Lighting and Daylighting Your Way to Zero Net Energy James R Benya, PE, FIES, FIALD, LC (US) Lighting and Daylighting Your Way to Zero Net Energy Buildings

Lighting and Daylighting Your Way to Zero Net Energy

James R Benya, PE, FIES, FIALD, LC (US)

Lighting and Daylighting Your Way to Zero Net Energy Buildings

James R Benya, PE, FIES, FIALD

BENYA LIGHTING DESIGN

West Linn, Oregon, USA

February 10 2011



Efficiency Vermont is a Registered Provider with The American Institute of Architects Continuing Education Systems (AIA/CES). Credit(s) earned on completion of this program will be reported to AIA/CES for AIA members. Certificates of Completion for both AIA members and non-AIA members are available upon request.

This program is registered with AIA/CES for continuing professional education. As such, it does not include content that may be deemed or construed to be an approval or endorsement by the AIA of any material of construction or any method or manner of handling, using, distributing, or dealing in any material or product.

Questions related to specific materials, methods, and services will be addressed at the conclusion of this presentation.



Learning Objectives

By the end of this program, participants will be able to:

Understand the definition of net zero energy buildings

Understand the roles of daylighting, efficient lighting, controls, and

plug load management in net zero energy design & planning.

Understand the relationship between load management and the

effectiveness of on-site renewable generation.

Gain knowledge of tools and techniques for Net Zero Lighting and

Daylighting Design



Course Evaluations



Copyright Materials

This presentation is protected by US and International copyright laws. Reproduction, distribution, display and use of the presentation without written permission of the speaker and/or Efficiency Vermont is prohibited.



US Total Energy Consumption by Source1949-2008

Zero Net means turning the coal, gas, and crude oil trends downward



US Sources of Electric Energy 2007

Source: US Energy Information Administration 2007 data



Present Day

Coal is used to produce about 50% of the electricity in the US and 83% in China. Its use is growing in both countries.

Increase in Chinese power demand adds (2) coal fired power plants per month to the grid.



Present Day

Global climate change is accelerating as greenhouse gas concentration rises faster than expected. CO2 concentration will soon damage ecosystems. .350 is an international movement to reduce greenhouse

gases to 350 ppm .



An international challenge



“Sustainability” is becoming an empty marketing phrase

“Green is the new Black” - NY Times, 2007



On-going debate and pushback



The Promise of Modern Lighting

Beauty, discovery, wonder

Necessary contributions to the functionality of the built environment

Creative contributions to the enjoyment of life



The Reality of Modern Lighting



Lighting Energy Use



The Opportunity in Modern Lighting

Lighting is a prime opportunity to mitigate energy use and greenhouse gas production

70% of lighting energy use is by day

50% of lighting energy use is by older, inefficient technologies

Lighting is about 10% of the problem but it can be 20% of the solution!!!!



Designing Zero Net Buildings

Reduce total lighting energy useFree up capacity for other uses

Reduce on-peak lighting energy useFree up capacity for other uses

Improve the human environmentBetter health

More productivity

Improve the built environmentCapital improvements without capital investment

Reduce human impact and carbon footprintLess energy use

Dark skies at night



What is “Zero Net”?

Buildings that give and take energy from the grid, but in the end, have no “net” use.

Required in California by law for all new residences by 2020 and for all new buildings by 2030.



Basic Zero Net Math

+ ≤



Impact on Energy

©2009 2030, Inc. / Architecture 2030



Impact on Carbon

©2009 2030, Inc. / Architecture 2030



Chartwell School, Seaside, CAAIA COTE TOP 10, 2009 LEED Platinum Zero Net

EHDD Architects

Interior lights off by day Exterior lighting off at night No A/C Practical PV array



Zero Net Options

Measured Grid

Energy Use

Measured

Gas/fossil fuels Use

Net Energy of Building Materials and Construction

CO2 generated by operations

Electricity Energy Use Total Energy

Carbon Footprint

Electric TOU *



Zero Net Energy

Total non-renewable and off-site renewable sources are considered “Debits”

Total on-site renewable sources are considered “Credits”

End of year: a building is “zero net” if there are more Credits than Debits



Zero Net Electric Time of Use (TOU)

Building energy demand profile does not match non-depletable source profile

Excess thermal energy can be stored but excess electric energy is better off returned to the grid as a “bank”

Bank “account” is depleted periodically

Peak users pay a premium

Peak generators are rewarded



Guiding Principles of Zero Net

1. Negawatts cost less than megawatts. Conservation first!

2. Use passive measures as much as possible. Avoid complex systems except as a last choice.

3. Start with the simple, low cost high payback measures



Making Zero Net Work – Conservation First

Standard Building

Reduce Other Uses

Reduce Computers

Reduce HVAC

Reduce LightingLighting

HVAC

Computers

Other uses

Super efficient building

Energy Use



DAYLIGHTINGThe Next Great Frontier of Design

It is the Key to Zero Net



Daylighting’s Challenges

• Four generations of architects and engineers lost to cheap energy• Limited number of qualified architects, consultants and educators

• No established methodology or dominant theory

• Eighty years of bad habits

• Lighting designers must learn to design daylighting



Architecture’s Challenge: Architectural Fashion conflicts with Building Science

•Glass too transmittive – workers moved 10’ back from windows

•Relies too much on low-e for solar gain control

•Passive shading only works on one of four facades

•Curtain wall poorly insulated



Orientation

•This photo faces north!•20-30X too much daylight•Poor insulation•Too much glare on sunny days•Electric lights all on•Glare control material installed by building occupants also to help control heat gain

Architecture’s Challenge: 70 years of air conditioning have taught us a lot of bad habits



Lighting Controls

Engineer’s Challenge: Lighting controls are “too expensive” and lights are left on by day.

“Value” engineering:

Spend $2Million in energy to save $1Million in control system costs



Waste

More than ½ of the electric light energy goes straight up into the sky

Lighting Designer’s Challenge: controlling ourselves from inefficient designs



Daylighting’s Principal Goal – Achieving Energy Balance

Total Energy Cost Savings from Skylightsfor Lighting, Cooling and Heating

Design

-$2,000

-$1,500

-$1,000

-$500

$0

$500

$1,000

$1,500

$2,000

$2,500

0.0% 2.0% 4.0% 6.0% 8.0% 10.0% 12.0% 14.0%

Skylight to Floor Ratio (SFR)

Ann

ual C

ost

Savi

ngs

($/y

r) SAVING

COSTING

Good Design OverglazedUnderglazed



Daylighting’s Benefits

Daylighting can save:

• Up to 100% of lighting demand

• The cooling associated with lighting demand

• Excessive cooling due to sub-optimal daylighting

• Cooling energy coincident with other peaks

Daylighting Provides

• Healthier interior environments

• Higher productivity

• Better interior spaces



Steps to Better Daylighting

Use passive measures first• Climate tuned orientation and shading• Cooling season solar gain control

• Passive exterior components (natural and man made)• High performance glazing

• As much insulation as possible• Skylights• Curtain walls

• Multiple roofs and skins for problem orientations• Simple skylights



Daylighting Dynamics

100000

10000

2000

10

200

LUX

500

SUNLIGHT OUTDOORS

MAXIMUM WINTER LEVEL

MAXIMUM SUMMER LEVEL

DESIGN LIGHT LEVEL

MINIMUM USEABLE LIGHT

EGRESS LIGHTING ONLY

DESIGN PROBLEM:GYMNASIUM500 LUX



Gymnasium Daylighting

PerformanceSacramento, CA USASemi-arid 37° NorthSkylight/floor ratio 4.2%Skylight SHGC 0.32Skylight VLT 0.64Light/heat ratio 2.0Equiv. LPW 232Day/Elec ratio 3Max summer lux ~1500

Annual clear hours 3100Cooling day autonomy is almost 100%Heating day autonomy is >75%

Source: Sunoptics



Toplighting

Modular skylights with splaySource: Sunoptics

Linear toplightSource: Benya Lighting Design



Toplighting

Modular skylights with clerestory

Source: BOORA Architects

Linear toplightSource: Benya Lighting Design



Tubular Daylight Device PerformancePortland, OR USAPacific NW 46° NorthSkylight/floor ratio 3.0%Windows on eastEquiv. LPW 175Day/Elec ratio 2.5Max summer lux ~2000

Annual clear hours 2200Cooling day autonomy is almost 100%Heating day autonomy is <25%

Source: Benya Lighting Design, Solatube



Sidelighting with external shading

Source: Kieran Timberlake Architects



View Sidelighting – South facing, landscape shaded

South facing high performance glazingSource: Benya Lighting Design



View Sidelighting – west facing, vertical fin and blinds

West facing shadingSource: Kieran Timberlake Architects



Diffuse Sidelighting

Diffuse shaded glazing25% window wall ratio.1 U value25% VLT

Source: Benya Lighting Design



Layered Daylighting

Toplight, sidelight, clerestory




Integrated Electric/Daylight

Energy use by day: < 0.15 w/sfTypical for 12 hours1.8 w/hour per sf per day

Maximum evening lighting: < 1 w/sfTypical for 4 hours4 w/hr per sf per day




Building Integrated PV

Can be applied to glazing systemsShading

Lowers VLT

Lowers SHGC



BIPV Daylighting

PerformanceEugene, OR USAPacific NW 44° NorthSkylight/floor ratio 12%South window w/PVSkylight SHGC .22Skylight VLT .28Light/heat ratio 1.27Equiv. LPW 150Day/Elec ratio 2.0Max summer lux ~2000

Annual clear hours 2400Cooling day autonomy is almost 100%Heating day autonomy is <25%Source: Benya Lighting Design



Double Skin – Water Source Heat Pump LEED PlatinumLoyola Information Commons Chicago

Source: SCB Architects, Chicago



Active measuresActive shading

Exterior shades

Blinds and perforated shades

Optical blinds and shades

BIPV

Solar Collecting (rarely a good idea)Heliostats

Fiberoptics and light pipes

Steps to Better Daylighting



ELECTRIC LIGHTINGIntegrated and Minimized

Lewis and Clark Law Library2003 Edison Award of Excellence for Environmental Design



Controls Reduce Use and Harvest Daylighting

Lighting Power Profile at Equinox - Clear

0100002000030000400005000060000700008000090000

100000

Base 8A 10A Noon 2PM 4PM 6PM Base

Time of Day

Wat

ts

Title 24 Allowed

Connected Lighting Power

Actual Power Use

Typical building: 18 Wh/sf/dayEfficient building: 13 Wh/sf/dayDaylighted Building: 2Wh/sf/day



Best Electric Lighting Technology

Low watt sources

LED

Halogen

Fluorescent

HID

Highest Efficacy Sources

Linear fluorescent

High wattage HID

High Efficiency Sources and Luminaires

LED

Plasma HID



Modern Lighting Control Technology

Switching

Motion sensors

Time of day switches

Photoelectric switches

Dimming

Daylighting

Tuning

User control

Systems

Whole building load management

Shading integration



Advanced Lighting and Integrated Design Techniques

• Layered lighting and daylighting• Task and Ambient Lighting Design• Natural ambient integrated lighting• Reduced and controlled exterior street and roadway

lighting• Dark-sky responsive architectural outdoor lighting



Layered daylighting

Layered Lighting and Daylighting Design

Let the architecture drive fenestration choices•Windows•Clerestories•Light shelves•Skylights

Sidwell Friends School

AIA COTE Top 10 2006

LEED Platinum



Layered daylighting

Layered Lighting and Daylighting Design

Let the architecture drive fenestration choices•Windows•Clerestories•Light shelves•Skylights

Sidwell Friends School

AIA COTE Top 10 2006

LEED Platinum

Lights on for photography only



Task and Ambient Lighting

Typical designsAmbient light 40-50 fc 0.8 w/sfTask light 70-100 fc 0.4 w/sfTOTAL 1.2 w/sf

State of the Art DesignAmbient light 20-25 fc 0.5 w/sfTask light 40-50 fc 0.2 w/sfTOTAL 0.7 w/sf



Natural Ambient Sales Lighting

JEWELRY STORE

Tubular daylighting devices with CMH track

NATURA:L AMBIENT LIGHTING DESIGN

Ambient lighting

•Sunny day, 100+ fc•Cloudy day, 10-50 fc•Night 5 fc

•Merchandise lighting

•Sunny day, 300-400 fc•Cloudy day, 200-300 fc•Night, 150-200 fc

CONNECTED LIGHTING POWER 3.1 w/sf



AIRPORT

Metal halide downlights/fluorescent upllghts

NATURAL AMBIENT LIGHTING DESIGN

Ambient lighting

•Sunny day, 150+ fc•Cloudy day, 5-50 fc•Night 5 fc

•Merchandise lighting

•Sunny day, 150-250 fc•Cloudy day, 50-100•Night, 30-70 fc

CONNECTED LIGHTING POWER 2.0 w/sfAVERAGE LIGHTING POWER 0.4 w/sf



OUTDOOR LIGHTING

Extremely important on a zero net building



Reduce or Eliminate Excessive Exterior Lighting

Example: SchoolSchool Building Size 100,000 sf 500 students

Parking Lot and Drives Size 100,000 sf 200 cars

Parking Lot Lighting 10,000 w LZ3, typical

Parking Lot Energy (normal) 44,000 kWh

Parking Lot Energy (aggressive) 4,000 kWh

Savings 40,000 kWh

PV size saved 23.5 pkW (Redding)



Dark Sky Responsive Architectural Lighting

Sacramento Memorial Auditorium2008 Edison Award2008 Edison Award of Excellence for Environmental Design

Aspen Recreation Center2005 IDA Gold Award



TOTAL BUILDING ENERGY CONSIDERATIONS



Plug Load

Office of the Future Survey of California Offices (SCE 2007)

Lighting 1.1 w/sf

Computers 0.7 w/sf

Monitors 0.4 w/sf

Printers and misc > 0.2 w/sf

TOTAL I.T. 1.3+ w/sf



I. T. Power can be as high as 3-4 w/sf in regular spaces



Simple I.T. ChangesUse laptops or thin clients

• Standard office computer 60-120 watts• Laptop 15-50 watts• Thin client 10-20 watts

Use LCD screens

Minimize wall-warts

Employ IT energy management softwareHP Thin ClientNo drivesStandard keyboard, mouse and monitorUSB , Ethernet, and other portsMaximum 50 watts, typical operating power <20 w



Other Plug Loads

Survey Plug Loads DiscoveredOffice of the Future (SCE) 2007 10 buildings

Portable space heaters (10%) 1500w each 1.5 w/sf

Hot/cold water dispenser 500w 0.25 w/sf

Personal refrigerator (2%) 120 w 0.1 w/sf

Personal fan (5%) 25 w <.05 w/sf



Mechanical and Envelope OpportunitiesPassive• Passive solar• White roof• Better insulation• Natural ventilation• Multiple skins

Active• Hot water collectors• Heat pumps (ground or water source)• Dark sky systems• Thermal storage systems



Load Shedding Controls

A system to shed loads to force a better demand profile or simply prevent use at bad times

A system to shed load in response to grid demand and/or time of use costs



See Where We Are At…………….Ordinary Efficient Building

Lights 1.1 w/sf

Computers 1.1 w/sf

HVAC (cooling) 1.0 w/sf

Plug load other 0.5 w/sf

Non-process 0.5 w/sf

DEMAND 4.2 w/sf

Average Use 1.47 w/sf

Annual Use 12.9 kwh/sf/yr

Assuming normal lack of concern for energy use

Super Efficient Building

Lights 0.2 w/sf

Computers 0.5 w/sf

HVAC (cooling) 0.5 w/sf

Plug load other 0.25 w/sf

Non-process 0.25 w/sf

DEMAND 1.7 w/sf

Average Use .26 w/sf

Annual Use 2.3 kWh/sf/yr

Assuming aggressive energy savings



A Net Zero Building will have..Envelope

North facing triple glazed façade

Central north facing clerestory skylight

South facing windows with light shelf

Skylights throughout

Mechanical

Water source or ground source heat pump

Natural ventilation

Green roof with PV array

Good insulation



A Net Zero Building will have..

LightingGeneral lighting 0.3 w/sfTask lighting 0.45 w/sfDigital dimming and controls for all systemsDaylighting designed for >90% effectiveness

Plug LoadsDemand response and management controlsWorkstation sensors>95% conversion to laptops without desktop monitorAll LCD monitors on other computers



LEED PlatinumPractical Costs

The Chartwell School, Seaside CAEHDD Architects, San Francisco





Zero Net Renewable Source



Other Keys to Success

Totally integrated design team

Daylighting is part of schematic design

Owner, architect, engineers and consultants are all part of schematic design

Early definition of goals

Early identification of incentives and rules

Use LEED later not now



Zero Net Buildings - Why Wait for the Future? We can do it today.

For posting of this program see conference proceedings or www.benyalighting.com

Documents

Lighting and Daylighting Your Way to Zero Net Energy James R Benya, PE, FIES, FIALD, LC (US) Lighting and Daylighting Your Way to Zero Net Energy Buildings