1. Changing the World; One Window, Building, City, Country at a Time…. Effective Solar Shading: From Components to Measured Whole Building Energy Impacts Steve Selkowitz, Charlie Curcija Windows and Envelope Materials Group Building Technology and Urban Systems February 29 th 2012

2. Overview U.S. Window Energy Situation and Goals Characterizing Energy Efficient Windows –Components to Systems –Systems to Performance Markets: Residential, Commercial –Ratings, Standards –Education and Deployment Programs Collaboration Opportunities 2

3. Bloomberg BusinessWeek Magazine 2/27/2012

4. Innovation Pathways ++ ++ Tools and Knowledge Base Enabling Technologies: Simulation and Testing Innovative Products High Perf Buildings Manuf. A/E Firms

5. Fenestration Impacts on Building Energy Consumption Buildings consume 40% of total U.S. energy 71% of electricity and 54% of natural gas Windows Do Not Directly Consume Energy Allocating Impact on End Use Energy is a Challenge 42% 57%

6. Business and Policy Energy Context Severe downturn in New Construction Markets -> More Retrofit Future energy costs trends?, unclear policy on carbon?? Technologies reaching inflection points –E.g. Double glazing Triple: new factory investment –New technologies: smart glass –Shift from Components to focus on Integrated Systems Updates to Mandatory Codes and Standards Updates to Voluntary Programs: e.g LEED, EnergyStar New State, Federal Energy Savings Requirements –E.g. California: all new buildings net-zero by 2030 New Performance Disclosure requirements like EPBD –City, State now; will likely spread; How is Envelope Assessed? 6

7. U.S. Windows Context –Windows cost Building Owners ~ $50B/yr in Energy Bills –Highly visible component- window selection is complex –Long-Lived Component- one chance to make the right decision! –Vision: change windows from net loss to net supply LBNL Program Supports Zero Energy Window Vision –Comprehensive program: spans materials science to product R&D to systems integration –Technology – Policy - Codes/Standards – Education/Training –Research – Development – Demonstration – Deployment –All Climates, All Building Types, New and Retrofit –Significant Industry Collaboration and Cost Share –Measurable impact on technology, products, energy savings –International Collaboration Windows, Facades and Daylighting

8. Program Vision: Zero-Energy Window Energy Losers --> Neutral --> Net Suppliers Heating climates –Reduce heat losses so that ambient solar energy balances and exceeds loss –Need lower heat loss technologies Cooling climates –Reduce cooling loads –Static control -> dynamic control All climates –Replace electric lighting with daylight Electricity supply optionsElectricity supply options –Photovoltaics-building skin as power source

9. Successes in U.S. Window Markets (Example: Improved Insulating Properties in Residential market) 1973: Typical Window: –clear, single glazed, –double or storm window in north, –U average = 4.8 W/m 2 -K 2003: Typical Window: –95% double glazed –50% have a low-E coating –30-65% energy savings vs. 1973 –U average = 2.5 W/m 2 -K 2030: Future Window: –Zero net energy use (typical) Net winter gain; 80% cooling savings –U average =.6 W/m 2 -K –Dynamic solar control Starting Today –Window -> Window System w/Shading –Annual Performance; Operations

10. Challenge for Window Shading/Attachments 10

11. Next Steps/Challenges in U.S. (Globally) Well Developed and Accepted (accurate) Methods to characterize Window Properties –New Technologies Can Be Added Extend to Shading/Insulating Attachments Properties-> Performance –Metrics, Ratings and Standards Applications –Residential: New, Retrofit –Commercial: New, Retrofit Deployment –Market based programs –Education Materials

12. FROM COMPONENTS TO SYSTEMS System Layer Material Building

13. SHADING DEVICE LOCATION Indoor Outdoor Integral

14. USE OF REAL-TIME DETAILED COMPUTER MODELING Optical modeling by ray-tracing of geometrical shapes that have base material properties already measured Optical modeling of material properties based on detailed description of material structure Thermal modeling (convection heat transfer) by computational fluid dynamics/heat transfer (CFD/CHT) numerical modeling Optical Thermal Conduction Convection Visible & Solar Far Infrared

15. EXISTING MODELING METHODS – Horizontal louvered blinds (Venetian blinds) Vertical louvered blinds Woven Shades Perforated Screens

16. MISSING MODELING METHODS Horizontal and vertical projecting attachments Honeycomb (cellular) shade. General scattering shade. Projecting attachments consisting of irregular patterns type of materials

17. COMPLEX GLAZING DATABASE (CGDB) Conceptually comparable to International Glazing Database (IGDB) Designed for optically complex materials and devices –Venetian Blind slats –Woven Shades –Scattering (Diffusing) Interlayers –Scattering glass –Fritted Glass –Cellular shades –Other scattering layers/systems

18. EXISTING PRODUCT DATA in CGDB (2011) Initial CGDB content: –100 Woven Shade screens –14 Frits –7 Venetian Blinds –3 Diffusing Laminates WINDOW 6.3 and WINDOW 7 Available at: http://windows.lbl.gov/software/CGDB http://windows.lbl.gov/software/CGDB Shared Global Database?

19. SHADING DEVICES WITH KNOWN ANALYTICAL MODELS Each Angle of incidence CGDB M (Scattering Material Database)

20. Example Work Flow for Venetian Blinds Measure slat material in spectrophotometer Create XML data file and submit to LBNL LBNL adds to CGDB Create Blind Geometry in WINDOW Slat spacing, width, angle Create Glazing System Perform Calculation Angular U- factor, SHGC, VT COMFEN/R ESFEN/Ene rgyPlus input Radiance input file Not Implemented Yet Manufacturer / Optical Lab Simulator Rating Info U-factor, SHGC, VT,

21. Tvis vs Hour/Month of year Tvis vs Altitude/Azimuth Transmittance Properties of a 45 Degree venetian blind in Stuttgart Tvis vs Profile Angle

22. OTHER SCATTERING AND DIFFUSING PRODUCTS CGDB (Scattering Layer Database

23. Scope of WINDOW 7/THERM 7 Specular glazing Scattering glazing Vacuum Glazing Perforated screens Horizontal and Vertical louvered blinds Woven shades Glazing deflection IGDB/CGDB Third party developers interface

24. Extending Glazing and Façade Decision Support Tools to Include Shading/Attachments Download http://windows.lbl.gov/software/ FY10 ~ 37,000 Downloadshttp://windows.lbl.gov/software/ Radiance Lighting /Daylighting THERM (Window Frame) Optics (Window Glass) WINDOW + Shading Systems (Whole Window) IGDB (Specular Glass Data Source) CGDB (Complex Glazing Data Base) RESFEN (Whole Building Residential) COMFEN (Whole Building Commercial) Commercial Windows Website Efficient Windows Website Design /Simulation Tools Angular SHGC/U/VT (Rating/Lableling) ? EnergyStar

25. MEASUREMENT METHODS Measurement of bi-directional transmittance and reflectance of scattering products Measurement of bi-directional transmittance and reflectance of scattering materials (thin material coupon size) Thermal measurements of window attachments stand-alone and attached to prime windows Thermal measurements of products with complex geometrical surfaces Optical measurements of projecting attachments Thermal measurements of projecting attachments

26. Tools for Glazing/Shading/Daylighting Measurement + Validation Façade/daylighting test facility Integrated Systems testbeds Mobile Thermal Test Facility IR Thermography chamber Large integrating sphere Optics laboratory Scanning Goniophotometer HDR Imaging Field Data Collection systems Commissioning systems Virtual Building Controls Testbed Daylighting controls laboratory

27. MEASUREMENT OPTIONS FOR OPTICAL PROPERTIES Goniophotometer: –Detailed angular resolution –Slow/expensive and only available at LBNL and a few other places. –Limited number of wavelengths. Spectrophotometer: –Only normal incidence –Full spectral resolution Spectrophotometer + angle tubes: –Limited number of angles (9 currently) –Full spectral resolution Integrating sphere

28. MEASUREMENT DEVICES FOR OPTICAL MEASUREMENTS Spectrophotometer –Venetian blind slats –Fritted glass –Diffusing laminates Angle Tubes –Woven shades / insect screens Large Integrating Sphere – Tvis, large sample Goniophotometer –All Other Complex systems –BSDF

29. VIRTUAL GONIOPHOTOMETER (VGP) Virtual Goniospectroradiometer in Ray Trace software Ray Traced Geometric / Optical model

30. STANDARD METHODS OF EXPRESSING PRODUCT PERFORMANCE Indices of performance (U, SHGC, VT) Detailed performance information (angular SHGC, angular VT, BSDF, breakdown of convection and radiation heat transfer) Annual energy use (EP) Model any house/office, could form basis for seasonal or annual metrics –RESFEN, COMFEN in U.S.

31. BUILDING ENERGY SIMULATION OUTPUT Output to COMFEN Output to RESFEN Model any house/office, could form basis for seasonal or annual metrics

32. EDUCATION MATERIALS Information for building professionals –Designers: Architects, Engineers –Standards, Code Officials Information for consumers Information dissemination mechanisms –Web site –Fact sheets –Regional guides Product selection tools –Qualitative –Quantitative

33. Residential Window Market Education Material www.efficientwindows.org -daily visitors > 2,000 in 2009 Residential Windows: A Guide to New Technology and Energy Performance Three editions: 1996, 2000, 2007 Fact sheets, guides Online Window Selection Tool Product data from EWC members Windows and Skylights but no Attachments 33

34. BROCHURES FOR CONSUMERS, CONTRACTORS AND BUILDERS

35. Exterior Shades and Roller Shutters 35 - Accurate performance prediction - Improved simulation tools - Product Performance data - Validation of window retrofits through field testing Field testing protocol for winter and summer performance -Energy Star Ratings? -Voluntary Programs -Code Programs -Information Programs, Websites -Tools for Purchase Decisions

36. WEB-BASED QUALITATIVE PRODUCT SELECTION TOOL

37. 0.270.36 0.38 Best Window Wood Ultimate Double Hung Low-e / AIR

39. SMART LABELS – Product Selection with Smart Phone Apps Select Optimized Windows in your Local Building Supply Center

40. Commercial Buildings: Controlling Dynamic Shading Advanced Technologies: Sensors; Controls; Hi R windows, Cool coatings; Switchable coatings; Automated Shading; Daylight-redirecting Operable windows, Advanced Technologies: Sensors; Controls; Hi R windows, Cool coatings; Switchable coatings; Automated Shading; Daylight-redirecting Operable windows, Program Activities: Simulation Optimization Lab test Field Test Demonstrations Standards Program Activities: Simulation Optimization Lab test Field Test Demonstrations Standards Human Factors: Thermal comfort Visual comfort Satisfaction Performance Human Factors: Thermal comfort Visual comfort Satisfaction Performance Business Case Manufacturing Installation Commissioning Reliability Cost Business Case Manufacturing Installation Commissioning Reliability Cost Advanced Facades and Daylighting: Program Goals: Net Zero Energy Balance for New and Retrofit Enhanced View and Thermal Comfort Reliable, cost effective operations Tools to design, optimize, specify, control Adoption/diffusion throughout industry Advanced Facades and Daylighting: Program Goals: Net Zero Energy Balance for New and Retrofit Enhanced View and Thermal Comfort Reliable, cost effective operations Tools to design, optimize, specify, control Adoption/diffusion throughout industry Application: All climates All Building types New-Replacement-Retrofit Application: All climates All Building types New-Replacement-Retrofit Decision Tools Books, Guides Websites Simulation Tools Testbeds Decision Tools Books, Guides Websites Simulation Tools Testbeds Partners Manufacturers Owners Architects Engineers Specifiers Code officials Contractors Utilities Partners Manufacturers Owners Architects Engineers Specifiers Code officials Contractors Utilities

41. LBNL Façade Testbed Facility 2007-2009 Automated Shading 2003-2006 Electrochromic windows Industry Advisory Groups: Manufacturers Glazing, Shading Framing, Lighting Controls Designers Architects, Engineers Specifiers Owner/Operators Public, Private Utilities Berkeley, South facing 3 Rooms Changeable façade Lighting, HVAC Heavily instrumented Static/Dynamic Occupant Studies Controls/Automation

42. Comparative Shading System Performance

43. Time Lapse from Tests in LBNL Façade Test Facility: Interior Daylight Luminance Patterns with Dynamic Shading Automated Shading Controls Glare Throughout the Day LBNL Façade Test Facility 12 3 654 321

44. FLEXLAB Testbed Facility - 2013

45. Exploring Intelligent Control Systems Maximum performance requires full integration with building systems

46. Dynamic windows: Model-Based Controls (MBC) Need: –Real-time control of operable façade components enables more optimal whole building systems integration –Conventional open-loop or closed-loop PID control of commercial systems produce sub- optimal impacts on HVAC and lighting systems Goal: –Create low-cost, reliable, performance based control solutions to optimize energy and peak demand savings, minimize discomfort, and improve IEQ –Target: 30-50% annual energy use savings –Determine value of MBC for industry: Aerospace & transportation model for rapidly prototyping complex control systems; does it work for facades? Automated awning system with MBC to optimize daylight and solar control Research on Daylighting and Advanced Facades

47. System Integration: Investment Tradeoffs Heating Cooling Lighting Peak Cooling Load Chiller Size Lighting Design Strategy Energy, Peak Electric Demand Central Power Generation $ $ $ $ $ Initial Cost Annual Cost Office Eq. Onsite Power Generation $ $

48. Dimmable lighting –Addressable –Affordable (1/3 original cost estimate) –Multifunctional Automated Shading –Cooling load control –Glare control New York Times HQ New York Times office with dimmable lights and automated shading Occupied 2007 From Test Labs to Large Buildings

49. Approach: Test Shade System Performance in a Full-Scale Mockup Shading, daylighting, employee feedback and constructability: ~4500 sf mockup Concerns with glass facade: Window glare (Tv=0.75) Control of solar gain/cooling Daylight harvesting potential Real sun and sky conditions near construction site, 12-month monitored period Extend to all orientations with simulation North A B

50. PG&E @ LBNL 2/16/2012 Website and On-Line Tools; Custom Design Guides

51. COMFEN: Façade Early Design Tool Website: www.commercialwindows.org - Models Shading Systems: Thermal and Daylighting Impacts - Energy, Carbon, Comfort… - European Cities included

52. COMFEN 4.0 – FAÇADE OPTIMIZATION

53. Light Redirecting Louver system: Hourly/Monthly energy savings performance by depth in room 10 ft 30 ft 50 ft

54. –Lighting energy savings in 60-ft deep space: 40% (LightLouver), 28% (45° blind) –Glare: 1-5% (LightLouver), 0% (45° blind) –Optimized for 10AM-2PM, south, winter & summer altitude angles, clear sky Hourly/Monthly glare index

55. COLLABORATIVE RESEARCH New IEA Task?? or…. Hold kick-off meeting at LBNL: 6-9 months? Define subtasks –Define Scope and Priority –Optical properties of complex products –Thermal performance of complex products –Harmonized standards and rating procedures –Tools, Data- basis for ACTION Support from institutions and government Support from trade associations and other relevant public/private organizations

56. IMPROVE STANDARDIZATION Establish new ISO WG for windows AHG for windows established 9/2011 Unify thermal calculations under TC 163 Unify optical calculations under TC 205 Change ISO 10077 with new science Develop new ISO standard for modeling complex glazing and shading devices, Develop new standard for measuring optical properties of complex products Develop new thermal measurement standard for window attachments

57. HARMONIZE RATING SYSTEMS BEST PRACTICE for MARKET IMPACTS Identify established rating systems and rating systems under current development Harmonized comparative product ratings, detailed ratings –Develops specific formats and infrastructure to allow for easy access to more detailed product information Harmonize labeling systems? Market-based Programs –Assess global programs –Share best practice –Coordinate global activity

58. Saving the Planet with High Performance Windows and Shading Systems Improve Occupant Comfort, Satisfaction and Performance Add Value, Reduce Operating Costs Reduce Energy, Greenhouse Gas Emissions Occupant Building Owner Planet