US DOE Building Windows and Envelope R&D - Retrofit Focus

Marc LaFranceTechnology Development ManagerBuilding Technologies ProgramOffice of Energy Efficiency and Renewable EnergyU.S. Department of Energy

EcoBuild December 10th 2009

Joseph DeringerVisiting ResearcherBuilding Technologies DepartmentLawrence Berkeley National Laboratory

1

Facing our Energy Challenges

President Barack Obama

“We're using 19th and 20th century technologies to battle 21st century problems like climate change and energy security.”

Remarks of President Barack Obama, Signing of the American Recovery and Reinvestment Act, February 17, 2009

Secretary of Energy Dr. Steven Chu

“Make it white,”Secretary Steven Chu, Daily Show, July 21, 2009

2

Building Technologies Goal

Net-Zero Energy Buildings by 2025Net-Zero Energy Homes by 2020Low incremental cost.

3

-

500,000

1,000,000

1,500,000

2,000,000

2,500,000

2000 2001 2002 2003 2004 2005 2006 2007 2008 2009

US$ (

in th

ousa

nds)

$1.0B

$2.2B

In addition to FY09 funding, EERE received $16.8 billion in funding through the American Recovery and Reinvestment Act of 2009

EERE Budget History (2000-2009)

4

EERE Recovery Act Funding

$16.8B EERE Recovery Act Funding

$2.5

$14.35

EERE Discretionary RD&D

EERE Directed Funding

Amounts are in billion US Dollars

5

Coal power plants – CCS rebuilds with EOR

Coal power plant –CCS new builds with EOR

2.8 3.0 3.2 3.4 3.6 3.80.6

100

150

0.4

-100

-150

-200

-250

50

-50

Cost$2005/ton CO2e

0 1.0 1.2 1.4 1.6 1.8 2.00.2 2.42.2 2.60.8VolumeGt/year

0

Source: December 2008 analysis conducted by EERE with McKinsey using2008 DOE technology performance projections; mid-range case

EERE Energy efficiency

EERE Transport

EERE Power

DOE Nuclear/CCS

Cars fuel economy packages

Light trucks fuel economy packages

Cars Hybridization

Light Trucks Hybridization

Residential electronics

Commercial electronics

Residential buildings – lighting

Residential buildings –new shell improvements

Commercial LED

Commercial buildings –New shell improvements

Commercial buildings –CFL lighting

Biofuels cellulosic

Control systems

Commercial buildings – combined heat and power

Residential buildings –Shell retrofits

Power plant conversion efficiency improvements

Industry –combined heat and power

Residential water heaters

Industrial process improvement

Coal mining -CH4

Hydro-thermal

Enhanced geothermal systems

Manufacturing -HFCs

Existing hydro efficiency gains

Existing hydro capacity increases

Natural gas and petroleum systems management

Residential windows new build

Nuclear

Cars Plug-In Hybridization

Afforestation -pastureland

Solar CSPLand-based wind

Reforestation

New hydro in existing dams

Biomass cofiring

Afforestation –cropland

Distributed PV

Commercial HVAC equipment efficiency

Coal powerplant – CCS new builds

Industry – CCS new builds on carbon-intensive processes

Offshore wind

Coal powerplant – CCS rebuilds

Residential HVAC equipment efficiency

Coal-to-gas existing plants

Car HydrogenFuel CellVehicles

28

10

17

9

1421

Industrial

TransportPower

DOE Nuclear/CCS

Non-DOEBuildings

Technology Share of Abatement Volume%

Coal power plants – CCS rebuilds with EOR

Coal power plant –CCS new builds with EOR

2.8 3.0 3.2 3.4 3.6 3.80.6

100

150

0.4

-100

-150

-200

-250

50

-50

Cost$2005/ton CO2e

0 1.0 1.2 1.4 1.6 1.8 2.00.2 2.42.2 2.60.8VolumeGt/year

0

Source: December 2008 analysis conducted by EERE with McKinsey using2008 DOE technology performance projections; mid-range case

EERE Energy efficiency

EERE Transport

EERE Power

DOE Nuclear/CCS

EERE Energy efficiencyEERE Energy efficiency

EERE TransportEERE Transport

EERE PowerEERE Power

DOE Nuclear/CCSDOE Nuclear/CCS

Cars fuel economy packages

Light trucks fuel economy packages

Cars Hybridization

Light Trucks Hybridization

Residential electronics

Commercial electronics

Residential buildings – lighting

Residential buildings –new shell improvements

Commercial LED

Commercial buildings –New shell improvements

Commercial buildings –CFL lighting

Biofuels cellulosic

Control systems

Commercial buildings – combined heat and power

Residential buildings –Shell retrofits

Power plant conversion efficiency improvements

Industry –combined heat and power

Residential water heaters

Industrial process improvement

Coal mining -CH4

Hydro-thermal

Enhanced geothermal systems

Manufacturing -HFCs

Existing hydro efficiency gains

Existing hydro capacity increases

Natural gas and petroleum systems management

Residential windows new build

Nuclear

Cars Plug-In Hybridization

Afforestation -pastureland

Solar CSPLand-based wind

Reforestation

New hydro in existing dams

Biomass cofiring

Afforestation –cropland

Distributed PV

Commercial HVAC equipment efficiency

Coal powerplant – CCS new builds

Industry – CCS new builds on carbon-intensive processes

Offshore wind

Coal powerplant – CCS rebuilds

Residential HVAC equipment efficiency

Coal-to-gas existing plants

Car HydrogenFuel CellVehicles

28

10

17

9

1421

Industrial

TransportPower

DOE Nuclear/CCS

Non-DOEBuildings

Technology Share of Abatement Volume%

EERE Technologies –Potential Carbon Abatement

Note: Preliminary analysis, under technical review

Energy efficiency measures represent most

of the no-cost options

BTP believes opportunities for Buildings are even greater than predicted

6

Buildings40%

Transport28%

Industry32%

US Energy in Buildings

Electricity – 72% for Buildings

$370 Billion AnnuallyNatural Gas – 55% for Buildings

7

Fenestration Impacts on Building End Use Energy Consumption

Buildings consume 39% of total U.S. energy• 71% of electricity and 54% of natural gas

8

Building Consumption –Envelope Relationship

Heating23%

Cooling13%

Lighting18%

Ventilation3%

Water Heating10%

Electronics7%

Appliances12%

Computers2%

Other12%

Has Impact on 57% of Loads

• 133 Billion $/yr• 13.9% US Energy• 3.5% Global Energy

9

US Window Energy Consumption

• Total Building Energy Use: ~ 40 Quads• Window-Related: 4.1 Q + 1Q Lighting

– includes infiltration losses

“Quad”: 1 quadrillion BTU ≈ 1 EJ ≈ 1% of annual US Energy Consumption

Window-Related Energy Consumption (Quads)

Residential Commercial Heating 1.65 0.96 Cooling 1.02 0.52

Total 2.67 1.48 Daylight: +1 Q

10

1976 Perspective: Code Official’s View of the Ideal Windows

2007 Perspective: Architect’s View of the Ideal Windows

Two Contrasting Views of Energy Efficiency

Window R&D

12

Window R&D – Core Areas

• Commercialize Cost Effective R5 Windows

• Develop Affordable Dynamic Windows

• Develop Next Generation of R10 Windows

• Promote Efficient Products with Enabling Research

• Develop Integrated Daylighting Strategies

• Develop Fenestration Test and Rating Standards Internationally

13

Next Generation of Windows• Highly Insulating

– Goal U value 0.10 (SI U value 0.56)– Possible vacuum glazings

• Dynamic solar control– Passive heating– Dramatic peak cooling reduction– Market ready, prices will drop with more investment

Prototype – Concept Window (Highly Insulating and DynamicU Value 0.18 (SI U value 1.0)SHGC 0.04 – 0.34)Low cost unsealed center lite

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Vision: Energy Losers --> Neutral --> Net Energy Suppliers

• Heating climates– Reduce heat losses (U) so that ambient solar

energy balances and exceeds loss– Need very low U but moderate solar gain

• Cooling climates– Reduce cooling loads: very low SHGF– Static control -> dynamic control

• Mixed climates– Requires dynamic solar control

• All climates– Replace electric lighting with daylight

• Electricity supply options– Integrate Photovoltaics with Glazing

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As we move towards ZEB, windows will play an important role and offer a large opportunity for energy savings –Passive Heating

Bars above black line represent window energy loadOutlined in ASHRAE and ACEEE Peer Reviewed Papers

Highly Insulating and Dynamic Windows

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Single Glazed w/Storm, $1310

Double Glazed, $1218

Double w/Low-E, $1120

“SuperWindow”, $960

House with no windows, $1000

Savings from Better WindowsAnnual Heating Cost simulated for a heating climate

Conclusion: Good windows outperform insulated walls in winter!

17

“Evolution” of Advanced Windows

• Highly insulating systems– Reduces winter heating loads– Multiple technologies for glass

• Aerogel• Vacuum glazing• Multipane, low-E gas fill

– Better Frames– Climate dependence– Cost

• Dynamic windows for solar control– Dynamic optical switch from high transmission to low transmission– Reduces summer cooling load; reduces glare – Multiple technologies

• Electrochromic, thermochromic, photochromic, LCD,…– Integration with window, building– Cost

18

New Sash and Frame Technologies

• “New” Materials– Fiberglass– Thermoset plastics– Foam– Composites - wood fiber and vinyl

• Hybrid Designs– Metal, vinyl clad– Structural reinforcements– Co-extruded– Metal-Plastic-Wood hybrids

19

Storm Windows:Interior and Exterior

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Next Generation Prototype “Zero Energy” Window

• Current Prototype– Dynamic Glazing; SHGC (0.04 – 0.34)

• Electrochromic glazing– Highly Insulating; U Value 0.18, R 5.6

• Ongoing R&D– Increased dynamic range– Cost-effective production– Frame heat transfer R&D

(50% of heat lost through 20% of area)– Systems benefits:

• Better comfort• No perimeter ducts• No central heating system??

21

Highly Insulating R5 Production Engineering Solicitation

• DOE Selected GED Integrated Solutions in partnership with PPG, and other major window companies

• Goal – Affordable R5 – (U value of 0.22 or less for operable window

and 0.20 or less for fixed window) – with price premium less than $4/ft2 compared

to conventional double pane low e • Multiple paths to market, window

companies and IGU sales– Product availability 12 – 24 months– Second round RFP closed Aug 18th

– 50% cost share requirement– Strong response, evaluation underway

22

Savings with Clear and Low-E Storm Windows

• Whole house heating energy savings over a winter season in Chicago for new storms:– Clear storm windows 8-18%– Low-e storm windows 19-27%

• Estimated U-values:– Clear storm windows: 0.49 Btu/h-ft2-F– Low-e storm windows: 0.36 Btu/h-ft2-F

• Payback: 3-12 years

23

Windows Volume Purchase

www.R-5WindowsVolumePurchase.com

R5 (~U 0.2) and Low E Storm Volume Purchase

Develop Buyer Groups

Develop Draft RFP Specifications with Buyers and Possible Manufacturer Bidders

Issue RFP – Dec 2009

Make Awards for Purchasing Schedule

Promote Winner’s Products with Partners

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What are the Best Solar Optical Properties for a Window Anywhere in the U.S.?

Varies with Location and Orientation.

Varies with Season and Weather.

Varies with Occupant Use Patterns

So the best solution is a window whose properties are variable.

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Solar Load Control

• Minimize Cooling Loads but admit Daylight

Conventional Options:• Glass: Clear - Tinted - Reflective• Overhangs, awnings, fins,

vegetation• Shades, blinds, drapes

• Goal: “Cool” Windows and “Smart” Windows

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Spectrally Selective “Cool” Glazings

• Spectral control- transmit light, reject near-IR heat

• Equal daylight with only 50% of solar gain

• IG to minimize SHGC

Technology:• Selective Absorbers

– blue-green tints• Selective reflectors

– modified low-E coatings– coated glass and plastic– Multilayer dielectric

Transmittance -vs- Wavelength

27

Light to Solar Gain Ratio

Light to Solar Gain Ratio for insulating glass units for all glasses in LBNL IGDB

LSG = 1.0LSG = 2.0

LSG: Light to Solar Gain Ratio = Tvis / SHGC

Tvis

SHGC

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Smart Coatings for Dynamic Control of Windows Balancing Cooling and Daylighting

• Flexible, optimized control of solar gain and daylight

• Passive control– Photochromic - light sensitive– Thermochromic - heat sensitive

• Active control– Liquid Crystal– Suspended particle display (SPD)

– Electrochromic• Active control preferred; but

requires wiring windows for power and control

“OFF”

“ON”

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Electrochromic Field Tests 1999

• GSA Building • Performance

assessment -Understand EC operation in a real building:– color – glare– privacy – switching speed– peak load – energy savings– occupant impacts

30

Engineering and Occupant Response Studies with Switchable Electrochromic Windows

• LBNL Façade Field Test Facility (2005-06)

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FY09 Integrated Daylighting and Smart Window Demonstration in EE-1 Conference Room

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Characteristics of SuccessfulDaylighting Systems

• Designed as Integrated Building System– Envelope <-> Lighting <-> HVAC

• Provide Daylight Control– Spectral control to reduce cooling loads– Dynamic control of intensity and direction

• Support changing Occupant Needs:– performance, comfort, satisfaction

• Decision support tools for Architects, Engineers,...– design/analysis across life cycle

• Link Design --> Operations and Maintenance

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Directional Light Control

• Conventional control of direction of light– Glass block– Fritted glass– Shading systems– Light shelves

• New Options– Prismatic glazings – Holographic materials– Laser cut panels– Light pipes– Fiber optics

• Dimmable lighting• Addressable• (Affordable) (1/3 original cost estimate)• (Multifunctional)

Intelligent Lighting and Shade Control

New York Times office with dimmable lights and automated

shading

Occupied 2007

• Automated Shaded

• (Multifunctional)

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WINDOW6 Software Suite

Design /Simulation Tools

DOE-2, EnergyPlusRadiance

THERM(Window

Frame)

Optics(WindowGlass)

WINDOW(Whole Window)

IGDB(Specular Glass Data Source)

CGDB(Complex Glazing Data Base)

RESFEN(Whole Building

Residential)

COMFEN(Whole Building

Commercial)

http://windows.lbl.gov/software

NFRC Ratings

and Labels

• Design tools for advanced products• ISO 15099 Compliant• NFRC Ratings

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Commercial Windows Websitewww.commercialwindows.org

37

Window Technical Targets

Characteristics Units Calendar Year

2003Status 2007 Status 2010 Target 2015 Target 2020 Target

Energy Consumption Improvement*

Reduction in Window Energy Use

Base ENERGY STAR (Low

E)20-30% 30-40% 40-50% 40-60%

1. Dynamic Solar Control

Incremental Price ($/ft2) 85-100 50 20 8 5

Size (ft2) 8 16 20-25 25+ 25+

Visual Transmittance 60 to 4% 60 to 4% 65 to 3% 65 to 2% 65 to 2%

SHGC 0.50 to 0.10 0.50 to 0.10 0.53 to 0.09 0.53 to 0.09 0.53 to 0.09

Durability (ASTM Tests) Medium High High High High

Dynamic Response(Speed/Variable Tint) Slow/On-off Slow/

On-offSlow/On-off

Moderate/Variable

Fast/Variable

2. Highly Insulated Windows

U-Value 0.33-0.50 0.20-0.25 0.17 0.10 0.10

Incremental Cost ($/ft2) IG Base Cost: 3 5 6 4 3

3. Daylight Systems

Lighting Energy Savings 40% 50% 50% 60% 60%

Perimeter Zone Depth (ft) 12 15 20 20 30

Incremental Cost ($/ft2) 3 8 8 6 6

4. Enabling Technology Research for Efficient Products

Tool Capability for Residential (R), Commercial (C) and New Technology (N)

R – YesC – NoN – No

R – FullyC – Partial

N – No

R – FullyC – PartialN – Partial

Assess need for

industry support

Assess need for

industry support

38

Goals: Output

• R5 Highly Insulated Windows– Needs to be no more than $2 to $4 per square above double

low e– Available within 12 to 24 months– Need for ZEH in mixed and cold climates, ZEB in cold (maybe

mixed)

• Dynamic Windows– Needs to be no more than $5 to $10 above double pane low e– Affordable products should be available in the 2015 time frame– Dramatic peak cooling load reduction, promotes daylight,

passive heating in mixed climates with double low e now, and in cold climates when combined with vacuum glazing

39

Goals Output (continued)

• R10 Highly Insulated Windows– Until FY10 limited funding received, major at risk item. Minimal effort

in the past due to funding constraints. Smaller market than R5. – Cost needs to be in the $3 to $6 per square foot above double low e.– Anticipate ARRA RFP to provide new project. Old EverSealed

project on hiatus but reinvigorated within last 6 months.– Cannot commit to schedule since just received resources, goal is to

have affordable products in the 2015 to 2018 time frame.– Needed for ZEH/ZEB in cold climates

• Daylighting– Small project prior to FY10, initiating major increase in activity in

collaboration with CEC. – Moving from a 200 to 400K project to a 2.5M project annually. – More planning and coordination required. – Age old opportunity, needs to be fully planned and coordinated with

Commercial Team.

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Subprogram Status in five years (2015)

• Accomplishments– R5 Windows widely available from multiple sources at cost effective

prices– Dynamic Windows available from multiple sources at affordable prices

for numerous applications but might not yet be fully cost effective for energy efficiency. May be cost effective when full consideration of impacts including increasing value of peak demand.

– Retrofit Products including blinds, awnings, shades, etc are fully rated by NFRC and have greater attention of voluntary programs.

• Remaining Tasks to Achieve ZEB– R10 Windows “truly” commercialized but require greater production

capacity to be cost effective– Daylighting Strategies are much more prevalent but still require more

work to be widely available– Enabling Research – like changing the oil, needs to continue to support

emerging technologies

41

How to Achieve Goals: Critical Paths

• Critical Paths: Residential– Highly insulating – High Solar Gain with Dynamic and Vacuum Glazing (dependent upon

cost compared to other non-window strategies)– R5 low risk, R10 and dynamic cost effective for residential much

higher risk– Conventional multi glazed products reduce solar heat gain potential

• Critical Paths: Commercial– Dynamic windows can provide daylight opportunity that has not yet

become market viable– Peak demand is critical for ZEB

• Why are the selected paths the best way to achieve goals– Windows are the weak link in the building envelope– External shading not fully effective and difficult to maintain/wash

windows, etc– ARPA E just selected and awarded a 4.9M dynamic window project

this is 5 times our previous awards. More funding than the entire windows program prior to FY10.

Envelope R&D

43

Envelope R&D – Core Areas

• Next Generation of Attic/Roof Systems• New Material Development

– Dynamic and Advanced Insulation– Dynamic membranes– Dynamic roof surfaces

• Advanced Walls• Initiate Foundation Systems• Enabling Research

– Cool Roofs– Moisture design, analysis and modeling– Air barrier– Standards development

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• Advanced walls to reach R20 (U = 0.28 SI) in 3.5” (9cm) cavity, exterior insulation systems, R30 (U = 0.19 SI) total wall

• Next Generation of Attic/Roof System to save 50 Percent Energy

• New Material Development– 100 R&D Award in 2009

for phase change material (PCM) insulation

– Higher performing foams and aerogels

– Dynamic membranes

Thermal Envelope R&D

45

Next Generation of Roofing/Attics

• Integrated solutions for building type and climate• Key elements to develop and integrate

– Cool Roofs (lighter colors and near-infrared (NIR) reflective pigments)

– Thermal Mass– Above Deck Ventilation– Radiant Barriers– Location and Higher Performing Insulations

46

Next Generation Roof/Attic R&D Concepts

ShinglesFoil backed OSBUpperair channelRadiantbarriers

Upperair channel

Lower airchannelInsulation w/ foilGypsum board

PCMs

47

PCM Shaves Peak Demandand Reduces Night Sky Losses

Peak Demand Reduction

Potential to Reduce Peak by 90 Percent – Measured Data

Cost effective solutions for hot climate should achieve 50 percent reduction (residential)

48

What is a Cool Roof?

CRRC only looks at surfaceproperties:

•Solar Reflectance•Thermal Emittance

CRRC does not set minimum requirements

Credit: Significant material in this presentation is from the Cool Roof Rating Council

49

Real World Example

Photos from the CEC’s Consumer Energy Center, courtesy of Hydrostop

81 C 34 C

50

Energy Savings Benefits

• Lower roof top and building temperatures–Less heat transfer–Increased occupant comfort–Reduced AC load

• Lower building occupant’s electricity bills• Reduce peak electricity demand (avoid black-outs)• Through cool roof and other urban heat island

mitigation measures (cool pavement, passive cooling designs), avoid the need for the addition of air conditioning that is driven by increased wealth

LBNL estimates Worldwide energy savings of $27 billion (2008)

51

Environmental Benefits

• Reduced energy consumption means less air pollution from power plants

• Global warming mitigation• Reduce Urban Heat Island Effect

–Lower ambient air temperature –Improves local air quality–Reduction in heat and

smog-related health issues

52

Comparison of Cooling Loads (Heat gain) Relative to White Control System

Garden Roofs Show Improved Performance - Preliminary Results

53

DOE/ORNL Conducting In-depth Air Barrier Research

• Sophisticated energy performance measurements

• Supports real world performance and code activity

• 20 wall panels with 13 manufacturing supplier partners and Syracuse Univ.

• Needed to support higher code levels leading to ZEB

54

Solutions you can install today!

• Cool roof with reflective IR pigments, metal, clay tile, concrete tile, asphalt (still limited)

• Cool wall coatings with reflective IR pigments and new vinyl siding with same surface coatings

• Moisture tolerant Exterior Insulation Finishing Systems (EIFS) with drain plane

• Broad range of insulation systems including new aerogels for stud caps and thermal shorts

55

Application:• Thermal bridge in steel and wood framing• Supplied in strips ⅜” thick x 1 ½” wide x 8’

long• Applied onto a building’s framing, inside or

outside, prior to sheathing. • Applied with a peel-and-stick adhesive

backing or staples• Adds an R-4.0 to standard wall framing• Does not alter standard construction

ASPEN Aerogel Supported by DOE via Competitive Solicitations

56

Envelope Technical Targets

Advanced Attic/Roof Technology TargetsCharacteristics 2009 Status 2010 Target 2015 Target

Advanced attic/roof system

R-30 to R-38 Dynamic annual performance equal to conventional R-45

Improved dynamic annual performance at no extra cost

Enhanced reflectivity on attractive dark-colored roof products

30% solar reflectivity on premium-priced products

40% solar reflectivity Wider color space and increased availability on regular products

Advanced Wall Systems Technology Targets

Characteristics 2009 Status 2010 Target 2015 Target

Advanced wall systems

Static R-20 prototype in 3.5 inches thick space

Dynamic annual performance equal to conventional R-25

Improved dynamic annual performance at reasonable extra cost

Enhanced reflectivity on attractive wall coating products

30% solar reflectivity on premium-priced products

40% solar reflectivity Wider color space and increased availability on regular products

57

Goals: Output • Next Generation of Attic/Roofs

– 50% Final Design for Hot Climate Ready for Building America ($1.00 to $1.50 per square foot)

– Mixed and Cold Climate still in development– More cost effective option than R50/Heel Truss Solutions

• New Materials– Dynamic insulation commercialized, still has cost premium – Cost effective today for some applications, wide spread cost

effective in the 2012 - 2014 time frame– Dynamic membranes – performance fully characterized (perm vs

relative humidity chart) but still have not found viable manufacturer partner

– Dynamic roof surfaces – variable solar reflectivity, prototypes had great performance but low durability, still in development

• Advanced Walls – EIFS research completed, viable solutions for new and retrofit – Advanced SIPS in development for higher performing phenolic

foams– Double stud evaluation

58

Unaddressed Opportunities

• ARRA Funding and Priority Items address most unaddressed opportunities –BUT HOW DOES THIS GET MAINTAINED??

• Greater support for demonstrations/case studies of advanced products

• Growing demand for technical support for retrofit programs – limited resources

• Envelope program has multiple technology paths that reduces risks

59

Contact and Information Resources

Stephen SelkowitzBuilding Technologies DepartmentLawrence Berkeley National LaboratoryBuilding 90-3111Berkeley, CA 94720 USAE-mail: SESelkowitz@lbl.gov

More Info: http://windows.lbl.govNew York Times projecthttp://windows.lbl.gov/comm_perf/newyo

rktimes.htmAdvanced Facades projecthttp:lowenergyfacades.lbl.govhttp://gaia.lbl.gov/hpbfCommercial Web Sitehttp://www.commercialwindows.umn.edu

P Marc LaFrance, CEMTechnology Development ManagerBuilding Technologies ProgramOffice of Energy Efficiency and Renewable EnergyUS Department of Energy

marc.lafrance@ee.doe.gov1-202-586-9142Fax 1-202-586-4617www.eere.doe.gov