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1
Yogurt and bioethanol: biofuel choices
Dr. Richard Venditti Professor
go.ncsu.edu/venditti
North Carolina State University
Department of Forest Biomaterials
College of Natural Resources, Scholarship Day
December 6, 2011
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3
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Yogurt is good! Or is it?
5
What is a Life Cycle Assessment ?
Life Cycle Assessment (LCA) is a tool to assess the potential environmental impacts of products, systems, or services at all stages in their life cycle [ISO 14001:2004].
Production Transportation Use Disposal
Recycle
Energy Energy Energy Energy
Waste
Waste
Waste Waste
Emissions to
air and water Emissions to
air and water Emissions to
air and water Emissions to
air and water
Recycled Materials
Raw
Materials
Energy
Waste
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Life Cycle Assessment
Interpretation
Impact Assessment
Inventory Analysis
Goal and Scope
Definition
Objective
Parts of this are Subjective
Parts of this are Subjective
Parts of this are Subjective
(allocation)
7
Why is LCA Important?
• decrease the environmental impact of a product
• ensure compliance with government regulations
• reshape company strategy
• help marketing
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Yogurt LCA : One Kilogram of yogurt consumes/emits:
• 1450 grams of CO2e
• 8.9 MJ of energy
• 245 g O2e for eutrophication
• 0.50 g ethene eq. for photochemical
ozone creation potential
Berlin (2008).
9
Yogurt: Carbon footprint:
52% milk production
3% non milk ingredients
10% packaging
6% transportation of ingredients
13% manufacturing
9% distribution
7% refrigeration
2% end of life
Stonyfield Organics, stonyfield.com
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Yogurt LCA : Livestock in total:
• 9% CO2 from human activities
• 65% of N2O from human activities
(manure)
• 37% of methane from human activities
(enteric fermentation)
• 64% of ammonia from human activities
(manure) – acid rain
• Approximately 30% of entire land surface-
dominated by economics
Livestocks long shadow: environmental issues and options –
FAO, www.fao.org, FOOD AND AGRICULTURE
ORGANIZATION OF THE UNITED NATIONS Rome, 2006
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Yogurt LCA :
• Dairy livestock contributes 1.2% to all
GHG emissions worldwide
• Cradle to farm gate milk emissions
contribute 3% to all GHG emissions
worldwide
• Cradle to dairy gate milk emissions
contribute ~3.5% to all GHG emissions
worldwide
• Sevenster and de Jong, 2008
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Yogurt LCA :
• Controversial issue: how to partition environmental
issues between dairy, beef, hide and other products?
• What about the pasture lands and croplands to feed
the livestock and their impact on the environment and
landscape?
13
Yogurt LCA :
• …..we found a strong association between an increased consumption
of refined carbohydrates in the form of corn syrup, a decreased
consumption of dietary fiber, and an increasing trend in the prevalence
of type 2 diabetes in the United States…..
• Lee S Gross, Li Li, Earl S Ford and Simin Liu, American Journal of
Clinical Nutrition, Vol. 79, No. 5, 774-779, May 2004
Dots – corn syrup
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Yogurt LCA :
• Yoplait Yogurt ingredients:
Serving Size: 1 container/ 6oz / 170g
Calories: 170 (about 8% of your daily max)
Calories from Fat: 15 (less than 3% of
recommended daily max)
No fiber
Carbs – 33 grams (11% of the
recommended daily value)
Sugars – 27 grams (more than 5 tsp)
Cultured Pasteurized Grade A Low Fat
Milk, Sugar, Strawberries, Modified Corn
Starch, High Fructose Corn Syrup,
Nonfat Milk, Kosher Gelatin, Citric Acid,
Tricalcium Phosphate, Natural Flavor,
Pectin, Colored with Carmine, Vitamin A
Acetate, Vitamin D3.
Fooducate.com, accessed 12/5/11.
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Yogurt is good?! Actually it is a seemingly innoculous appearing product that
has significant consequences.
Every product or service we use has a consequence, and they
add up.
Its cheap and delicious in the United States!
It turns out that we must make careful decisions about all of the
products and services we think we need!
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1983 Stonyfield Farm is born in Wilton, New Hampshire. The
founding premise: A company can make a great product, make money,
and at the very least not harm the planet!
1992 A system is set up to track energy use, water, and waste.
1995 Started tracking carbon dioxide emissions from our facility
energy use.
1997 Became the first manufacturer in the U.S. (and likely the world) to
offset 100% of facility energy GHG emissions, and wrote a “cookbook”
for other businesses on how to do so.
2006 Began operation of wastewater pretreatment with an anaerobic
digester that converts waste into energy.
2007 Marked the 10th year of offsetting 100% of facility energy GHG
emissions with an investment in wind energy and manure methane
digestion.
2010 Introduced the first yogurt cup made from plants
2011 Began using biodiesel fuel—made from waste vegetable oil—in
some of the trucks delivering yogurt.
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Firm Sales, $
Billions
Profits:
Gross
Profit
Margin
Profits:
Return on
Assets
People Environment
General Mills
Top 2 cereal producer.
2nd highest yogurt
producer
(11% US mkt)
15 39.4 8.8 Health and community Four goals: reducing water use,
energy use and greenhouse gas
(GHG) emissions all by 20 percent,
as well as cutting solid waste
generation by 50 percent by 2015.
Kellog’s
Top 2 cereal producer
13 42.9 11.0 Market place,
workplace,
philanthropy/volunteeris
m for community pillars
Environmental impact reduction,
sustainable agriculture, packaging.
Danone
Top yogurt producer
(17.6% US mkt)
21 51.2 4.4 Values, health/nutrition,
employee wellness,
community service
Carbon footprint, LCA, reduction of
packaging, water use, energy use,
and waste
Stonyfield Farms
Largest and fastest
growing organic
yogurt producer, 1st in
natural food stores
and 4th in grocery
stores
0.09 Not avail. Not avail. Organic farming: don’t
use synthetic growth
hormones, antibiotics,
or genetically modified
organisms.
Intense efficiency of manufacturing
process and effective packaging.
Bought carbon offsets and became
nations first zero emissions
manufacturer.
Organic farming: no pesticides,
chemical fertilizers.
18
Sustainable forest products
life cycle analysis (LCA)
Dr. Richard Venditti Professor
Website: go.ncsu.edu/venditti
(919) 515-6185
North Carolina State University
Department of Forest Biomaterials
19
Bio-refinery: Sustainable Products
Conversion
Process Biomass
Feedstock
Fuels, Energy,
Solid Wood,
Paper, materials,
chemicals
20
Fuel Mandates
Lifecycle GHG Thresholds Specified in
EISA
(percent reduction from 2005 baseline)
Renewable fuela 20%
Advanced biofuel 50%
Biomass-based diesel 50%
Cellulosic biofuel 60%
EISA Renewable Fuel Volume Requirements (billion gallons)
YearCellulosic
biofuel requirement
Biomass-based diesel
requirement
Advanced biofuel
requirement
Total renewable fuel requirement
2008 n/a n/a n/a 9.0
2009 n/a 0.5 0.6 11.1
2010 0.1 0.65 0.95 12.95
2011 0.25 0.80 1.35 13.95
2012 0.5 1.0 2.0 15.2
2013 1.0 a 2.75 16.55
2014 1.75 a 3.75 18.15
2015 3.0 a 5.5 20.5
2016 4.25 a 7.25 22.25
2017 5.5 a 9.0 24.0
2018 7.0 a 11.0 26.0
2019 8.5 a 13.0 28.0
2020 10.5 a 15.0 30.0
2021 13.5 a 18.0 33.0
2022 16.0 a 21.0 36.0
2023+ b b b b
Energy Independence and Security Act, 2007
Billion gallons/year
21
LCA Research Objectives: Develop tools to evaluate the life cycle of
forest-based or other sustainable
products relative to conventional products
Provide input on the discussion of biofuels
and biomaterials
Education
22
LCA Ongoing Efforts:
Personnel
Faculty: R. Venditti, S. Kelley, H. Jameel, D. Saloni, S.
Dasmohopatra, A. Kirkmann
Ronalds Gonzalez (PD, economics, LCA, forestry), Jesse Daystar
(PhD student, process simulation, LCA), Trevor Treasure (PhD,
simulation)
Collaborators, NCSU Forestry, NCSU CE, NCASI
Projects:
Cofiring biomass at coal power plants
Thermoconversion of Biomass to Ethanol, Corrim and DOE
Carbon footprint of paper products, NCASI
NC Bioenergy Options: Biomass and Conversion Processes,
Biofuels Center of NC
Building a Biofuels Industry in the Southeast AFRI USDA
Integrated Biorefinery at Plymouth NC, Domtar, USDA BRDI
Pretreatments for Pellets, Daniel Saloni, SunGrant
Currently looking for graduate students
Multiple assistantships available, $20,000/yr plus tuition+benefits
23
Production Transportation Use Disposal
Raw Materials
Energy Energy Energy Energy
Waste Waste Waste Waste
Emissions to air and water
Emissions to air and water
Emissions to air and water
Emissions to air and water
1.Thermochemical for Low Pressure Gasification: Mixed Alcohols
2.Thermochemical for Low Pressure Gasification: Fischer-Tropsch Fuel
3.Thermochemical for High Pressure Gasification: Mixed Alcohols
4.Thermochemical for High Pressure Gasification: Fischer-Tropsch Fuel
5.Biochemical (enzyme hydrolysis/fermentation to Ethanol)
1.Unmanaged hardwood,
2.Managed hardwood,
3.Managed pine plantations,
4.Forest residues
5.Industrial wastes (organic sludges)
6.Agricultural residues
LCA of Production of Biofuels: Raw Materials and Processes
SimaPro LCA Software
Cradle Gate Grave
Process Simulation
Matrix of Cases:
24
Lignocellulosic ethanol (thermochemical conversion)
decreases GWP by 70%, Cradle-to-grave
8.66E-02
4.57E-03 7.24E-03 1.58E-04
7.45E-02
2.71E-02
-1.80E-01
3.07E-04
3.46E-03
1.29E-01
1.58E-04
7.45E-02
-0.2
-0.15
-0.1
-0.05
0
0.05
0.1
0.15
Total SequesturedCarbon
Raw MaterailTransport
RawMaterials
FuelProduction
FuelTransport
FuelCombustion
kg
CO
2 E
qu
ivale
nts
per
MJ F
uel
Axis Title
Gasoline
Ethanol From Pine
25
Lignocellulosic ethanol (thermochemical conversion) :
consumes 1 unit of fossil energy to produce 4 units of energy
0.24
1.26
26
Biofuels summary
Lignocellulosic biofuels have been predicted to
Reduce GWP by 70%
Conserves non-renewable fuels
Can possibly reduce dependence on oil
A successful wide-spread lignocellulosic fuel industry will impact environment, landscapes and people
LCA’s will be critical to direct this new industry
Allocation issues
Landscape issues
Social and Economic issues
Government policy
27
Questions?
Raw materials Manufacturing Transportation End-use
Land-use
28
Life Cycle Analysis: Pulp and Paper Products
• Extremely difficult to perform LCA on paper:
• Paper is mainly derived from renewable
resources
• Complex furnish and manufacturing,
multitude of products with subtle but
important differences
• Extremely efficient/complex
manufacturing processes using a
majority of renewable fuels
• Paper manufacturing has air/water/solid
emissions
• Paper has several co-products
manufactured
• A recyclable product (open loop)
• Paper is the major component in landfills
and when degrades anaerobically forms
methane
29
LCA of Paper Catalog: Carbon Footprint
29
Kg C
O2/t
on
ne
pro
du
ct
Manufacturing Landfill/Incineration
30
LCA: Catalog System Boundary
NCASI LCA NA P&W Grades, 2010
31
Allocation Methods in LCA:
Choice of allocation method is critical:
0
1000
2000
3000
4000
5000
6000
7000
Cutoff MLWMBR 50/50 Closed LoopRecycling
Quality Loss RMAGWT
Virgin Burden Recycled Burden
Ne
t G
HG
, lb
CO
2e
q/t
on
Paper Task Force
Shared Burden:
# uses
Table 7. Net GHG of office paper from various life cycle stages from the Paper Task Force (2002, pg. 132), waste management is 80/20 landfill/incinerate.
32
Minimum Carbon Price Required to Promote
Biomass Systems:
Several alternatives exist for biomass residuals
from forest harvesting
Leaving biomass on ground
Co-firing green biomass with coal
Co-firing field dried biomass with coal
Co-firing torrefied biomass with coal
Co-firing charred biomass with coal
Applying char to agricultural lands
For a ton of biomass which system:
Has the smallest carbon footprint?
Has the lowest cost?
Has the lowest cost per metric ton of carbon dioxide
saved?
33
Minimum Carbon Price Required to Promote
Biomass Systems: Carbon Footprints
-2500
-2000
-1500
-1000
-500
0
500
1000
1500
2000
2500
Green Wood
Air Dried Wood
Torrefaction
Char
Char toGround
C F
oo
tpri
nt,
lb
CO
2e/t
on
of
gre
en
bio
mass
Note: leaving
residuals on ground
causes decay,
produces a -6 lb
CO2/ton carbon
footprint
34
Cost per Ton of Product
by Distance to Destination
$-
$20.00
$40.00
$60.00
$80.00
$100.00
$120.00
$140.00
$160.00
$180.00
0 20 40 60 80 100 120 140 160 180 200
$/ To
n P
rod
uct
Miles
Green Wood Co-fire Dry Wood Co-fire Torrefied Wood Co-fire Coal Char Co-fire Char to Soil
35
Fuel Cost per MMBtu Electricity
by Distance to Plant
$-
$5.00
$10.00
$15.00
$20.00
$25.00
$30.00
0 50 100 150 200
$/M
MB
tu (
ele
ctr
ica
l)
Miles
Green Wood Co-fire Dry Wood Co-fire Torrefied Wood Co-fire Coal Char Co-fire
36
-50
0
50
100
150
200
0 50 100 150 200 250
Green Wood Co-fire
Dry Wood Co-fire
Torrefied Wood Co-fire
Char Co-fire
Char to Soil
Distance in Miles
Min
imum
Price,
$/m
etr
ic t
on C
O2
(Negative prices indicate that it is less expensive to
fire the biomass than it is for coal at equivalent
eletrical energy production)
Dashed lines: historical high (45) and price 7/2011 (15)
of CO2 as reported by http://www.nytimes.com
/2009/01/21/business/worldbusiness
Minimum Carbon Price Required to Promote Biomass System
37
Minimum Carbon Price Required to Promote
Biomass Systems: Summary
Char to ground has the lowest carbon footprint
Biomass growth and preprocessing and co-firing dominate the carbon
footprint
Transportation distance not important for carbon footprint, very
important for costs
Dried or torrefied wood, under the model assumptions, have the most
potential for commercial viability in a carbon market
38
LCA of bioethanol production via the
thermochemical conversion pathway
Jesse Daystar, Richard Venditti, Hasan Jameel, Mike Jett
North Carolina State University
Forest Biomaterials Department
Forest Products Society’s 65th International Convention on June 19-
21, 2011 in Portland, Oregon.
39
CORRIM Biofuels Research
• Gasification
• Pyrolysis
• Bioconversion
Ethanol
Pyrolysis Oil
40
Aspen Model Overview:
41
Global Warming Potential Cradle-to-grave
8.66E-02
4.57E-03 7.24E-03 1.58E-04
7.45E-02
2.71E-02
-1.80E-01
3.07E-04
3.46E-03
1.29E-01
1.58E-04
7.45E-02
-0.2
-0.15
-0.1
-0.05
0
0.05
0.1
0.15
Total SequesturedCarbon
Raw MaterailTransport
RawMaterials
FuelProduction
FuelTransport
FuelCombustion
kg
CO
2 E
qu
ivale
nts
per
MJ F
uel
Axis Title
Gasoline
Ethanol From Pine
42
Thermochemical Conversion of
Biomass to Ethanol: 69% reduction in
GHG
100%
31%
0%
20%
40%
60%
80%
100%
120%
Global Warming Potential
Gasoline
Ethanol
Lifecycle GHG Thresholds
Specified in EISA
(percent reduction from
2005 baseline)
Renewable
fuela 20%
Advanced
biofuel 50%
Biomass-
based diesel 50%
Cellulosic
biofuel 60%
43
Fossil Fuel Depletion:
4 units of energy produced/1 unit of fossil fuel input
0.24
1.26
44
Conclusions
Biomass growth and emissions during thermochemical
conversion dominate the GHG balance for biothenol production
Production and use of TC bioethanol reduces GHG emissions
by 69% relative to gasoline, qualifies as cellulosic biofuel
The production of TC bioethanol produces 4 units of energy
per 1 unit of fossil fuel consumed
45
Questions?