change in Global albedo = [CityLand]x[LandGlobe]x∆a = [2]x[1]x∆a = 001 x 029 x01 = 00003 [3]
bull The effect on global temperature frac34 Using three different calculations is about 001K
38
Carbon Equivalency bull Modelers estimate a warming of 2K in 60 years so
003Kyear bull Change of 01 in urban albedo will result in 001K a delay
of ~03 years in global warming bull Worldrsquos current rate of CO2 emissions =
25 G tonsyear (41 tonsyear per person) bull Worldrsquos rate of CO2 emissions averaged over next 60
years = 40 G tonsyear bull Hence 03 years delay is worth 12 Gt CO2 ~ 200 Mt
CO2year
39
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
Effect of Increasing Urban Albedo by 01
bull Net Change in Global albedo = [CityLand]x[LandGlobe]x∆a = [2]x[1]x∆a = 001 x 029 x01 = 00003 [3]
bull The effect on global temperature frac34 Using three different calculations is about 001K
38
Carbon Equivalency bull Modelers estimate a warming of 2K in 60 years so
003Kyear bull Change of 01 in urban albedo will result in 001K a delay
of ~03 years in global warming bull Worldrsquos current rate of CO2 emissions =
25 G tonsyear (41 tonsyear per person) bull Worldrsquos rate of CO2 emissions averaged over next 60
years = 40 G tonsyear bull Hence 03 years delay is worth 12 Gt CO2 ~ 200 Mt
CO2year
39
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
Carbon Equivalency bull Modelers estimate a warming of 2K in 60 years so
003Kyear bull Change of 01 in urban albedo will result in 001K a delay
of ~03 years in global warming bull Worldrsquos current rate of CO2 emissions =
25 G tonsyear (41 tonsyear per person) bull Worldrsquos rate of CO2 emissions averaged over next 60
years = 40 G tonsyear bull Hence 03 years delay is worth 12 Gt CO2 ~ 200 Mt
CO2year
39
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
Equivalent Value of Avoided CO2
bull CO2 currently trade at ~$10ton bull 12Gt worth $120 billion for changing albedo of roofs
and paved surface bull Cooler roofs alone worth $60B bull Cooler roofs also save air conditioning (and provide
comfort) worth over $600B - $900B over 60 years 100 Mt CO2year
bull We would like to start an international organization where the developed countries offer $1 million per large city in a developing country to trigger a cool roofpavement program in that city
40
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
Market Deployment of Cool Color Cars
bull Toyota experiment (surface temperature 10 degC cooler with cool coatings) bull Ford is also working on a similar technology
41
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
42
Effect of AC on fuel consumption US Cal
No of Vehicles (106) 213 26 Milesyearcar (103) 12 12 Fuel Eff [mpg] 20 20 Annual fuel use [109gal] 130 15 Annual fuel expense at 25 $gal [$B] 230 38 Reduced efficiency due to AC 15 15 time AC runs 50 50 AC contribution to fuel use [109gal] 96 12 AC contribution to fuel expense [$B] 24 3
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
Benefits of 28K (5degF) reduction in soak temperature
US Cal Reduction in AC capacity 11 11 Improvement in mpg 18 18 Reduced NOx emission 45 45 Reduced fuel expense ($M) 2876 346 Reduced CO emission (tonneday) 978 1178 Reduced NOx emission (tonneday) 103 124 Reduced NMHC emission (tonneday) 18 22
43
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition
44
Practical Guidelines
bull EPA Guidebook (1992) bull Good practical information bull Greatest focus on trees
bull EPA is working on a new edition