Building-Integrated Photovoltaic Designs for Commercial and Institutional Structures a Sourcebook for Architects Patrina Eiffert, Ph.D

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Building-Integrated Photovoltaic Designs for Commercial and Institutional Structures A Sourcebook for Architects Patrina Eiffert, Ph.D. Gregory J. Kiss Acknowledgements Building-Integrated Photovoltaics for Commercial and Institutional Structures: A Sourcebook for Architects and Engineers was prepared for the U.S. Department of Energy's (DOE's) Office of Power Technologies, Photovoltaics Division, and the Federal Energy Management Program. It was written by Patrina Eiffert, Ph.D., of the Deployment Facilitation Center at DOE’s National Renewable Energy Laboratory (NREL) and Gregory J. Kiss of Kiss + Cathcart Architects.

The authors would like to acknowledge the valuable contributions of Sheila Hayter, P.E., Andy Walker, Ph.D., P.E., and Jeff Wiechman of NREL, and Anne Sprunt Crawley, Dru Crawley, Robert Hassett, Robert Martin, and Jim Rannels of DOE. They would also like to thank all those who provided the detailed design briefs, including Melinda Humphry Becker of the Smithsonian Institution, Stephen Meder of the University of Hawaii, John Goldsmith of Pilkington Solar International, Bob Parkins of the Western Area Power Administration, Steve Coonen of Atlantis, Dan Shugar of Powerlight Co., Stephen Strong and Bevan Walker of Solar Design Associates, Captain Michael K. Loose, Commanding Officer, Navy Public Works Center at Pearl Harbor, Art Seki of Hawaiian Electric Co., Roman Piaskoski of the U.S. General Services Administration, Neall Digert, Ph.D., of Architectural Energy Corporation, and Moneer Azzam of ASE Americas, Inc.

In addition, the authors would like to thank Tony Schoen, Deo Prasad, Peter Toggweiler, Henrik Sorensen, and all the other international experts from the International Energy Agency’s PV Power Systems Program, TASK VII, for their support and contributions.

Thanks also are due to staff members of Kiss + Cathcart and NREL for their assistance in preparing this report. In particular, we would like to acknowledge the contributions of Petia Morozov and Kimbro Frutiger of Kiss + Cathcart, and Riley McManus, student intern, Paula Pitchford, and Susan Sczepanski of NREL.

On the cover: Architect’s rendering of the HEW Customer Center in Hamburg, Germany, showing how a new skin of photovoltaic panels is to be draped over its facade and forecourt (architects: Kiss + Carthcart, New York, and Sommer & Partner, Berlin).

Building-Integrated Photovoltaics for Commercial and Institutional Structures Contents Introduction ...... 2 Design Briefs 4 Times Square ...... 4 Thoreau Center for Sustainability ...... 7 National Air and Space Museum ...... 11 Ford Island ...... 19 Western Area Power Administration ...... 24 Photovoltaic Manufacturing Facility ...... 28 Yosemite Transit Shelters ...... 34 Sun Microsystems Clock Tower ...... 36 State University of New York, Albany ...... 38 Navajo Nation Outdoor Solar Classroom ...... 40 General Services Administration, Williams Building ...... 42 Academy of Further Education ...... 45 Discovery Science Center ...... 48 Solar Sunflowers ...... 50 Ijsselstein Row Houses ...... 52 Denver Federal Courthouse ...... 54 BIPV Basics ...... 58 BIPV Terminology ...... 69 Bibliography ...... 70 Appendix A: International Activities ...... 71 Appendix B: Contacts for International Energy Agency Photovoltaic Power Systems Task VII—Photovoltaics in the Built Environment ...... 77 Appendix C: Design Tools ...... 78 About the Authors ...... 88

Building-Integrated Photovoltaics for Commercial and Institutional Structures 1 Introduction Building-integrated photovoltaic (BIPV) electric power systems not only produce electricity, they are also part of the building. For example, a BIPV skylight is an integral component of the building envelope as well as a solar electric energy system that generates electricity for the building. These solar systems are thus multifunctional construction materials.

The standard element of a BIPV system is the PV module. Individual solar cells are interconnected and encapsulated on various materials to form a module. Modules are strung together in an electrical series with cables and wires to form a PV array. Direct or diffuse light (usually sunlight) shining on the solar cells induces the photovoltaic effect, generating unregulated DC electric power. This DC power can be used, stored in a battery system, or fed into an inverter that transforms and synchronizes the power into AC electricity. The electricity can be used in the building or exported to a utility company through a grid interconnection.

A wide variety of BIPV systems are available in today's markets. Most of them can be grouped into two main categories: facade systems and roofing systems. Facade systems include curtain wall products, spandrel panels, and glazings. Roofing systems include tiles, shingles, standing seam products, and skylights. This sourcebook illustrates how PV modules can be designed as aesthetically integrated building components (such as awnings) and as entire structures (such as bus shelters). BIPV is sometimes the optimal method of installing renewable energy systems in urban, built-up areas where undeveloped land is both scarce and expensive.

The fundamental first step in any BIPV application is to maximize energy efficiency within the building’s energy demand or load. This way, the entire energy system can be optimized. Holistically designed BIPV systems will reduce a building’s energy demand from the electric utility grid while generating electricity on site and performing as the weathering skin of the building. Roof and wall systems can provide R-value to diminish undesired thermal transference. Windows, skylights, and facade shelves can be designed to increase daylighting opportunities in interior spaces. PV awnings can be designed to reduce unwanted glare and heat gain. This integrated approach, which brings together energy conservation, energy efficiency, building envelope design, and PV technology and placement, maximizes energy savings and makes the most of opportunities to use BIPV systems.

It is noteworthy that half the BIPV systems described in this book are on Federal buildings. This is not surprising, however, when we consider these factors: (1) the U.S. government, with more than half a million facilities, is the largest energy consumer in the world, and (2) the U.S. Department of Energy (DOE) has been directed to lead Federal agencies in an aggressive effort to meet the government’s energy-efficiency goals. DOE does this by helping Federal energy managers identify and purchase the best energy-saving products available, by working to increase the number and quality of energy projects, and by facilitating effective project partnerships among agencies, utilities, the private sector, and the states.

2 Building-Integrated Photovoltaics for Commercial and Institutional Structures Because it owns or operates so many facilities, the U.S. government has an enormous number of opportunities to save energy and reduce energy costs. Therefore, the Federal Energy Management Program (FEMP) in DOE has been directed to help agencies reduce energy costs, increase their energy efficiency, use more renewable energy, and conserve water. FEMP's three major work areas are (1) project financing; (2) technical guidance and assistance; and (3) planning, reporting, and evaluation.

To help agencies reach their energy-reduction goals, FEMP’s SAVEnergy Audit Program identifies cost-effective energy efficiency, renewable energy, and water conservation measures that can be obtained either through Federal agency appropriations or alternative financing. FEMP's national, technology-specific performance contracts help implement cutting-edge solar and other renewable energy technologies. In addition, FEMP trains facility managers and showcases cost-effective applications. FEMP staff also identify Federal market opportunities and work with procurement organizations to help them aggregate purchases, reduce costs, and expand markets.

All these activities ultimately benefit the nation by reducing building energy costs, saving taxpayers money, and leveraging program funding. FEMP’s activities also serve to expand the marketplace for new energy-efficiency and renewable energy technologies, reduce pollution, promote environmentally sound building design and operation, and set a good example for state and local governments and the private sector.

This sourcebook presents several design briefs that illustrate how BIPV products can be integrated successfully into a number of structures. It also contains some basic information about BIPV and related product development in the United States, descriptions of some of the major software design tools, an overview of international activities related to BIPV, and a bibliography of pertinent literature.

The primary intent of this sourcebook is to provide architects and designers with useful information on BIPV systems in the enclosed design briefs. Each brief provides specific technical data about the BIPV system used, including the system’s size, weight, and efficiency as well as number of inverters required for it. This is followed by photographs and drawings of the systems along with general system descriptions, special design considerations, and mounting attachment details.

As more and more architects and designers gain experience in integrating photovoltaic systems into the built environment, this relatively new technology will begin to blend almost invisibly into the nation’s urban and rural landscapes. This will happen as BIPV continues to demonstrate a commercially preferable, environmentally benign, aesthetically pleasing way of generating electricity for commercial, institutional, and many other kinds of buildings.

Building-Integrated Photovoltaics for Commercial and Institutional Structures 3 4 Times Square

Location: Broadway and 42nd Street, New York City, New York Owner: Durst Corporation Date Completed: September 1999 Architect & Designer: Fox & Fowle Architects, building architects; Kiss + Cathcart Architects, PV system designers PV Structural Engineers: FTL/Happold Electrical Engineers: Engineers NY Tradesmen Required: PV glazing done by shop labor at curtain wall fabricator Applicable Building Codes: New York City Building Code Applicable Electric Codes: New York City Electrical Code and National Electric Code PV Product: Custom-sized BIPV glass laminate Size: 14 kWp Projected System Electrical Output: 13,800 kWh/yr Gross PV Surface Area: 3,095 ft2 PV Weight: 13.5 lb/ft2 PV Cell Type: Amorphous silicon PV Module Efficiency: 6% PV Module Manufacturer: Energy Photovotaics, Inc. Inverter Number and Size: Three inverters; two 6 kW (Omnion Corp.), one 4 kW (Trace Engineering) Inverter Manufacturers: Omnion Corp. and Trace Engineering Interconnection: Utility-Grid-Connected design briefs design Kiss +Architects/PIX08458 Cathcart,

Close-up view of curtain wall illustrates that BIPV panels (dark panels) can be mounted in exactly the same way as conventional glazing (lighter panels).

4 design briefs: 4 Times Square Description The tallest skyscraper built in New York City in the 1990s, this 48-story office tower at Broadway and 42nd Street is a some- what unusual but impressive way to demonstrate "green" technologies. Its developers, the Durst Organization, want to show that a wide range of healthy building and energy efficiency strategies can and should be incorporated into real Kiss +Architects/PIX06457 Cathcart, estate practices. Kiss + Cathcart, Architects, are consultants for the building tower’s state-of-the- art, thin-film BIPV system. Working in collaboration with Fox and Fowle, architects for the base building, Kiss + Cathcart have designed the BIPV system to function as an integral part of the tower's curtain wall. This dual use makes it one of the most economical solar arrays ever installed in an urban area. Energy Photovoltaics of Princeton, New Jersey, BIPV panels have been developed the custom PV modules to integrated into the meet rigorous aesthetic, structural, and curtain wall instead of electrical criteria. conventional glass Traditionally, solar technologies have spandrel panels on the been considered economical only in 37th through the 43rd remote areas far from power grids or in floor. areas with an unusually high amount of sunlight. Advances in PV efficiency are overturning these assumptions, allowing solar electricity to be generated cost- effectively even in the heart of the city. In fact, PV is the most practical means of generating renewable electricity in an urban environment. Further, BIPV can be directly substituted for other cladding materials, at a lower material cost than the stone and metal it replaces. As the Kiss +Architects/PIX08460 Cathcart, first major commercial application of BIPV in the United States, 4 Times Square points the way to large-scale production of solar electricity at the point of greatest use. The next major market for PV may well be cities like New York that have both high electricity costs and high-quality buildings. Special Design Considerations The south and east facades of the 37th through the 43rd floor were designated as the sites for the photovoltaic "skin." The custom-made BIPV BIPV was incorporated into the design panels are visible in this after the tower’s general appearance sidewalk view from had already been decided upon, so the Broadway. design briefs: 4 Times Square 5 installation was made to harmonize with the established design concept. PV System Configuration The PV modules replace conventional spandrel glass in the south and east facades. There are four different sizes of modules, and they correspond to the spandrel sizes established earlier in the

design process. Kiss +Architects/PIX06458 Cathcart, PV Module Mounting and Attachment Details The PV modules are attached to the building structure in exactly the same way that standard glass is attached. The glass units are attached with structural silicone adhesive around the back edge to an aluminum frame. An additional silicone bead is inserted between the edges of adjacent panels as a water seal. There is a separate electrical system for each facade. Each system consists of two subsystems, feeding two 6-kW inverters and one 4-kW inverter. The larger inverters serve the two large-sized PV modules, which have electrical characteristics that are different from those of the smaller ones. Using multiple inverters enables the system to perform more efficiently. The inverters are located in a single electrical closet at the core of the building. The AC output of the inverters is transformed from 120 V to 480 V before being fed into the main electrical riser.

4 Times Square during construction

6 design briefs: 4 Times Square design briefs Presidio Presidio National Park, Building 1016 Thoreau Center for Sustainability Applicable Electric Codes: Applicable Building Codes: Tradesmen Required: Structural and Electrical Engineers: Architect & Designer: Date Completed: Owner: Location: design briefs: Interconnection: Inverter Manufacturer and Model: Inverter Size: PV Module Manufacturer: PV Efficiency: PV Cell Type: PV Weight: Gross PV Surface Area: Projected System Electrical Output: Size: PV Product: Thoreau Center for Sustainability Utility-Grid-Connected Trace Engineering Model 4048 4 kW Solar Building Systems, Atlantis Energy 11% cell, 7% module Polycrystalline silicon 8 lb/ft 215 ft 716.4 kWh/yr/AC 1.25 kWp Roof-integrated, translucent glass-laminate skylight National Electric Code California structural and seismic codes Glaziers Equity Builders Tanner, StacyLeddy, Maytum, May 1996 U.S. Department of Interior, National Park Service Presidio National Park, Building 1016, San Francisco, California 2 2 National Park. Thoreau Center in Presidio skylighted of entryway the into a Federal building is the integrating photovoltaics The first application for 7

Atlantis Energy, Inc./PIX04779 Description The Greening of the Presidio demonstrates the impact of successful partnerships between the private and public sector. The Thoreau Center for Sustain- ability is a historic building, located in the National Historic Landmark District of the Presidio in San Francisco, California. The goal of transforming this historic building into an environmentally responsive structure produced an opportunity to apply Lawrence Berkeley Laboratory/PIX01052 principles of sustainable design and architecture and educate the public about them. Within this building rehabilitation project, materials selected for the renova- tion included recycled textile materials, recycled aluminum, recycled newsprint, recycled glass, and wood grown and harvested sustainably. The environmentally friendly strategy included reducing energy consumption through a Demand Side Management The PV arrays produce electricity and serve as a daylighting design (DSM) Program with the local utility com- element. pany, PG&E. The building has a highly efficient direct/indirect lighting system with provided by the utility, thereby conserving project were custom-manufactured by translucent office panels to allow inner fossil fuels and reducing pollution. Atlantis Energy to meet the esthetic zones to borrow daylight from the perime- Converting the DC electricity to AC, the requirements of the architect. The square, ter. The building is heated by an efficient system can produce about 1300 watts polycrystalline PV cells are spaced far modular boiler and is cooled by natural during periods of full sun. The system enough apart from one another to permit ventilation. The BIPV system is a highly is fully automatic and requires virtually daylighting and provide pleasant shad- visible sustainable building feature. The no maintenance. Like other PV systems, ows that fall within the space. The amount demonstration of this power system by it has no moving parts, so this solar of daylight and heat transfer through DOE FEMP, the National Renewable generating system provides clean, quiet, these panels was considered in determin- Energy Laboratory (NREL), and numerous dependable electricity. ing the lighting and HVAC requirements private-sector partners illustrates that for the space. The panels themselves The entry area into the Thoreau Center is BIPV is a technically and economically were constructed to be installed in a stan- a rectangular space with a roof sloping valuable architectural element for dard overhead glazing system framework. designers. slightly to the east and west. The roof is constructed entirely of overhead glazing, The system is installed above seismic- The skylit entryway of the Thoreau Center similar to a large skylight. PV cells are code-approved skylight glazing. The day- for Sustainability at Presidio National laminated onto the 200 square feet of lighting and solar gains through the PV Park was the first demonstration in the available overhead glazing to produce modules mounted above the skylight sys- United States of the integration of photo- approximately 1.25 kW of electricity under tem do affect the building lighting and voltaics into a federal building. Laminated standard operating conditions. The PV- HVAC loads, but the modules do not also to the skylight glass are photovoltaic cells produced DC electric power is converted serve as the weathering skin of this build- that produce electricity and also serve to high-quality AC by a power-conditioning ing envelope. Originally, the design called as a shading and daylighting design ele- unit (inverter). After it is converted, the for the PV modules to replace the skylight ment. Atlantis Energy provided custom- power enters the building to be consumed units. But during design approval, local manufactured PV panels and the system by the building’s electrical loads. building code authorities were uncertain design and integration for this project. whether the modules could meet seismic The firm was joined by construction Special Design Considerations code requirements. So the alternative specialists who made it possible to Design and construction issues for the design, stacking the skylights and the transform this historic building into an relatively small Thoreau Center system modules, was used instead. environmentally responsive structure. were similar in many ways to issues involved with designing and constructing To ensure that the glazing used in manu- The solar electricity generated in the much larger systems. The panels for this facturing the PV panels was acceptable PV system in the skylight offsets power according to Uniform Building Codes 8 design briefs: Thoreau Center for Sustainability 02527226m

This schematic drawing shows how the PV modules were attached above the conventional skylight glazing.

design briefs: Thoreau Center for Sustainability 9 02527228m

This drawing shows how the photovoltaic skylight array was arranged. The total array area is 20.6 square meters.

(UBC), building code issues were an ethylene-vinyl acetate coating, a connected in series to feed the sine-wave addressed. Special arrangements were translucent Tedlar-coated polyester back- inverter, which is configured to 48 V and made with the local electrical utility to sheet, and two sealed and potted junction rated at 4,000 W capacity. ensure that the grid-tied system would boxes with a double pole plug connector. meet safety requirements. Finally, The PV cells are laminated in a 6-cell x 6- PV Module Mounting and installing the system required coordina- cell matrix. The minimum spacing Attachment Details tion between the panel supplier, electri- between cells is 1.25 cm (1/2 in.). The Structural upgrades were made to accom- cian, glass installer, and Presidio facilities dimension of each module is 81 cm x modate the additional weight of the PV personnel. 94 cm (32 in. x 37 in). The gross area of system. These added about $900 to the the entire structure is 18.8 m2 (200 ft2). PV System Configuration total cost, for structural components. The BIPV glazing system consists of 24 PV The power produced by the system is con- glass laminates. The spacing of the cells verted to high-quality AC electricity and within the modules allows approximately supplements power supplied to the build- 17% of the sunlight into the entryway, ing by the utility. The system is rated at reducing the need for electric lights. The 1.25 kW. Each of the 24 PV modules gen- modules consist of 6-mm Solarphire erates 8.5 V of DC power at approximately glass, 36 polycrystalline silicon PV cells, 5.5 amps. Six modules per sub-array are

10 design briefs: Thoreau Center for Sustainability design briefs National Air and Space Museum Interconnection: Model: Inverter Manufacturer & Inverter Number and Size: PV Module Manufacturer: PV Efficiency: PV Cell Type: PV Weight: Surface Area: Gross PV Projected System Electrical Output: Size: PV Product: Applicable Electric Codes: Applicable Building Codes: Tradesmen Required: Electrical Engineers: Structural Engineers: Architect & Designer: Date Completed: Owner: Location: design briefs: solar solar cells. films and polycrystalline such technologies, as thin different BIPV systems and will entryway demonstrate The BIPV installations at the National Air and Space Museum Smithsonian Institution Dulles Center, Washington, DC Utility-Grid-Connected To be determined To be determined canopy system Energy Photovoltaics, Inc., for the Systems will range from 5% to 12% Polycrystalline cells, amorphous silicon film for various systems 5 lb/ft 223 m 15.12 kWh for the canopy system curtain wall, facades, and canopy To be determined for BIPV Various systems BIPV National Electric Code BOCA, Metropolitan Washington Airport Authority Building tradesmen N/A N/A Satish Shah, Speigel, Zamel, & Shah, Inc. HOK, Building Architects; Kiss + Cathcart Architects, PV System Designers; Construction begun in 2000, scheduled for completion in 2003 2 2 for the canopy system for the canopy system PV CurtainWall PV Canopy Project Overview: Axonometric 02527218m 11 Plan view of BIPV installation at entry areas

Description Kiss + Cathcart, Architects, are under core mission is to protect the nation’s contract to the National Renewable collection of aviation and space-flight- The National Air & Space Museum Energy Laboratory as architectural- related artifacts. It will also house the (NASM) of the Smithsonian Institution is photovoltaic consultants to the preservation and restoration workshops one of the most-visited museums in the Smithsonian Institution. Working with of the Air and Space Museum. world. However, its current building on the Smithsonian and HOK Architects, the Mall in Washington, D.C., can accom- The center’s design includes a large, Kiss + Cathcart is identifying suitable modate only a fraction of NASM’s collec- hangar-style main exhibition space that areas for BIPV, selecting appropriate tion of historical air- and spacecraft. will allow visitors to view the collections technologies, and designing the BIPV Therefore, a much larger expansion facil- from two mezzanines as well as from systems. For DOE FEMP, a partner in the ity is planned for a site adjacent to Dulles ground level. It is estimated that more project, a primary goal is to demonstrate Airport. Since the new facility will exhibit than 3 million people will visit the center the widest possible range of BIPV applica- technologies derived from space explo- annually to view aircraft, spacecraft, and tions and technologies in one building. ration, the use of solar energy, which has related objects of historic significance, Construction should begin in 2000. powered satellites and space stations many of which are too large to display at since the 1950s, is especially fitting for The NASM Dulles Center will serve as the National Air and Space Museum in this new building. an exhibit and education facility. Its Washington, D.C. The facility will set new

12 design briefs: National Air and Space Museum The south- and west-facing facades of the entry hall will be glazed with polycrystalline glass laminates.

design briefs: National Air and Space Museum 13 BIPV Canopy - section 1:60

Canopy: Structural Details

BIPV Canopy detail 1:10 Thin-film BIPV glass laminates will function 02527219m as the canopy. standards for collections management met: (1) reduce the amount of energy visitors attention on the PV. Labels, and the display of large, 20th-century required from the power grid, especially exhibit material, and museum tour staff functional objects. during peak times, and thus conserve could further highlight the PV arrays and energy and save operational funds, and call attention to the energy savings being Smithsonian staff are evaluating the inte- (2) demonstrate the use of PV in a highly realized. PV would also be used to power gration of a number of grid-connected visible context in a much-visited Federal some exhibit material exclusively. The BIPV systems into the building. The NASM facility. related exhibit materials could highlight Dulles Center will be a very large structure the many connections between PV and (740,000 ft2), with commensurate energy Five BIPV subsystems could be demon- the field of space exploration and utiliza- and water requirements. As part of its strated at the new NASM facility, including tion, as well as today’s construction and educational mission, the museum plans the south wall and skylight of the entry building industry. to exhibit hardware that points to the "fuselage," the roof of the restoration historic use of photovoltaic (PV) power hangar and space shuttle hangar, the systems in space; the museum would facade of the observation tower, and also like to demonstrate how that tech- awning canopies. The entry fuselage nology can be used today in terrestrial figure clerestory windows will be a highly applications such as BIPV. To this end, visible way of demonstrating PV to visi- the Smithsonian is evaluating the highly tors approaching the center. Once in the visible application of BIPV at this facility entryway, visitors would also see the to meet a portion of its energy require- patterns of shadow and light the fritted ments. In this way, two objectives will be glass creates on the floor, thus focusing 14 design briefs: National Air and Space Museum Fuselage detail illustrates patterns of polycrystalline glazing.

design briefs: National Air and Space Museum 15 Curtain wall details indicate how mullion channels will act as electrical conduits.

16 design briefs: National Air and Space Museum The canopy plan and perspective demonstrate how shading and power output are combined in one architectural expression.

design briefs: National Air and Space Museum 17 Curtain walls typically will be 16 polycrystalline solar cells per panel, laminated between two clear glass panes.

18 design briefs: National Air and Space Museum design briefs Building 44, Pearl Harbor Naval Station Ford Island design briefs: Tradesmen Required: Electrical Engineers: Structural Engineers: Architect & Designer: Date Completed: Owner: Location: Interconnection: Inverter Manufacturer and Model: Inverter Number and Size: PV Module Manufacturer: PV Module Efficiency: PV Cell Type: PV Weight: Gross PV Surface Area: Projected System Electrical Output Size PV Product: Applicable Electric Codes: Applicable Building Codes: represent the photovoltaic standing-seam metal roofing material. This illustration is a view of the building from the corner; southwest the dark areas 2.8 kW DC : Ford Island : 9,720 kWh per month : Utility-Grid-Connected Trace SW 4048PV One, 4-kW Uni-Solar 5%-6% Multijunction amorphous silicon 4 lb/ft 571 ft Integrated standing seam metal roof National Electric Code Uniform Building Code Roofers, electrical contractors Hawaiian Electric Co.; Peter Shackelford, Renewable Energy Services, Inc., system integrator Hawaiian Electric Co. Architecture Victor Olgyay, Fred Creager, and Stephen Meder, University of Hawaii, School of September 1999 U.S. Navy, Department of Defense, and Hawaiian Electric Company Honolulu, Hawaii 2 2 , with the roof

02527213m 19 02527214m

In this illustration, the dark areas represent amorphous silicon laminates on standing seam metal roofing panels.

Description PV system, the McElroy metal substrate, Special Design Considerations and the Trace inverter in a tropical marine A partnership consisting of the U.S. Navy, The context of this project is the naval environment will provide valuable perfor- Hawaiian Electric Co. (HECO), the industrial site at Pearl Harbor Naval mance information to guide the future University of Hawaii, the U.S. DOE Federal Base.The site contained a 90 ft x 52 ft development and use of these products. Energy Management Program (FEMP), (27.4 m x 15.8 m) open-wall boathouse and the Utility PhotoVoltaic Group (UPVG) The total cost of this project was $92,000. structure. The existing roof of the struc- was created in order to design and install This included design, procurement, roof ture was made of box rib metal on trusses a 2-kW, grid-intertied, BIPV retrofit sys- removal and BIPV installation, and a year (Figure 2) in gable form, divided longitudi- tem using the Uni-Solar standing seam of monitoring. nally on its east-west axis. The south metal roofing product and to monitor its performance for one year. The University of Hawaii School of Architecture designed and administered the project and a local PIX08475 utility, HECO, funded it. Additional construction cost support was supplied by FEMP, NREL, and the Navy. The utility and the Navy determined the site, and the installation date was scheduled for the third quarter of 1998 (Figure 1). HECO was designated to be the client for the first year, after which the Navy will assume ownership of the system. The tropical location (21° North) and the site’s microclimate make it an ideal location for PV installations. Project planners expected an annual daily average of 5.4 peak sun hours and 20 to 25 in. (57 cm) of annual rainfall. This project, at this particular site, will also be testing the limits of the products used in the installation. Monitoring the performance of the The array in mid-installation is shaded only by cloud cover.

20 design briefs: Ford Island Uni-Solar product; unless new PV-to- metal laminating processes are developed, this product will be substantially limited in metal roofing applications. Joining the panels to extend their length not only increases material and labor costs, it also provides opportunities for water penetration and corrosion. The "galvalum" coating is cut away every- where the panel is modified. This exposes the steel of the standing seam panel to the marine environment. Therefore, McElroy, Uni-Solar’s metal roof supplier, will not warranty the product for marine applications. In addition, to match the paint of the existing structure, McElroy required a minimum order to custom-paint the new roof panels. Therefore, about one-third more roofing panels had to be purchased than were needed, and this increased the overall project cost. The extra panels turned out to be useful, however, since many were damaged during transport to Hawaii. The part of the roof to be retrofitted spans a dock area below. This presented staging challenges for the roofing and electrical contractors. Along with restricted access to the military base and the need to take a bridge to the site, the location of the roof added to the complexity and costs of the project. And the harsh marine environment could have a corrosive effect on the array and its components. PV System Configuration This illustration shows how the notched BIPV standing-seam components The system is rated at 2.175 kW AC overlap the regular roofing panels. (2.8 kW DC). The estimated system output is 9,720 kWh per month. The building is not independently metered. It is fed by slope provides a 90 ft x 26 ft (27.4 m x provide is 20 ft (6.09 m) and the required the Pearl Harbor grid, to which HECO sup- 7.9 m) surface at a 5° incline. This half run is 26+ ft (8 m). This shortfall required plies power. The estimated demand of the of the roof measured approximately overlapped joints to be used on the ends building is about 12000 kWh per month. 2,340 ft2 (217 m2). The box rib roofing of the panels and additional purlines The energy generated by the PV system was removed from the entire south-facing to be welded for support. Full-length, will feed but not meet the average loads slope, and new standing seam pans, standing-seam panels and non-PV panels of this building. including 24 of the Uni-Solar SSR 120 were set in an alternating pattern with PV Module Mounting and photovoltaic standing seam panels, the PV modules. This arrangement replaced the original roofing. allowed the full-length pans to add Attachment Details strength over the required lap joint of Integrated connection follows standard Integrating the new metal roofing with the shorter PV units. metal seam roof attachment process. the existing roof posed several design Notched PV panels are secured to non-PV and construction challenges. In addition, The length limitation of the Uni-Solar panels with metal fasteners. the longest panel that Uni-Solar could panels was a design deficiency of the design briefs: Ford Island 21 PIX08476 PIX08477

Workers install short lapped roofing pans at BIPV Additional electrical junction boxes were required over module sections. potted terminals and raceways at the ridge, before the ridge cap was installed. PIX08478 PIX08480

Junction box at ridge, viewed from below Junction box at ridge, viewed from above

22 design briefs: Ford Island 02527289m

The part of the roof containing BIPV spans a dock area, as shown in this illustration.

design briefs: Ford Island 23 design briefs Interconnection: Inverter Manufacturer: Inverter Number and Size: PV Module Manufacturer: PV Efficiency: PV Cell Type: PV Weight: Gross PV Surface Area: Projected System Electrical Output: Size: PV Product: Applicable Electric Codes: Applicable Building Codes: Tradesmen Required: Electrical Engineers: Structural Engineers: System Integrator: Architect & Designer: Date Completed: Owner: Location: Phase Phase I Elverta Maintenance Facility, I Phases and II Western Area Power Administration 4design briefs: 24 Utility-Grid-Connected Omnion Corp. 8 inverters, 6 kW each Solarex 12% Polycrystalline silicon 4 lb/ft 5,400 ft 70,000 kWh/year 40 kW DC roof tiles PowerGuard™ BIPV National Electric Code Standard California building codes Roofers, electrical contractors DOE Western Area Power Administration DOE Western Area Power Administration PowerLight Corporation DOE Western Area Power Administration, PowerLight Corporation May 1996 U.S. of Department Energy (DOE) Western Area Power Administration Elverta, California 2 2 40-kW system installed in 1996. A 38-kW BIPV system supplements a Phase II Western Area Power Administration Phase I

PIX08451 Description Staff in the Department of Energy’s Western Area Power Administration PIX08450 Sierra Nevada Region (SNR) have had two main goals for SNR's photovoltaic (PV) program: (1) promote PV systems as a renewable energy resource, and (2) do so in a cost-effective manner. In support of these goals, SNR has incorporated PV panels into the roofs of buildings in Elverta and Folsom, California. The building-integrated systems will repay invest- ments in them by extending roof lives, reducing maintenance costs, generating electric power, and reducing the buildings' cooling requirements. In Phase I, a 40-kW building-integrated photovoltaic system was installed at SNR's Elverta Maintenance Facility. The Sacramento Municipal Utility District A PowerLight rooftop PV system is installed on Western’s facility in (SMUD) funded the PowerLight Corp. Elverta, California. PowerGuard® system, while Western contributed funds equivalent to the cost of replacing the facility roof. Funding was also provided by the Utility Photovoltaic

Group (UPVG) through TEAM-UP, with PIX08452 support from the U.S. Department of Energy. With a power capacity of 40 kW peak DC and an annual energy output of more than 70,000 kWh/year, the PV systems have significant environmental benefits. Phase I prevents the emission of 2,300 tons of carbon dioxide, 8.7 tons of nitrogen oxides and 16.4 tons of sulfur dioxides; these emissions would be the result if fossil fuels were burned to generate the same amount of electricity. Because this system is designed to have a life expectancy of 20 years, the cumula- A view of the rooftop of the Elverta facility after the PV system installation. tive benefits for the environment are many. for greater annual energy production. In PV System Configuration Special Design Considerations addition to generating clean renewable A 40-kW PowerGuard building-integrated PowerGuard PV tiles were used to reroof energy, the lightweight system provides PV system was installed at the Elverta the building, saving on the cost of con- R10 roof insulation for improved building Maintenance Facility in Western's Sierra ventional roofing material. The patented comfort and membrane protection for Nevada Region to function as both a roof PowerGuard tiles incorporate high-effi- extended roof life. Installation took only and solar electric photovoltaic (PV) power ciency polycrystalline silicon cells from 7 days to complete once the building's plant. Phase I modules were installed in Solarex. Site conditions were favorable old roof was replaced with a new single- parallel strings containing 56 modules per for this sytem: 38° latitude; a dry, sunny ply membrane roof. string (7 series, 8 parallel). climate throughout most of the year; and no shading. The system features horizontal tiles and tiles with an 8° southerly tilt design briefs: Western Area Power Administration 25 02527230m The temperature curves show how the PV-integrated roof compares with various roofs without solar electric systems. Roof-integrated PV with integral insulation reduces a building’s heat load as much as 23°C. The measurements were derived from sensors placed in representative roof specimens.

PV Module Mounting and Attachment Details PIX08453 The panels are designed to interlock using a tongue-and-groove assembly. Panels with 3/8-in. concrete topping, instead of PV modules, are set among the PV panels to allow working access throughout the roof. Along the edges of the PVarray, a steel ribbon links the modules together, in order to connect everything structurally.

Workers carry PV modules with attached foam backing in preparation for rooftop mounting. Smaller panels with concrete topping were also installed as a walking surface.

26 design briefs: Western Area Power Administration Phase II Location: Elverta, California Owner: U.S. Department of Energy (DOE) Western Area Power Administration Date Completed: June 1998 Architect & Designer: DOE Western Area Power Administration, PowerLight Corporation System Integrator: PowerLight Corporation Structural Engineers: DOE Western Area Power Administration Electrical Engineers: DOE Western Area Power Administration Tradesmen Required: Electrical and building contractors Applicable Building Codes: Standard California building codes Applicable Electric Codes: National Electric Code PV Product: PowerGuard™ BIPVroof tiles Size (kWp): 38 kW DC Projected System Electrical Output: 67,500 kWh/year Gross PV Surface Area: 9,900 ft2 PV Weight: 5 lb/ft2 PV Cell Type: Thin-film amorphous silicon PV Efficiency: 4%-5% Phase I PV Module Manufacturer: Solarex (762 modules) and APS (264 modules) Inverter Number and Size: One 32-kW AC Inverter Manufacturer and Model: Trace Technologies Interconnection: Utility-Grid-Connected Phase II

Description Special Design Considerations produce 43 watts each. The APS modules were installed in 22 parallel strings with This 38-kW BIPV system supplements the The flush roof design provides excellent 12 modules in series per string. The APS Phase I system. Both systems completely insulation as well as electricity, as shown modules produce 22 watts each. cover the Elverta roof and are the largest in the graph comparing roof temperature PV application of its kind in the United data. PV Module Mounting and States. Phase II is totally funded and Attachment Details owned by Western. The PV systems utilize PV System Configuration thin-film amorphous silicon technology. The Solarex modules were installed in Same as those for Phase I. The DC output from the PV modules is 254 parallel strings, with three Solarex converted to 240 V AC by means of a modules in series per string. The modules custom-built 32-kW Trace inverter, and then stepped up to 480 V, three-phase AC by a 45-kVA transformer for direct Solar Electric Roofing Panel connection to the building's service Membrane panel. Besides replacing grid power, the Styrofoam® Powerlight system protects the roof Insulation membrane, which extends its life. The roof system also provides R10 insulation to reduce cooling and heating loads, thereby decreasing energy consumption.

Substrate Roof Deck 02527234m

The illustration shows how the layers in the roofs provide above-average insulation as well as a good base for the PowerGuard PV system. design briefs: Western Area Power Administration 27 design briefs Photovoltaic Manufacturing Facility 8design briefs: 28 PV Product: Applicable Electric Codes: Applicable Building Codes: Tradesmen Required: Electrical Engineers: Structural Engineers: Architect & Designer: Date Completed: Owner: Location: Interconnection: Interconnection: Inverter Manufacturer: Inverter Number and Size: PV Module Manufacturer: PV Efficiency: PV Cell Type: PV Weight: Gross PV Surface Area: Projected System Electrical Output: Size: canopy that runs the length of the building. Views looking north (top) and south show how BIPV is integrated into both the facade and the PSolar BP Fairfield, California Utility-Grid-Connected Omnion Corporation 6 kW APS 5% Amorphous silicon 3 lb/ft 1,975 ft 7.9 kW 9.5 kWp Glass laminates as curtain wall spandrel, skylight, and awning National Electric Code BOCA and California Title 24 Glaziers, electricians Ove Arup & Partners Ove Arup & Partners Kiss Anders, Cathcart Architects 1993 2 2 Photovoltaic Manufacturing Facility

PIX08449 PIX08446 that demonstrates BIPV in a typical commercial building. The cube’s PV cladding,

PIX08447 the solar entrance canopy, and the translucent BIPV skylight provide more than enough energy to power the control center’s lighting and air-conditioning systems. The production floor and warehouse space are housed in a tilted-up concrete shell with a steel intermediate structure and a timber roof. Glass blocks embedded as large-scale "aggregate" in the outside walls provide a pattern of light in the interior during the day and on the exterior at night. Mechanical service elements are contained in a low, steel-framed structure on the north side of the building. The entry court is paved in a pattern of tinted concrete and uplighting that represents an abstracted diagram of solar energy generation. Special Design Considerations In addition to providing a working product development test bed for BIPV systems, the project serves an educational function for public and private groups. The lobby/reception area provides display space for products and research. A pattern cast into the paving in front of the main entry combines a sun path diagram with a representation of the photovoltaic effect at the atomic level. The control room/cube also serves an educational Interior view shows how BIPV is used with vertical and sloped

glazing. PIX08448

Description Completed in 1993, this 69,000-ft2 manufacturing facility houses a new generation of production lines tailored to thin-film PV technology. The building also incorporates into its design several applications of thin-film solar modules that are proto- types of BIPV products. The heart of the project is a 22.5-ft-high BIPV glass cube containing the factory’s control center and visitor facilities. This cube is perched on the second floor, and half of it is outside of the manufacturing building, emphasizing its status as an This office interior view demonstrates the quality of light transmitted independent element and a prototype by the approximately 5% translucent BIPV panel skylight.

design briefs: Photovoltaic Manufacturing Facility 29 02527210m Parapet beyond Built-up roofing, min. slope 1/4" per 1'-0" toWood drain frame roof - See structural dwgs Glu-lam beam Braced frame beyond glass Aluminum frame Vision glass GWB Steel column Wainscot Concrete base @ column Concrete slab Spread footing beyond - see structural dwgs Steel stair beyond Expanded metal panel Steel guardrail Plastic coated wire REFER TO MECHANICAL DWGS FOR ALL MECHANICAL LOCATIONS Oriented strand board Integral duct Stainless steel panel Receptionist's booth, see sheet A39 Footing beyond Elevator pit beyond Vision glass, tempered type D typ. PV skylight Parapet beyond Built-up roofing Tapered insulation Metal deck Scupper & D.S. beyond Steel beam Aluminum curtain wall PV glass Flashing Elevator bulkhead beyond 7 A39 4 5 6 A37 A37 A37 Plywd panels 6 A16

2 A37

'41/4" 8'-4 1'-9" 2'-7" 3/4" 12'-4

D.1

2'-6" 2'-6"

5'-0" 5'-0" 5'-0" 5'-0"

2'-6" 3

A37 C C C C C C Sectional view shows office “cube” and factory.and “cube” office shows view Sectional PV awning Concrete walk Vision glass, tempered glass, type B, typ.

30 design briefs: Photovoltaic Manufacturing Facility 02527206m Axonometric NTS 6 PV panel Panel connection below Purlin below Panel wiring points typ. Light fixture below (25' O.C.) Curved Stainless panel below Vertical Stainless stiffener 381 1066.8 1828.8 914.4 East end bay (West end opposite hand) 15 381 533.4 381 152.4 152.4 PV panel Purlins Frame Bracing rods Light fixture Stainless steel awning assembly 330.2 533.4 381 406.4 508 914.4 eq. typ. PV spacing typ. PV connection point spacing 914.4 3505.2 eq. Typ. awning bay (see A06-A07 for locations) See structural drawings for frame dimensions C Awning Section 1/2" = 1'0" 1 above slab above slab 3352.8 2743.2 Typ. braced bay (see A06-A07 for locations) 14 381 1,2 A40 Awning Plan 1/2" = 1'0" 3 The PV awning provides a sunscreen. a provides awning PV The design briefs: Photovoltaic Manufacturing Facility 31 REFER TO SHT. A/20 FOR LOCATIONS OF WALL OPENINGS AT TILT-UP PANELS REFER TO MECHANICAL DWGS FOR ALL MECHANICAL LOCATIONS 8 7

7.9 7.8 7.2 7.1 6.8 6.5

PV skylight 7 Built-up roofing, min. slope 1/4" per 1'-0" to drain A37 +35'-2 1/2" Tapered insulation T.O.Cube Metal deck Steel beam

Aluminum curtain wall PV glass Plywood interior finish panels Vision glass tempered glass type D, typ. +27'-8" 7'-6" Flashing T.O.Conc. tilt-up wall

+25'-0"-26'-8" T.O.Frame varies 22'-9 1/2"

8 A37 Steel guardrail 8'-4 1/4" Expanded metal pane Plastic coated wire

+15'-0" 1'-9" T.O.Mezz. 2'-7"

9 A37 12'-4 3/4" 12'-4 3/4"

+0'-0" T.O.Slab

02527208m 1 Section looking south through cube Scale: 1/4"=1'-0"

Sectional view indicates skylight configuration and curtain-wall facade.

32 design briefs: Photovoltaic Manufacturing Facility function; a raised platform allows groups PV System Configuration nated products. The modules are installed of visitors to view the control equipment, with an insulated inner liner, which forms The PV module is a nominal 2.5 ft x 5.0 ft, and beyond it, the production line. a plenum for ventilation. Heat radiated a-Si thin-film device rated at 50 Wp stabi- Computerized monitoring equipment dis- into the curtain wall plenum is vented to lized. The PV system contains 84 full-size plays the status of the PV systems as well the outside by natural convection through modules mounted on the awning, 91 mod- as information regarding building HVAC holes drilled in the horizontal mullions. In ules installed in the curtain wall, and 8 in and lighting energy use, exterior ambient some cases, the hollow vertical mullions a skylight. The curtain wall modules are conditions, insolation, and other data. are used as ducts to direct the warm air installed in custom sizes as required by upward. Wherever possible, the PV systems are architectural conditions. The system has designed to do double duty in terms of a total capacity of 7.9 kW; because of the The skylight panels are standard modules energy management by reducing heat varying orientations of the modules, the that transmit approximately 5% of the gain while providing power. The curtain peak output is 5 kW. Despite the hot local sunlight through the laser scribe lines. wall and skylight are vented, eliminating climate, the power consumed by the cube The PV modules are supplemented by radiant heat gain from the modules and for cooling and lighting never exceeds clear glazing units to increase light trans- enhancing natural ventilation in the cube. 3.5 kW, producing a surplus of PV power mission. Another unique feature of this The awning is designed to shade the row which is directed into the main building BIPV system is that the skylight is vented of south-facing windows that open into grid. to remove heat gain from the modules. the production area and employee The awning panels are bolted through the lounge. The cube curtain wall integrates PV Module Mounting and steel tube awning structure to aluminum PV modules with vision glass in a Attachment Details channels epoxied to the encapsulating standard pressure plate curtain wall Standard PV modules are 31 in. x 61 in. glass. This is the attachment used in typi- framing system, modified to be self- but can be produced in custom sizes as cal field-mounted arrays. ventilating. The system is intended to required to fit the framing requirements of be economical and adaptable to new the curtain wall. One unique feature is construction or retrofit. that the modules are glass-to glass lami-

design briefs: Photovoltaic Manufacturing Facility 33 design briefs Yosemite Transit Shelters 4design briefs: 34 PV Product: Applicable Electrical Codes: Applicable Building Codes: Tradesmen Required: Electrical Engineers: Structural Engineers: Architect & Designer: Date Completed: Owner: Location: Interconnection: Interconnection: Inverter Manufacturer: Inverter Numbers and Size: PV Module Manufacturer: PV Efficiency: PV Cell Type: PV Weight: Gross PV Surface Area: Projected System Electrical Output: Size: locally forested lumber with BIPV panels. The transit shelter prototype makes use of both high-tech and low-tech materials, combining U.S. Department U.S. of Department Interior, National Park Service Yosemite National Park, California Optional—Grid-Connected or Stand-Alone Advanced Energy Systems 1 kW Energy Photovoltaics, Inc. 6% Amorphous silicon 3.375 lb/ft 112 ft 1.15 MWh/yr 560 Wp per transit shelter Amorphous silicon glass panels National Park Service, self-regulating National Park Service, self-regulating Standard Contractor/Carpenter and Electrician None; design overview provided by inverter manufacturer Ove Arup & Partners, Structural Engineers Kiss + Cathcart, Architects Scheduled for system completion in 2001 2 2 02527238m Yosemite Transit Shelter Description Yosemite National Park is one of the most treasured environments in the United States – and also the site of serious vehic- ular traffic congestion. The National Park Service is working to reduce traffic and pollution in Yosemite by expanding the

shuttle bus service and introducing elec- Dave Parsons, NREL/PIX00923 tric shuttle buses. This necessitates an infrastructure of combined weather shelters and information boards at the new shuttle stops. Funded by DOE FEMP, Kiss + Cathcart, Architects, is under contract to NREL to design a prototypical bus shelter incorporating BIPV panels. The park will begin installing the first of 19 new shuttle stops in the summer of 2000. The shelters that are near existing electrical lines will send the power they generate into the utility grid system serving Yosemite; the more remote shelters will have battery storage for self-sufficient night lighting. Yosemite National Park Special Design Considerations The design mandate for this project is to undesirable in terms of both appearance balance a sense of the rustic historical and material use. building style of the Yosemite Valley with the frankly technological appearance of PV System Configuration BIPV systems. The overall structure is Fourteen semitransparent, 40-W thin-film a composite of heavy timber and steel modules make up the PVsystem for each plates that serves two purposes: accom- shelter. Power is fed to a single inverter. modating heavy snow loads with mini- Some systems will be grid-connected and mum structural bulk and projecting an some will be stand-alone with batteries appearance that is rustic from a distance for backup. but clearly modern in a close-up view. The structural timbers (unmilled logs PV Module Mounting and from locally harvested cedar) are split Attachment Details in half, and the space between them is The PV roof of the shelter is not designed used for steel connections, wiring, and to be watertight like the roof of an mounting signage. The BIPV roof struc- enclosed building. Instead, it is designed ture is made of a single log cut into eight to be waterproof so that water does not separate boards. drip through the roof in normal weather A shallow (10°) tilt was chosen for the PV conditions. Therefore, the PV modules are roof. A latitude tilt of approximately 37° overlapped (shingled) slightly along the would provide the maximum annual out- center seam, and sheet metal gutters are put in an unobstructed site; however, a inserted at the seam between the rough shallower angle is better suited to wood rafters and the modules. Yosemite because of the considerable shading that occurs at low sun angles in the valleys, especially in winter. A steeper slope would also have made the shuttle stop much taller, significantly increasing structural loading and demanding a heav- ier structure. This was determined to be design briefs: Yosemite Transit Shelter 35 design briefs Sun Microsystems Clock Tower 6design briefs: 36 PV Product: Applicable Electrical Codes: Applicable Building Codes: Tradesman Required: Electrical Engineers: Structural Engineers: Architect & Designer: Date Completed: Owner: Location: Interconnection: Interconnection: Inverter Manufacturer and Model: Inverter Number and Size: PV Module Manufacturer: PV Efficiency: PV Cell Type: PV Weight: Gross PV Surface Area: Projected System Electrical Output: Size: Microsystems facility. the clock tower at Sun North-facing view of Sun Microsystems Burlington, Massachusetts Utility-Grid-Connected Omnion Power Corp. One 2.5 kWp inverter Pilkington Solar International 12.8% Americas, Inc. Polycrystalline silicon manufactured by ASE 8.3 lb/ft 827 ft 2.5 kWp 2.5 kWp curtain wall BIPV Section 620 National Electric Code Uniform Building Code Glaziers, electricians Engineering Enertech Whiting-Turner Contracting Co. HOK Architects and Americas, ASE Inc. October 1998 2 2 Sun Microsystems Clock Tower

ASE Americas, Inc./PIX07044 ASE Americas, Inc./PIX07045 ASE Americas, Inc./PIX07042

Pilkington Solar International’s East view of the clock tower shows BIPV installation. project leader, John Goldsmith, is shown with the integrated curtain wall on the south and west faces of the clock tower.

Description Special Design Considerations PV Module Mounting and ASE Americas recently provided the The PV panels were custom designed to Attachment Details design, PV panels, and electronic equip- match the dimensions of the Kawneer Eight electrically active panels were fuly ment needed to power an 85-ft high clock Series 1600 mullion system used on the wired and interconnected through an tower on Sun Microsystems' new 1 million four sides of the clock tower. They were inverter and transformer into the building ft2 campus in Burlington, Massachusetts. fabricated as dual-glazed, thermally wiring as a utility-interactive system. The architects who designed the building insulating panels with a glass-cell-glass These systems are the simplest and most included both electrically active and elec- laminate as the outer surface and a economical way to install a PV power trically inactive glass panels on four sides frosted glass sheet as the inner surface. source. There are no batteries in this type of the tower. The electrically active panels Some of the panels were required to wrap of system, since the system draws power incorporating PV modules were used on around the clock, so three different basic from the building's electrical grid. the east and west sides. A diffuse light shapes were designed with round cusps pattern washes around the edges of the cut out of the corners to match the curva- solar cells in the inside of the tower to ture of the round, 7.5-ft-diameter clock. create a soft look in the interior. The clock Two rectangular shapes were required so tower load is primarily a nighttime load. the panels were vertically arranged to Energy from the PV array goes into the match the floor levels. building by day, and the clock tower draws power at night from the building's PV System Configuration electrical grid. This could be the first use The PV modules are connected in series of dual-glazed, thermally insulated PV and feed electricity into an inverter that panels in a U.S. building structure. converts the 2.5 kW DC power to AC.

design briefs: Sun Microsystems Clock Tower 37 design briefs PV product: Applicable electrical codes: Applicable building codes: Tradesmen Required: Solar Consultant: Electrical Engineer: Architect: Date Completed: Owner: Location: Interconnection: Interconnection: Inverter Manufacturer and Model: Inverter Number and Size: PV Module Manufacturer: PV Cell Efficiency: PV Cell Type: PV Weight: Gross PV Surface Area: Project System Electrical Output: Size: State University of New York, Albany 8design briefs: 38 Management Technology Sciences and Environmental at the Center for Looking southeast State University of New York, Albany Albany, New York Utility-Grid Connected Advanced Energy Systems Micro Inverter 250 AES watt Solarex 12% Polycrystalline silicon 1.93 lb / ft 1,500 ft 19,710 kWh / yr. 15 kWp Kawneer 1600 PowerWall™ National Electric Code New York State Building Code Z97.1 and ANSI Beacon Sales Corporation, roofing contractors Solar Design Associates, Inc. Cannon Architects Cannon Architects Summer 1996 2 2 State University of New York, Albany

Gordon Schenck/PIX084 Description For the new Center for Environmental Sciences and Technology Management (CESTM) at the State University of New York in Albany, Cannon Architects developed an energy-conscious design strategy. This strategy included the integration Gordon Schenck/PIX08464 of solar electric systems into both the building and the project site as landscape elements. The building incorporates 15 kWp of custom PV modules in building- integrated sunshades that support the PV modules while reducing cooling loads and glare on the south facade. The PV modules feature module-integrated inverters. Special Design Considerations This system was the first of its kind in the United States to tie together more than 2 kW of AC modules, and the first to use the AC module platform for a sunshade. AC modules proved to be far more effective than a typical single inverter, given the different light levels on the modules over the course of a day. PV System Configuration There are two different system configurations in the CESTM solar system. The sunshade portion consists of 59 pairs of framed Solarex MSX 120 modules. Each pair is connected to its own accessible AC micro-inverter. The inverters are installed inside the building for ease of service. The landscape portion consists of 18 pairs of Solarex MSX 240 modules. An AC micro- inverter is attached to the underside of each pair. PV Mounting and Attachment Details Close-up view of photovoltaic sunshade Solarex provided framed PV modules that were modified to incorporate the AES micro-inverters. Most of the modules were mounted in an aluminum strut, creating a solar sunshade. The rest of the modules were mounted above ground, along a curved pathway at the main approach to the building. The building’s sunshades use standard extrusions from the Kawneer curtain wall system, the Kawneer 1600 PowerWallTM. This custom configuration provided structural support to the modules. design briefs: State University of New York, Albany 39 design briefs PV Product: Applicable Electrical Codes: Applicable Building Codes: Tradesmen Required: Solar Consultant: Electrical Engineer: Architect: Scheduled Completion Date: Owner: Location: Interonnection: Inverter Manufacturer: Inverter Number and Size: PV Module Manufacturer: PV Efficiency: PV Type: PV Weight: Gross PV Surface Area: Projected System Electrical Output: Size: Navajo Nation Outdoor Solar Classroom 0design briefs: 40 supported supported by timber columns in a concrete foundation. Each new BIPV structure at the Seba Dalkai School will as serve an open-air classroom Seba Dalkai Boarding School Seba Dalkai, Navajo Reservation, Arizona Stand-Alone System Trace Engineering Four 2.5 kW inverters Energy Photovoltaics, Inc. 6% Amorphous silicon 3.75 lb/ft 625 ft 5,818 kWh/yr 4.0 kWp Energy Photovoltaics modules EPV-40 National Electric Code Standard building codes Electricians, laborers Kiss + Cathcart, Architects Energy Photovoltaics, Inc. Kiss + Cathcart, Architects Fall 1999 2 2 Navajo Nation Outdoor Solar Classroom

02527274m 02527276m 02527275m

The design attempts to establish a connection with Navajo building traditions.

Description Special Design Considerations PV Mounting and Attachment The Seba Dalkai Boarding School, a The installation is designed to minimize Details Bureau of Indian Affairs school on the the cost of the support structure while The PV modules are attached with alu- Navajo Reservation in Arizona, is con- incorporating sustainable construction minum extrusions fixed with silicone to structing a new K-8 facility to be com- materials. Within an enforced simplicity, the back of the glass (four per module). pleted in 2001. Funded by DOE FEMP, this the design attempts to establish a con- Each aluminum channel is 12 ft long. The facility will incorporate a BIPV system nection with Navajo building traditions. channels are supported on a grid of rough capable of producing approximately PV System Configuration timber beams, which in turn are sup- 4.0 kW of electricity. ported by timber columns on concrete The design includes two 25-ft x 25-ft, foundations. The school is currently housed in a open-sided, timber-framed structures. traditional hogan and in a stone facility Each one supports 2.88 kW of semitrans- built in the 1930s. These will remain and parent PV modules, and each one be juxtaposed with a new school facility. includes two Trace 2.5-kW inverters plus The photovoltaic component of this batteries for three days’ worth of energy project will mediate between the old and storage. Each structure will function as an the new, and it will add a structure that open-air classroom. clearly expresses solar technology and BIPV principles. Funded by DOE FEMP, this structure will serve as an outdoor classroom and as part of the school’s HVAC circulation system. It will also be a hands-on laboratory for educating people about BIPV systems and training them in system installation.

design briefs: Navajo Nation Outdoor Solar Classroom 41 design briefs Applicable Electrical Codes: Applicable Building Codes: Tradesmen Required: Solar Consultant: Electrical Engineer: Project Developers: Date Completed: Owner: Location: Interconnection: Interconnection: Inverter Manufacturer: Inverter Number and Size: PV Module Manufacturer: PV Efficiency: PV Cell Type: PV Weight: Gross PV Surface Area: Projected System Electrical Output: System Size: PV Product: General Services Administration, General Williams Services Building 2design briefs: 42 conventional one. (bottom, lower right photo) rather than a (at right in photo above) has a new BIPV roof The Williams nine-story Building in Boston U.S. General Services Administration 408 Atlantic Avenue, Boston, Massachusetts Utility-Grid-Connected Trace Engineering 1 30 kVa Americas, ASE Inc. 12% Amorphous silicon 4 lb/ft Approx. 3,800 ft 50,000 kWh/yr 37 kW DC, 28 kW AC PowerLight, using Americas, ASE Inc., solar panels Specifications National Electric Code, Boston Electric Interconnection Guidelines, and IEEE Standard building codes Electricians and roofers PowerLight Co. PowerLight Co. Enron Energy Services and U.S. General Services Administration September 30, 1999 2 2 General Services Administration, General Williams Services Building

PIX08465

PIX08474 Description Special Design Considerations PV Mounting and Attachment In this project, a regularly scheduled roof The building is located on a wharf, so the Details replacement was upgraded to the installa- design must take into account not only A metal raceway, ballast, and anchoring tion of a building-integrated photovoltaic the water but also 140-mile-per-hour wind system is used. It was also necessary to roof. The BIPV roof is installed on the conditions at the site. add rigid insulation for thermal protection. Williams Building in downtown Boston. After a site review, including a review of The U.S. Coast Guard is the leading tenant The PowerLight RT system is fastened to the wind conditions, the contractor of this 160,000-ft2 building, which sits on the roof along its perimeter using epoxy- decided to use a PowerLight RT photo- Rowe’s Wharf at 408 Atlantic Avenue, near embedded anchors set into the concrete voltaic system. The RT system was chosen the city’s financial district. deck. These use pitch pans and a raceway for its cost-effectiveness when extreme for moisture protection. The system In addition to the new PV system for the roof penetrations are required (for exam- allows water to flow under the roof, the building is also switching from ple, with penthouses, skylights, and HVAC PowerGuard to existing roof drains. It district steam to on-site gas boilers. Two frames). should not be necessary to add new 75-kW Teco-gen co-generation units are drains. also being added, as well as a high- PV System Configuration efficiency chiller, more efficient lighting, This system produces 37 kWp DC and A harness from the panels goes through and upgraded, more efficient motors. 28 kW AC. Its 372 PV panels are con- two conduits into attic space located nected in sets of 12. Each panel has a above the eighth floor. Part of the attic maximum output of 100 watts. needed additional metal decking.

Wiring for the rooftop installation Paul King, DOE Boston Regional Office FEMP liaison, surveys the installation work. PIX08473 PIX08470 PIX08472 PIX08471

View of the new BIPV roof on the Williams Building, during and after construction

Pavers are in foreground, PV array is in background on the rooftop.

design briefs: General Services Administration, Williams Building 43 02527263m

The plan for the roof of the Williams Building included a rooftop BIPV system consisting of 372 solar panels. Jeff Ansley, PowerLight Corporation/PIX08461 Ansley, Jeff Jeff Ansley, PowerLight Corporation/PIX08466 Ansley, Jeff

Co-funded by the DOE FEMP Renewable Energy Shading from other buildings is not a problem at this Program, this BIPV application illustrates how the site, which is in urban Boston. technology can be introduced into complex roof spaces.

44 design briefs: General Services Administration, Williams Building design briefs Academy of Further Education design briefs: Projected System Electrical Output: Size: PV Product: Tradesmen Required: Electrical Engineers: Structural Engineers: Architect & Designer: Date Completed: Owner: Location: The Academy of Further Education under construction in Herne, Germany Interconnection: Inverter Manufacturer and Model: Inverter Number and Size: PV Module Manufacturer: PV Efficiency: PV Cell Type: PV Weight: Gross PV Surface Area: Academy of Further Education EMC, Ministry EMC, of Interiors of North Rhine-Westphalia, City of Herne Herne, North Rhine-Westphalia, Germany Utility-Grid-Connected SMA, Kassel 600, 1.5 kW Pilkington Solar International, Cologne 12.8% to 16% Polycrystalline and monocrystalline silicon 130 kg per each 3.2 m 10,000 m 750,000 kWh/yr 1 MWp roof BIPV Glaziers, electricians HL-Technik Schleich, Bergermann and Partner Jourda et Perraudin Architects, ArchitectsHHS May 1999 2 2 module 45

PIX08454 Description As part of the International Construction Exhibition, Emscher Park, the site of a for- PIX08455 mer coal mine in Herne, Germany, is being used for a new purpose. A comprehensive urban development plan is providing the district of Sodingen with a new center- piece: the Academy of Further Education, Ministry of Interior, North Rhine- Westphalia. The large glass hall incorporates not only the Academy but also a hotel, library, and administrative municipal offices. The glass hall is multifunctional. It protects the interior from harsh weather and uses solar energy both actively and passively by producing heat as well as electric power. Special Design Considerations Approximately 3,180 multifunctional roof and facade elements are the core of the An inside view of the Academy building as construction progressed solar power plant. With a total area of 10,000 square meters, most of the roof and the southwest facade is covered by photovoltaics, making this system the PIX08456 largest building-integrated PV power plant in the world. It produces approximately 750,000 kWh of electric power per year. This is enough to supply more than 200 private residences. About 200,000 kWh is used directly by the Academy building, and the remaining 550,000 kWh is fed into the public power grid in Herne. PV System Configuration The Optisol photovoltaic elements were produced by Pilkington Solar at a site in Germany. The PV system consists of solar cells embedded between glass panes. Daylighting needs were taken into account in designing the roof- and facade- integrated system. The PV modules have areas of 2.5 to 3.2 square meters and an output of 192 to 416 peak watts each. This This photo shows how the PV panels are angled to capture the sunlight makes them larger and more powerful shining on the roof. than most conventional solar modules. Mounting and Attachment Direct-current electricity is converted to 230 V alternating current by means of Details a modular inverter. This is made up of The building-integrated photovoltaic roughly 600 decentralized string inverters panels are set into aluminum mullions and allows optimal use of the incident like skylights. The rooftop panels are solar radiation. positioned at an angle to capture as much of the incident sunlight as possible.

46 design briefs: Academy of Further Education PIX08457

Rooftop view shows placement of insulation and PV panels.

design briefs: Academy of Further Education 47 design briefs Size: PV Product: Applicable Electrical Codes: Applicable Building Codes: Tradesmen Required: Electrical Engineers: Structural Engineers: Architect & Designer: Scheduled Completion Date: Location: Interconnection: Inverter Manufacturer and Model: I PV Module Manufacturer: PV Efficiency (%): PV Cell Type: PV Weight: Gross PV Surface Area: Projected System Electrical Output: Discovery Science Discovery Center 8design briefs: 48 nverter nverter Number and Size: November 1999 Santa Ana, California Utility Grid-Connected Omnion 2400, Model 5015 4 Solarex BP 5.1 % Thin-film technology 3 lb/ ft 4,334 ft 30,000 kWh/yr 20 kWp Thin-film photovoltaic system National Electric Code Building Administrators Code Administrators International (BOCA) Electricians Solar Design Associates, Inc. Advanced Structures, Inc. Arquitectonica for the cube, Solar Design Associates for the PV system 2 2 Discovery Science Discovery Center

California in Santa Ana, Science Center Cube of the Discovery Architect’s rendering Solar Design Associates, Inc./02527271 Description architectural glazing element, replacing Science Center, displacing conventional what would have been a glass canopy. utility power. When the solar system This solar electric system, located in They produce up to 20 kW of DC electricity produces more electricity than the Santa Ana, California, boasts one of the at mid-day and 30,000 kWh of electrical Science Center needs, the excess elec- world's largest building-integrated thin- energy per year, which is enough to run tricity is "exported" to the utility, thereby film applications to date. The PV-covered four typical homes. effectively spinning the electric meter surface of the cube is tilted at 50° for backwards. maximum visual impact and optimal solar The solar energy system is connected harvest. BP Solarex's Millennia modules to the Discovery Science Center's main cover the entire 4,334-ft2 top of the cube utility line. When the solar system pro- The thin-film modules are treated as an duces energy, it feeds the energy to the Solar Design Associates, Inc./02527277m Solar Design

The view from inside the cube

design briefs: Discovery Science Center 49 design briefs Size: PV Product: Applicable Electrical Codes: Applicable Building Codes: Tradesmen Required: Electrical Engineers: Structural Engineers: Architect & Designer: Date Completed: Location: Interconnection: Inverter Manufacturer and Model: Inverter Number and Size: PV Module Manufacturer: PV Efficiency: PV Cell Type: PV Weight: Gross PV Surface Area: Projected System Electrical Output: Solar Sunflowers 50 N/A Napa, California Utility-Grid-Connected Omnion Series 2400, Model 6018 6 Solarex BP 11.1% Polycrystalline 3.4 lb/ ft 3,456 ft N/A 36,000 Wp Solarex BP National Electric Code Building Officials Code Administrators International (BOCA) Electricians Solar Design Associates, Inc. Solar Design Associates, Inc. Solar Design Associates, Inc. 2 2

electricity. track the sun to produce These Solar Sunflowers PIX08468 design briefs: Solar Sunflowers Description Just like a sunflower, the Solar Electric Sunflowers look and act like nature's own Nestled atop a hillside in Northern variety. Making use of a two-axis tracking California, 36 Solar Electric Sunflowers system, the sunflowers wake up to follow represent an elegant combination of art the sun's path throughout the day, and technology. The clients requested an enabling the system to produce enough unconventional and artistic installation. energy for eight to ten homes. They got just that. PIX08467

Solar electric sunflowers resemble nature’s own.

design briefs: Solar Sunflowers 51 design briefs PV Product: Applicable Electrical Codes: Applicable Building Codes: Tradesmen Required: Electrical Engineers: Structural Engineers: Architect & Designer: Date Completed: Location: Interconnection: Interconnection: Inverter Manufacturer and Model Inverter Number and Size: PV Module Manufacturer: PV Efficiency: PV Cell Type: PV Weight: Gross PV Surface Area: Projected System Electrical Output: Size: Ijsselstein Row Houses 2design briefs: 52 building-integrated photovoltaics: front (above) and back views. Fourteen planned new row-house units in the Netherlands demonstrate the aesthetic use of N/A : Scheduled for completion in late 2000 Ijsselstein Zenderpark, Ijsselstein, The Netherlands Utility-Grid-Connected N/A EPV 6% Amorphous silicon, both opaque and 15% translucent 3.75 lb/ft 30 m 1150 kWh/year per housing unit 1.6 kWp per housing unit Standard-size glass laminate BIPV panels Dutch Electrical Code Dutch Building Code Building tradesmen N/A N/A Architects, co-designer Han Van Zwieten, Van Straalen Architecten, co-designer; Gregory Kiss, Kiss + Cathcart 2 per housing unit 2 Ijsselstein Row Houses

02527270m 02527269m 02527268m

rooster M.K. M.K.

Sample floorplans for row-house units

Description positive responses among many Dutch chimney that actually uses the heated architects, who perceive them as looking air produced in the sunrooms to draw air This Dutch-American design collaboration much more like an architectural material currents through the entire row house, is intended to develop a new standard in than polycrystalline panels do. cooling it in warm weather. Cold weather Europe for moderately priced housing conditions are addressed simply by with integrated solar electric systems. The Special Design Considerations providing a suitable layer of insulation first phase consists of 14 row-house units, In marked contrast to the United States, between the cladding and the interior each with its own grid-connected BIPV The Netherlands favors residential design finish. array. As part of a highly ordered "new that is largely modern and rational in town" development adjacent to the city character. The ubiquitous pitched roofs PV System Configuration center of Ijsselstein, these units conform of North American houses (which provide A 1.6-kW, grid-connected BIPV system is to strict space and budget guidelines convenient mounting surfaces for PV part of each row house. Each system will as well as to advanced standards of PV arrays) were considered aesthetically be individually metered, and there is no integration. undesirable at Ijsselstein. However, at battery storage. The overall design is a composition of higher latitudes with low sun angles, ver- brick volumes and two-level, wood- tically mounted BIPV panels can generate PV Module Mounting and framed sunrooms. The latter are partially power at output levels competitive with Attachment Details clad in opaque and translucent PV units, those of optimally angled panels. The Standard PV modules are set into a wood and they are raised and staggered to design takes advantage of this by using framing system, which can be either site- maximize solar exposure. The sunroom standard-sized units as glazing and built or prefabricated. The opaque units volumes are wood-paneled on the sides exterior enclosure combined in a simple are set as typical single glazing, using facing north. wooden frame wall. minimum-profile glazing stops and caulk. The translucent panels are incorporated The Netherlands is home to some of the Extensive computer modeling studies into double-glazed window units. The most advanced PV systems in the world. were done to ensure that the complex horizontal members of the wood frame However, before this project began, little massing of the row houses works to pro- have an absolute minimum exposed work had been done on integrating solar vide maximum solar exposure for each depth to prevent shadowing. The vertical arrays into the prevailing Dutch architec- unit’s array and minimum shadowing of members, which are not as likely to inter- tural idiom of abstract cubic forms. The BIPV surfaces by adjacent units. fere with solar exposure, have a raised Ijsselstein row houses demonstrate how Given that BIPV glass is a major cladding profile. photovoltaics can be a fully participating component for the sunroom elements, element in the design, rather than just excessive interior heat loss or gain was an applied system. Amorphous silicon a significant design consideration. The modules in particular are generating very adjacent stair serves as a convection design briefs: Ijsselstein Row Houses 53 design briefs Applicable Building Codes: Tradesman Required: Electrical Engineers: Structural Engineers: System Integration: Architect & Designer: Date Completed: Owner: Location: Interconnection: Suggested Inverter Manufacturers: Inverter Number & Size: PV Module Manufacturer: PV Efficiency: PV Cell Type: PV Module Weight: Gross PV Surface Area: Projected System Electrical Output: Size: PV Product: Applicable Electric Codes: Denver Federal Courthouse 4design briefs: 54 The U.S. Court House expansion in Denver will be a showcase for sustainable building design. U.S. General Services Administration Denver, Colorado Utility-Grid-Connected Trace Technologies, Trace Engineering, Omnion One 20-kW and one 3.4-kW inverter Pilkington Solar 10% or greater Single- or polycrystalline silicon 2,749 kg 4,661 (skylight) kg (roof); 172 m 20,150 4,700 kWh kWh per per year year (roof); (skylight) 3.4 kWp 15 (skylight) kWp (roof); Custom-sizedglass laminate BIPV National Electric Code (1999) Uniform Building Code (1997) Building tradesmen/glaziers The Group,RMH Inc. Inc. Martin/Martin, Altair Energy (PV Consultant) (Designers); Architectural Energy Corporation (Energy Consultants) Anderson Mason Dale (Architects); Hellmuth, Obata, & Kassabaum, St. Louis Scheduled for completion in 2002 2 (roof); 59 m (roof); 2 (skylight) Denver Federal Courthouse

02527279m Insulated Photovoltaic Standard Glass

02527278m Skylight Glazing

02527294m

Photovoltaics will be integrated into the top roof louver of the tower and into a skylight above the lobby rotunda.

Description and a special proceedings courtroom. courthouse tower caps the structure Anderson Mason Dale P.C. is the architect with an open framework and a floating The United States Courthouse Expansion of record, and HOK served as the design horizontal roof of photovoltaic panels. in Denver, Colorado, consists of 17 new architect. courtrooms and associated support With technical assistance provided by spaces for an additional 383,000 ft2 Recalling a traditional town square FEMP, the project’s sustainable design (35,600 m2). The U.S. General Services courthouse, the two-story pavilion is an consultant, Architectural Energy Corpora- Administration (GSA) approached the arrangement of two geometric forms tion of Boulder, Colorado, and the design expansion of this Federal Courthouse in under a large horizontal roof. It is the team developed the building’s overall downtown Denver as a showcase building frontispiece of the entire composition. sustainable design strategies. The build- for sustainable design. One of the GSA’s An open peristyle colonnade supports ing achieves a high level of energy effi- project goals was to "use the latest avail- the roof and transparently encloses the ciency through a combination of able proven technologies for environmen- entrance lobby and the drum-shaped strategies that seek first to reduce build- tally sensitive design, construction, and secured lobby. As a series of vertically ing energy loads as low as possible and operation. It should set a standard and be oriented rectangular planes, the then to satisfy the remaining reduced a model of sustainable design." Another goal was to create a building that would remain usable for its 100-year lifespan. This chart summarizes the BIPV system design: The design projects an image of respect Component Orientation Effective Size Annual and reflects the city’s rich architectural Area (m2) (kW) kWh heritage. The 11-story structure houses Roof area Horizontal 173.4 13.9 23,300 six floors of district courts, two floors of magistrate courts, offices for the United Lobby skylight Horizontal 63.6 4.4 7,400 States Marshal, a jury assembly area, design briefs: Denver Federal Courthouse 55 loads through state-of-the-art, high- expresses both energy efficiency and Special Design Considerations efficiency mechanical and electrical sys- adaptation to climate. The glazing- The basic laminated BIPV glazing panels tems and renewable energy sources. The integrated PV array at the top horizontal are a compilation of square polycrystaline unique attributes of the Denver climate, roof louver of the tower is composed of cells measuring 125 mm x125 mm. The sunny skies and low humidity, are used crystalline cells covering approximately manufacturing process varies the density throughout the design to minimize energy 87% of the visible glazing area. This is and coverage of these cells within the consumption. The resulting building is intended to be a highly visible element of BIPV panel to accommodate the design a visible expression of sustainability the building’s architecture, recognizable intent. This ability to custom-design indi- through features that work together in from many places around the city. vidual BIPV panels allowed the design an integrated energy-efficient system. The cylindrical volume of the secure lobby team to specify skylight panels to be more The improved building envelope allows rotunda culminates in an insulated BIPV light transmissive, thereby providing substantial reductions in energy use for glass skylight using crystalline cells cover- ample illumination of the lobby rotunda, lighting, ventilation, and cooling. These ing approximately 60% of the visible glaz- and to design the roof louver panels with reductions, along with the energy gener- ing area; it provides necessary shading greater opacity, thereby providing ated from the BIPV system, will make the while generating power for the building increased power capabilities. annual operating energy costs of the new and making a statement about alternative The laminated BIPV glazing panel of the courthouse 43% lower than those of a energy sources. Perimeter skylights skylights allows the phototvoltaic system building designed according to Depart- around the outside of the rotunda are to be responsive to indoor safety and ment of Energy standards for energy laminated glass. Setting the tone for security requirements. Condensation con- efficiency (10 CFR Part 436, which is other special places within the building, cerns also required that the skylight’s based on ASHRAE 90.1-1989). a perforated metal scrim ceiling diffuses BIPV panels be integrated into an insu- this light. Energy savings were calculated by con- lated glazing element. structing a simulation model of the build- The BIPV panels provide electricity during In addition, the inside glass pane is lami- ing that meets the minimum requirements daylight hours, reducing the building’s nated with a milk-white, PVB (polyvinyl of the Federal Energy Standard (10 CFR peak electricity requirements. Direct cur- butyral) inner layer to diffuse direct sun- Part 435). This minimally compliant build- rent from the BIPV system is fed into the light and obscure the less visually appeal- ing (the base building) was the baseline building’s electrical system via a DC to AC ing side of the crystalline cells from view. from which energy savings were calcu- power-conditioning unit. Since the system lated. A comparison of the simulated is utility-interconnected, battery storage PV System Configuration annual energy costs for the base building is not necessary. Estimated total energy A one-line electrical schematic is given and the proposed design is shown below. production from the two systems is for the two photovoltaic systems. The approximately 25,000 kWh per year, or Local materials, such as precast concrete photovoltaic modules are wired in series about 2% of the building’s total annual and native stone, have been incorporated and parallel to meet the voltage and cur- electrical consumption. into the exterior cladding system. The rent input requirements of the power building will have a steel frame with recy- The new U.S. Federal Courthouse expan- conditioning unit (PCU). To simplify the cled material content. Most of the flooring sion lends an optimistic, forward-looking wiring between the PV array and the PCU, materials in the building are made from image to the City of Denver while making combiners are installed near the array. recycled or native sources, including a strong case for sustainable design. The array combiners include reverse native stone, cork, or recycled plastics. Inside the courthouse, the design will current protection, surge protection, Low-impact landscaping is used to mini- project a bright, airy appearance. "Green" and series string fusing, and they provide mize water use, reduce the "urban heat design features also improve the work a convenient place for testing and island" effect, and provide an attractive environment, which can lead to increases troubleshooting the PV array. outdoor space. Low-flow lavatory faucets in employee productivity and satisfaction. DC and AC disconnects enable proper and water closets will be used throughout By investing in improved materials and disconnection and protection for the PCU. to minimize water use. All interior finish systems, and using an integrated, envi- Depending on whether the output of the materials were carefully selected on the ronmentally conscious design approach, PCU is compatible with utility voltage and basis of their impacts on the environment the GSA will reduce environmental grounding requirements, an external (to and occupants. impacts as well as long-term operating the PCU) isolation transformer may be The building is crowned by a series of costs. Because the courthouse expansion needed. A utility-required relay mecha- glazing-integrated PV modules incorpo- has been designated a "demonstration nism provides over- and under-frequency rated into the top horizontal roof louver of project" by GSA, it will be used to influ- protection and over- and under-voltage the tower and the skylight element above ence future courthouse design projects. protection. The utility disconnect is a the cylindrical volume of the secure lobby redundant measure required by the utility rotunda. This bold architectural statement to ensure that the PV system will not

56 design briefs: Denver Federal Courthouse backfeed utility lines that are not meant (2) Wind speed (m/s) will measured with available on this display, along with to be energized. The PCU has an anti- an NRG systems cup anemometer educational screens. islanding feature that is the first line of mounted near the array. PV Module Mounting and defense against undesired backfeed Attachment Details onto the utility grid. The point of intercon- (3) Ambient temperature (°C) will be nection can be made in any electrical measured with a thermistor inside The glazing-integrated PV modules will distribution panelboard with the proper a radiation shield mounted near the be shipped to the site individually with voltage and current ratings. array. terminals for making electrical connections. Because the skylight installer will Because the BIPV arrays are located in (4) PV system AC power/energy output mount the modules into the mullions and different places on the building, each (kW/kWh) will be measured with a make the electrical connections, the elec- array will be equipped with its own data standard accumulating energy meter trical connections must be very simple. acquisition system. The data acquisition with a special pulse output device. Electrical terminals are located on the systems will measure and record four This device will be located near the panel edges so they are concealed by parameters that can be used to scrutinize PCU. the mullion system. Traditional modules the performance of the BIPV systems. have a junction box mounted on the back. These parameters are the four required The data from the two data acquisition Special plug-and-socket connectors will by the Utility Photovoltaic Group (UPVG) systems will go to a central computer via enable easy one-wire connections to be for its monitoring and rating program. standard telephone wire. The computer made between adjacent modules. The This may also make the PV systems will probably be in a busy area, such as mullions will be constructed so that indi- eligible for cost-sharing with UPVG. The the special proceedings lobby, to help vidual modules may be removed for following measurements and sensors educate the general public about BIPV repairs. will be employed: systems. The computer will have custom- designed software for displaying the data (1) Plane-of-array global solar irradiance in a "cockpit" format (i.e., with graphic (W/m2) will be measured with a Licor elements such as dials and strip charts). pyranometer mounted on the array. Both real-time and archived data will be

Insulated Photovoltaic Tower Glass BIPV Roof Louver

Standard Skylight Glazing

02527293m 02527292m

These drawings show the position of BIPV modules on the skylight and the tower roof louver.

design briefs: Denver Federal Courthouse 57 BIPV Basics Photovoltaic Technologies One of these PV materials, silicon, is highly abundant; it constitutes more PV Cells A French physicist, Alexandre Edmond than 25% of the Earth's crust. Silicon is PV cells are the basic building blocks Becquerel, was the first to record his used in more than 90% of all PV appli- of PV modules. They are made of semi- observation of the photovoltaic effect cations, including building-integrated conducting materials, typically silicon, (photo denotes light and voltaic denotes photovoltaics or BIPV. Silicon solar doped with special additives. Approx- the generation of electricity) in the 19th technologies can be grouped in these imately 1/2 volt is generated by each century. Since then, many scientists three basic areas: single-crystal silicon, silicon PV cell. The amount of current have worked to develop energy tech- polycrystalline silicon, and thin-film produced is directly proportional to nologies based on this effect. It is a amorphous silicon. The primary dis- the cell’s size, conversion efficiency, process in which electricity is generated tinctions among the three technologies and the intensity of light. As shown in in the boundary layers of certain semi- are their sunlight-to-electricity conver- the figure below, groups of 36 series- conductor materials when they are sion efficiency rates, the methods by connected PV cells are packaged illuminated. Today’s photovoltaic semi- which they are manufactured, and their together into standard modules that conductor materials include silicon, associated manufacturing costs. provide a nominal 12 volt (0r 18 volts gallium arsenide, copper indium dise- @ peak power). PV modules were lenide, cadmium sulfide, and cadmium The efficiency of each BIPV product originally configured in this manner telluride. is specified by the manufacturer. to charge 12-volt batteries. Desired Efficiencies range from as low as 5% Photovoltaic materials are classified as power, voltage, and current can be to as high as 15%–16%. A technology's either crystalline, polycrystalline, or obtained by connecting individual PV conversion efficiency rate determines thin-film in form. These classifications modules in series and parallel combi- the amount of electricity that a com- represent the three major PV technolo- nations in much the same way as mercial PV product can produce. For gies. These are the building blocks for batteries. When modules are fixed example, although thin-film amor- today's commercial PV products, together in a single mount they are phous silicon PV modules require less which include consumer electronics called a panel and when two or more semiconductor material and can be less (such as a solar-powered calculator or panels are used together, they are expensive to manufacture than crys- watch), remote electric power systems, called an array. (Single panels are also talline silicon modules, they also have utility-connected power systems, and called arrays.) lower conversion efficiency rates. Until building-integrated systems. these conversion efficiencies increase, Cell

The Photovoltaic Effect Sunlight is composed of photons—discrete units of light energy. When photons strike a PV cell, some are absorbed by the semiconductor material and the energy is transferred to electrons. With their new-found energy, the electrons can escape Module from their associated atoms and flow as current in an electrical circuit. PV arrays require no care other than occa- sional cleaning of the surfaces if they become soiled or are used in dusty locations. However, they must be kept clear of snow, weeds, and Light energy other sources of shading to operate properly. PV cells are connected in series, so shading Panel even one cell in a module will appreciably decrease the output of the entire module. Array

n-Type semiconductor Electrical p-Type energy semiconductor

Photovoltaic device 02527264m 02527265m

58 BIPV Basics PV modules were connected to, or mounted on, buildings that were usually in remote areas without access to an electric power grid. In the 1980s, PV module add-ons to roofs began being demonstrated. These PV systems were usually installed on utility-grid- connected buildings in areas with cen- tralized power stations. In the 1990s, BIPV construction products specially designed to be integrated into a building envelope became commercially available.

Internationally, the past decade has ushered in a myriad of BIPV demonstration buildings and other structures. In both new projects and renovations, 02527266m BIPV is proving to be an effective building energy technology in residential, commercial, industrial, and institu- Schematic of a typical stand-alone PV system tional buildings and structures.

BIPV systems are considered to be Utility service multifunctional building materials, connection and they are therefore usually designed to serve more than one function. For kWh example, a BIPV skylight is an integral meter PV array component of the building envelope, Source a solar energy system that generates combiner electricity for the building, and day- with DC UI Electrical lighting element. Lightning string DC/AC AC distribution panel protection disconnects DC inverter AC disconnect The standard element of a BIPV system is the PV module. Individual solar cells are interconnected, encapsulated, lami- AC to all loads nated on glass, and framed to form a 02527267m module. Modules are strung together in an electrical series with cables and Block diagram of a utility-interactive PV system wires to form a PV array. Direct or diffuse light (usually sunlight) shining on more amorphous silicon modules will modules are a reddish-brown to black; the solar cells induces the photovoltaic be required to generate the same the surface may appear uniform or effect, generating unregulated DC elec- amount of electric power produced by nonuniform, depending on how the tric power. This DC power can be used, other silicon-based PV modules. modules are made. Consequently, stored in a battery system, or fed into Continuing research and development typical system colors are blues, browns, an inverter that transforms and syn- in thin-film silicon should increase its and black. However, some PV manu- chronizes the power into AC electricity. conversion efficiencies. facturers can fill special orders for col- The electricity can be used in the build- ors such as gold, green, and magenta. ing or exported to a utility company An important architectural considera- These color variations will result in through a grid interconnection. tion is aethetics, and PV modules do some loss in performance efficiencies. differ in appearance. Single-crystalline BIPV systems are made up of BIPV PV modules are dense blue (almost BIPV Systems construction materials and balance-of- black), with a flat, uniform appearance. system (BOS) hardware. The BOS hard- PV applications for buildings began Polycrystalline modules are multicol- ware is composed of cabling, wiring, appearing in the United States and else- ored, having a variety of sparkling blue and structural elements that hold where in the 1970s. Aluminum-framed tones. Thin-film amorphous silicon the modules in place, as well as

BIPV Basics 59 grid-metered connections, fault pro- system orientation and tilt, electrical basis. In comparison to a system's per- tectors, a power conditioning unit characteristics, and system sizing. formance at latitude angle, annual (inverter), and an electricity storage performance losses for vertical facade system (usually batteries), as needed. Solar access — Solar access, the inci- systems can be as high as 30% or more. dence of solar radiation (insolation) In contrast, annual performance losses Demonstrations of BIPV systems have that reaches a PV surface at any given for horizontal installations can be as greatly increased people's awareness time, determines the potential electrical high as 10%, in comparison to those of of the potential of BIPV products. This output of a BIPV system. Solar systems installed at latitude angle. is especially true for members of the radiation data for sites in the United building profession and construction States can be obtained from the Electrical Characteristics — The perti- trades. At the same time, the PV indus- Department of Energy's National nent electrical characteristics of a PV try has gained experience in designing, Renewable Energy Laboratory (NREL). module or array are summarized in the manufacturing, and installing BIPV The data are available in publications relationship between the current and systems. The current challenge for the such as the Solar Radiation Data Manual voltage. The amount and intensity of industry is to penetrate the commercial for Flat-Plate and Concentrating Collectors solar insolation controls the current (I); construction market. This is being and the Solar Radiation Data Manual for the temperature of the solar cells affects achieved through new linkages Buildings (call (303) 275-4363 to request the voltage (V) of the PV module or between PV manufacturers and the copies) or online from the Renewable array. Module I-V curves that sum- building materials manufacturing Resource Data Center (http://rredc. marise the relationship between the industry. nrel.gov). Statistical estimations of current and voltage are furnished by average daily insolation levels for spe- manufacturers. I-V curves provide The economics and aesthetics of BIPV cific locations are commonly used in information designers need to config- systems are optimized when PV is the BIPV design process and measured ure systems that can operate as close integrated into the building during pre- as kilowatt-hours per square meter per to the optimal peak power point as liminary design stages. In order to be day (kWh/m2/day). possible. The peak power point is mea- effective, BIPV products should match sured, under standard testing condi- the dimensions, structural properties, System Orientation and Tilt — To max- tions (STC), as the PV module produces qualities, and life expectancy of the imize solar access and power output, its maximum amount of power when materials they displace. Like standard the physical orientation of the BIPV exposed to artificial solar radiation of construction glass, cladding, and roof- system and the tilt angle of the array 1000 W/m2. ing materials, they can then easily be should be considered relative to the integrated into the building envelope. geographical location of the building System Sizing — Choosing a BIPV type site. As a general rule of thumb, BIPV and sizing a system have three main Design Issues installations north of the equator per- components: energy loads, architectural Beyond comfort and aesthetics, BIPV form optimally when oriented south or aesthetic considerations, and eco- design considerations encompass both and tilted at an angle 15 degrees higher nomic factors. To determine the desired environmental and structural factors. than the site latitude. Conversely, BIPV power rating of a BIPV system for a Environmental factors include a struc- installations south of the equator per- building, the electrical requirements of ture's solar access as well as average form best when oriented north and the building should first be evaluated. seasonal outdoor temperatures at the tilted at an angle 15 degrees lower than The optimum power rating of the sys- site, local weather conditions, shading the site latitude. The orientation and tem can be calculated and sized, based and shadowing from nearby structures tilt may vary from this formula when on the portion of the building's electric- and trees, and the site's latitude, which a BIPV system's particular seasonal ity that will be supplied by the BIPV influences the optimum BIPV system performance must be optimized. For system. For example, an autonomous or orientation and tilt. Structural factors example, a system might be designed off-grid building may require a large include a building's energy require- to produce maximum power output system with battery storage capabilities ments, which influences the size of the only in the summer months in order to provide 100% of the building's elec- system, and the BIPV system's opera- to reduce peak electricity costs for air- tricity requirements; a building owner tion and maintenance requirements. conditioning loads; thus, the system desiring to reduce demand charges will These factors must all be taken into should be installed at an optimum require a small system that produces account during the design stages, when orientation and tilt for summer power electricity only during peak utility the goal is to achieve the highest possi- output. charge hours. ble value for the BIPV system. Some of Demonstrations have shown that a sys- Architecturally, the size of the BIPV the major design considerations unique tem installed at a tilt angle equivalent system is physically limited to the to solar energy systems are solar access, to the site latitude produces the greatest dimensions of the building's available amount of electricity on an annual surface area. The balance between the

60 BIPV Basics amount of power required and the the inverter from DC to AC power and lifetime of the PV module. If the amount of surface area available can then fed into the building or an electric inverter has a lifetime of only 5 years determine the type of PV technology utility system. If the inverter fails, the and the BIPV facade lasts 25 years, that will be used. Each technology has entire system malfunctions. replacing the modular inverter has an an associated range of output in watts associated periodic cost, and access per square foot or per square meter and Today, most inverters are highly reli- needs to be anticipated and designed cost per watt. For example, systems able. However, the practice of relying into the project. made of amorphous silicon require a on only one inverter for a BIPV system larger surface area but cost less than in a commercial building is problem- The string inverter is the second equivalent systems composed of single- atic. When BIPV systems are made generation of inverters for buildings. crystal solar cells. Therefore, in projects up of a large series of interconnected In Europe, one string inverter with the that have a limited budget but include a strings, there is a technical difficulty in nominal power of 750 watts can con- large south-facing facade surface area, determining where a system has failed. nect as many as 10 PV modules in a amorphous silicon can be the most suit- This is akin to the problem people had series and be connected anywhere in able BIPV technology.To achieve the with old-fashioned Christmas tree the building's electricity distribution appearance of a uniform surface area, lights. When one light malfunctioned, system. The flexibility, reliability, and less expensive "mock" or imitation PV the entire string went down, and each increased efficiency offered by string panels can also be provided by the bulb had be tested to determine the inverters may further reduce the cost manufacturer. source of the problem. of BIPV systems.

Once the building energy load require- A BIPV system designed so that multi- New AC modules are being equipped ment is determined, the watt-hour ple inverters work together ensures with individual AC mini-inverters method can be used to design the elec- greater system reliability. If one inverter mounted on the backs of the PV panels. trical system. An evaluation of seasonal malfunctions or requires maintenance, They are at the early commercial stages climatic conditions and variations (tem- it can be disconnected from the array of development in the United States perature and solar insolation) and the and the BIPV system can still operate. and Switzerland. One benefit of these available surface area will determine A cascading hierarchy "master-slave" is that they eliminate the need in the the number of modules that will satisfy configuration includes one master building for the high-voltage DC the voltage and current requirement inverter and multiple slave inverters wiring associated with other BIPV of the load. After that, corresponding that operate together for maximum systems. inverter requirements and BOS require- efficiency In regard to electrical safety issues, ments can be specified. Currently, PV Modular, "micro," or "mini" inverters it is important to note that lightning, specialists, system integrators, and allow each module to be tested (each ground faults, and power line surges consultants provide electrical sizing has its own address) through the use can cause high voltages in otherwise information, assessments, and recom- of a power line carrier signal injected low-voltage BIPV systems. National mendations. However, BIPV manufac- into the building's electrical distribu- and international electric code regula- turers are increasingly providing full tion system. This way, each unit's tions and building codes are being turn-key services for large systems performance can easily be evaluated. amended to include PV technologies for commercial buildings, and prepack- Modular inverters also enable PV to and address fire and safety issues con- aged, standardized, residential systems be integrated into complex, geometric cerning BIPV design, installation, and are being sold by distributors. For more building designs. maintenance. information on software tools for optimizing PV systems, see Appendix B. Modular inverters are desirable for Codes and Standards commercial buildings because they The national model codes historically Electrical and Safety Issues operate independently. Shading one have been composed of three primary Electrical issues primarily involve the module will not interrupt the power organizations: the International performance and reliability of the output of the whole array. In single or Conference of Building Officials inverters. The variety available for multiple inverter systems, a number (ICBO), Building Officials Code BIPV systems include single inverters, of modules are connected in series to Administrators International (BOCA), master-slave inverter configurations, achieve the voltage needed by the and the Southern Building Code modular inverters, and parallel- selected inverter. Shading any one Conference International (SBCCI). independent or string inverters. A module in this series can negate the These organizations have collaborated BIPV system is most vulnerable to a output of the entire string. to create one umbrella organization, single-point failure where the power the International Code Conference generated from the BIPV array must be One design issue related to the modular (ICC). The ICC has begun the process transformed and synchronized through inverter is whether it will last the

BIPV Basics 61 of writing one model code, the Inter- 2000 by the International Residential package known as FEDcheck to assist national Building Codes. These codes Code. The CABO document is not users in understanding and complying began development in 1996, and the being updated at this time, and changes with the code. For more information, entire group will be published by the will need to be made to the IRC. The contact Stephen Walder, DOE, 202- year 2000. Although these codes must change process for both the IECC and 586-9209, or Robert Lucas, Pacific be adopted by each municipality to IRC will occur annually until 2003 and Northwest National Laboratory, have any authority, they will be the at three-year intervals after 2003. 509-375-3789 (online, see http://www. most up-to-date ones that can be energycodes.org/federal/federal.htm). adopted after the year 2000. This is a Commercial Codes & Products — DOE major step toward a unifying model supports commercial energy codes, DOE has also prepared a third edition code, reducing the duplication and especially ASHRAE 90.1, by helping to of its Building Standards and Guide- diversity of the previous three code develop them and by providing tools lines Program catalogue. This catalogue bodies. The change process for all ICC and resources that make the codes is one of many services that promote codes will occur annually until 2003 easier to use. The COMcheck-EZTM the adoption, implementation, and and at three-year intervals after 2003. materials were developed to simplify enforcement of residential and com- and clarify commercial and high-rise mercial building energy codes. One of To date, these codes do not refer specifi- residential building energy code the primary goals of the program is to cally to BIPV systems, leaving compli- requirements. The materials include provide products and services that ance to the discretion of local building easy to use IBM-compatible software; make it easy for builders, architects, inspectors. If BIPV is the structural compliance guides for envelope, light- designers, building code officials, and equivalent of a current building mater- ing, and mechanical requirements; and state energy officials to implement ial, only specific code provisions or prescriptive packages for county-based building energy codes. compliance required for the structural climate zones. Forms and a checklist equivalent will be necessary. However, are included to document compliance. The catalogue features many products the typical crystalline PV cell adds All COMcheck-EZ materials can be that will quickly and efficiently imple- weight to the traditional building downloaded at no cost. If you down- ment the requirements of the Model product relative to a thin filmed glaz- load any material, please register with Energy Code; the American Society ing, and this may require closer evalua- the program so you will be notified of of Heating, Refrigerating, and Air- tion by code officials. Because of their upgrades (online, see http://www. Conditioning Engineers and Illumin- multifunctional nature, BIPV systems energycodes.org/comm/comm.htm). ating Engineering Society of North must also comply with the National America Standard 90.1-1989; and the Electric Code (NEC), which addresses Federal Building Codes — The current Federal Performance Standards for PV power systems but not BIPV Federal code for low-rise residential New Commercial and Multi-Family specifically. energy efficiency (10 CFR Part 435, High-Rise Residential Buildings. sub-part C) can be obtained online (see Local codes vary by state and munici- http://www.access.gpo.gov/nara/cfr/ In addition to the catalogue, the pality, and some covenant-controlled cfr-retrieve.html#page1). DOE has been MECcheck and COMcheck-EZ compli- communities regulate the appearance updating this code. The proposed rule- ance tools and manuals may be down- of buildings for architectural aesthetics making for the Energy Efficiency Code loaded at no cost from the Building and homogeneity. This may affect deci- for new Federal Residential Buildings Standards and Guidelines Web site at sions about the suitability of BIPV sys- was published in the May 2, 1997, edi- http://www.energycodes.org/. For tems. Furthermore, a few communities tion of the Federal Register. A printed more information, or to place an order, in the United States have developed copy of the rulemaking can be obtained call the U.S. Department of Energy zoning ordinances relative to solar in Federal Register Volume 62, Number Building Standards and Guidelines access laws that could affect BIPV sys- 85, pages 24163-24209, or at the online program hotline at 1-800-270-CODE tems and structures that may shade address above. (online, see http://www.energycodes. solar systems. org/news/catalog.htm). The proposed rule is based on the 1995 Residential Energy Codes — The Model version of the Model Energy Code, but State Energy Codes — The status of Energy Code (MEC) has been pub- it contains more stringent envelope each state’s building energy codes is lished by the Council of American requirements and rules related to radon current as of September 1997. The list is Building Officials (CABO). The MEC is control and backdrafting from fossil- likely to become less accurate in time, no longer being updated, and is being fuel-burning appliances. DOE has been however, as states adopt new codes. replaced by the International Energy preparing the final rule based on com- Thus, there will be continual updates. Conservation Code (IECC). The CABO ments received on the proposed rule Printed copies of the State Building requirement for one- and two-family and expects to issue it in 1999. DOE Codes Database are available for $15 by dwellings is being replaced in the year is also preparing a code compliance calling 1-800-270-CODE. To view the

62 BIPV Basics status of a particular state’s energy This exhaust can combine with sun- Atrium systems — BIPV is a glass ele- codes, select a state from the list online baked atmospheric dust to reduce the ment that provides different degrees (see http://www.energycodes.org/ amount of light that can reach the of shading and can be designed to states/ states.htm). The status of the modules and thus reduce system per- enhance indoor thermal comfort as state energy codes can be found at formance. Such systems may require well as daylighting. http://www.bcap.com . periodic cleaning with chemical agents to maximize the system's electrical out- Awning and Shading systems — A vari- Maintenance put. Consequently, system designers ety of PV materials can be mounted onto a facade in aesthetic manner to PV has no recurring fuel costs, and it must ensure adequate access to the serve as awnings. is promoted as a simple energy technol- system to perform these maintenance activities. ogy that is durable and relatively main- Roofing systems — The BIPV system tenance-free because it has no moving Failure-related maintenance involves displaces conventional roofing materi- parts. However, designers should repairs and replacements associated als such as tiles, shingles, and metal ensure that BIPV installations allow with poor performance or failures of roofing. easy access for inspecting, repairing, the BIPV system. This can be covered and replacing components. Mainten- The cost of a BIPV system depends under traditional and extended ance costs can be divided into two cate- on the type of system and the PV warranties. gories: preventive and failure-related. technology used in manufacturing it. Warranties Currently, only a few U.S. manufactur- Preventative maintenance can ensure ers produce custom and standardized the performance of a BIPV system. BIPV systems are generally covered BIPV products. For commercial and Shadowing on the PV array caused by a limited 12-month replacement institutional structures and buildings, by the natural or built environment warranty that guards against defects the two primary types of BIPV prod- reduces system output. Sunlight and ensures system repair and product ucts, facades and roofing materials, are reflects off expanses of sand, snow, replacements or an optional full refund available for both new construction and ice, and other light surfaces, and can of the purchase price. In case of an acci- refurbishment projects. increase output by reflecting additional dent, such as a fire, ancillary damage to solar energy onto arrays. However, a BIPV system may be covered by a BIPV Facade Systems — BIPV facade other structures, trees, and bushes near conventional building insurance policy. systems include laminated and pat- a BIPV system can inhibit solar access terned glass, spandrel glass panels, and and thus reduce system performance. Currently, the major PV manufacturers curtain wall glazing systems. These This is in turn detrimental to the offer power production warranties for BIPV products can displace traditional economic performance of the system. as long as 10, 20, and 25 years. These construction materials. Laminated glass manufacturers will replace the power is a standardized BIPV product. It is In the case of building retrofits, land- output lost from modules that fail to composed of two pieces of glass with scaping can often shade parts of a roof produce at least 80% of the minimum PV solar cells sandwiched between and limit solar access, so landscape power output specified on the back of them, an encapsulant of ethylene-vinyl architecture must be considered, and the module. This warranty dates from acetate (EVA) or another encapsulant trees must be trimmed periodically. the sale of the product to the original material, and a translucent or colored purchaser and is generally nontrans- tedlar-coated polyester backsheet. It The electrical performance of a BIPV ferrable. Other suppliers also offer can also be made with only one piece system can also be affected by accumu- optional warranties on roofing through of glass and a tedlar backsheet. lations of dirt on the modules. In most service and maintenance contracts. Architects can specify the color of the locations, normal rainfall removes the tedlar backsheet. layers of dust and pollution that can BIPV Products accumulate on the outer surface. Where These are the types of BIPV systems Spandrel panels are the opaque glass there is little rainfall, occasionally commercially available: used between floors in commercial spraying the system with water from glass building facades. A glazed curtain a standard garden hose to remove Facade systems — The BIPV system is wall is a non-load-bearing exterior wall dirt and debris is adequate but not designed to act as an outer skin and suspended in front of the structural required. weather barrier as part of the building frame and wall elements. Patterned or envelope. An example is a BIPV system fritted glass is semitransparent with The performance of a BIPV system can used for rainscreen overcladding. Glass distinctive geometric or linear designs. decline if it is located in a particularly BIPV products are typically used as dirty urban environment. Layers of facade systems. grime, caused by fuel exhaust and other emissions, can accumulate on a system.

BIPV Basics 63 PIX08462 Solar Design Associates, Inc./PIX04472 Solar Design

Figure 1. AC PV modules, Solar Design Associates Figure 2. Architectural PV glazing system, Innovative Design, Inc. FIRST, Inc./PIX03612 FIRST, Tim Ellison, ECD/PIX04473 Tim

Figure 3. PV-integrated modular homes, Fully Figure 4. Rooftop PV systems, Energy Conversion Independent Residential Solar Technology, Inc. Devices, Inc.

Some companies sell custom-made Curtain wall laminates are available for Flexible thin-film amorphous silicon BIPV glazing products, available in any both AC and DC power. The AC panel BIPV shingles can replace asphalt size or dimension and consisting of any has its own mini-inverter attached to shingles. This BIPV product is nailed to PV technology (crystalline or thin film). the back of the laminate. The AC the roof deck, very much the way that The architect can indicate the spacing PowerWall™ operates with current at traditional asphalt shingles are attached between solar cells, which will deter- maximum power with 2.0 amps (A) to a roof. This technology was designed mine the power supply and also permit and 110 volts (V). The DC PowerWall™ as a 2-kilowatt peak (kWp) BIPV sys- the design of passive solar features by operates at maximum power with 3.5 A tem for the Southface Energy Institute regulating the amount of daylighting and 68.4 V. The PowerWall™ generates in Atlanta, Georgia. Also available allowed to enter into the builiding. 250 watts (W) under standard test are fiber cement PV roofing shingles These products can be used in any com- conditions (STC). measuring 16 in. (40 cm) by 12 in. mercial glazing application. Standard (30 cm) by 1/4 in. (0.6 cm) and weigh- and custom products are available in BIPV Roofing Systems — Roofing sys- ing 5 pounds (2.27 kg). Crystalline sili- many sizes (as large as 1.3 m x 1.7 m) tems include BIPV shingles, metal con cells are laminated to fiber cement and in a range of thicknesses (0.5 mm roofing, and exterior insulation roof roofing shingles and are rated at 11 W to 2.5 mm glass). systems. These BIPV products can dis- of power output under STC. place traditional construction materials.

64 BIPV Basics BIPV metal roofing can replace an has brought together PV and building funding additional projects in 1997 architectural standing seam. The thin- product manufacturers in a coordinated under a second program known as film amorphous silicon PV material is effort to develop PV roofing shingles, PV:BONUS Two. laminated directly onto long metal facade glazing, and curtain wall prod- roofing panels. The BIPV metal roofing ucts for buildings and other structures. PV:BONUS (June 1993 – May 1999). The panels, with edges turned up, are laid Today there is a recognizable commer- five projects originally funded by the side by side and a cap is placed over the cialization trend toward standardizing PV:BONUS program have all been suc- standing edges to form a seam. These BIPV construction products. In the long cessfully installed in demonstration metal panels can be installed by a tradi- run, product standardization will be an projects, and most are now commer- tional roofer followed by an electrician. essential element in reducing the cost cially available to the buildings indus- of manufacturing BIPV systems. The try. These new technologies include the As an exterior insulation BIPV roof sys- following section on new construction following. tem, PV laminates are attached to poly- materials for buildings was extracted • AC photovoltaic module and curtain styrene insulation, and it provides from a paper written by Sheila J. wall application (Figure 1) thermal insulation rated R-10 or R-15. Hayter, P.E. (NREL) & Robert L. Martin It rests on the waterproof membrane (DOE). This paper, titled "Photovoltaics • Architectural PV glazing system without penetrating or being mechani- for Buildings, Cutting Edge PV," was (Figure 2) cally fastened to the building. In an presented at the UPEX conference in interlocking tongue-and-groove assem- 1998. Below is the section on Building • Dispatchable PV peak-shaving bly, the panels are weighed down by Opportunities in the U.S. for Photo- system pavers that surround the system to voltaics (PV:BONUS). provide access for maintenance and • PV-integrated modular homes repairs. Channels or raceways are The U.S. Department of Energy demon- (Figure 3) designed to provide access to the elec- strates its commitment to supporting trical connections. This technology can new PV-for-buildings technologies by • Rooftop BIPV standing-seam systems be used to redo the roof of an existing awarding Cooperative Agreement (Figure 4). building, as demonstrated by the New funding to U.S. manufacturers and AC Photovoltaic Module and Curtain York Power Authority on a community organizations for product develop- Wall Application. The product devel- center in Tuckahoe, New York. ment. These agreements are within the oped for this PV:BONUS project was a Additionally, the PV portion of the Building Opportunities in the U.S. for large-area PV module with a dedicated, product can be tilted up to 12° to help Photovoltaics (PV:BONUS) program. integrally mounted, direct-current (DC) optimize the system's orientation. The objective of the PV:BONUS pro- to alternating-current (AC) power gram is to develop technologies and to inverter (Figure 1). The module is This system can be installed on built- foster business arrangements that inte- designed to be integrated into the up and single-ply membranes of flat grate photovoltaics or hybrid products vertical facades and sloped-roof commercial roofs and typically weighs into buildings cost-effectively. Cost- construction of residential, commercial, 4 lb/ft2 versus 10 lb/ft2 for a conven- effectiveness, either through design; or institutional buildings. Large spaces tional aggregate ballast roof. Any PV integration (i.e., components, system, between the PV cells can be incorpo- technology can be applied in this pro- and/or building integration); dedicated rated into the module design to allow cess and will provide power according end-use applications; or technology direct sunlight to transmit through the to its solar cell and system efficiency bundling (i.e., PV/thermal hybrids) is module. The building designer can use rating. a major factor in selecting PV:BONUS this feature to enhance daylighting and projects. DOE is interested in products The manufacturer claims that this provide passive solar heating to the that can replace commercial building product extends normal roof life by space adjacent to the modules. Solar products and be installed without the protecting insulation and membranes Design Associates, Inc., led develop- necessity for specialized training. The from ultraviolet (UV) rays and water ment efforts for this project. Other team ultimate goal of the PV:BONUS pro- degradation. It does this by eliminating members included Mobil Solar Energy gram is market demonstrations of com- condensation because the dew point Corp., New England Electric, New mercially viable products that lead to is kept above the roofing membrane. York Power Authority, Pacific Gas and manufacturer commitments to pursue Electric, Kawneer, Maryland Energy production and sales. BIPV Product Development Administration, and Baltimore Gas Since the early 1990s, the U.S. Depart- In 1993, the U.S. Department of Energy and Electric. ment of Energy's (DOE's) Photo- awarded cooperative agreements for Architectural PV Glazing System. A voltaics: Building Opportunities in the five PV:BONUS projects. The success system of matching building facade United States (PV:BONUS) program of this initial effort resulted in DOE glazing products including opaque,

BIPV Basics 65 semitransparent, and clear units was this PV:BONUS project was to design divided into four categories: 1) glazing developed. A large-area, thin-film PV a line of modular solar homes that products; 2) roofing materials; 3) PV/ module option was available for the include photovoltaic power. To meet thermal (PV/T) hybrid systems; and opaque and semitransparent units. The this objective, it was necessary to mini- 4) other related projects (inverter tech- system was incorporated into the over- mize construction costs of the home so nology, fire retardancy investigations, head glazing of a demonstration project that the higher cost of the PV system and development of a "mini-grid"). in an Applebee’s Neighborhood Grill could be absorbed into the overall cost At the completion of Phase I, seven of and Bar in Salisbury, NC (Figure 2). The of the home. The effort was lead by these projects were selected for contin- designers placed a high-absorptance Fully Independent Residential Solar ued Phase II funding. Phase II is cur- metal pan approximately 1 in. (2.5 cm) Technologies, Inc. (FIRST, Inc.), a rently under way and the following below the back of the panel to increase non-profit organization teamed with projects are being pursued: effectiveness for solar heating of the air Bradley Builders and Avis America behind the panels. Fans operated by the (a builder of manufactured homes). • PV-powered electrochromic windows PV system drew the heated air through • Thin-film PV product line an air-to-water heat exchanger to Rooftop Photovoltaic Systems. The result of this PV:BONUS project was reduce the restaurant’s energy demand • Hybrid PV/thermal collector for producing hot water. Drawing hot the development of residential and air off the back of the PV panels also light-commercial PV-integrated roofing • Ballast-mounted PV arrays increased the operating efficiency of materials. These amorphous-silicon the panels. Although the manufacturer modules are manufactured either to • PV string inverters of the PV panels and leader of this resemble asphalt shingles or to be lami- • Field-applied PV membrane PV:BONUS team, Advanced Photo- nated onto metal standing-seam roof modules (Figure 4). One of the goals of voltaic Systems (APS), is no longer in • PowerRoofTM 2000. existence, the PV technology the com- the project was to develop a product pany developed continues to be used that required no special training to PV-Powered Electrochromic Windows. by the PV industry. Innovative Design install the PV-roof on actual buildings. Sage Electrochromics, in conjunction partnered with APS to design the These products have been tested in with Solarex, proposes to develop and Applebee’s system. demonstration projects and are now commercialize photovoltaic (PV) pow- commercially available. The leader ered electrochromic (EC) "smart win- Dispatchable PV Peak Shaving of this development team, Energy dows." EC windows control the amount System. A fully integrated dispatchable Conversion Devices, Inc., worked of sunlight and solar heat by dynami- peak-shaving system for commercial with United Solar Systems Corp., the cally switching between darkened and applications was designed for this National Association of Home Builders, clear states and anywhere in between. PV:BONUS project. The focus of the Solar Design Associates, Inc., and a They provide an opportunity to realize project was to reliably control the PV number of utility companies, construc- energy savings and reduce peak system output for a prescribed length tion companies, government agencies, electrical demand in buildings. The of time by including battery storage and educational institutions to design, low-power DC voltage required to with the PV system. The dispatchable manufacture, and test this product. power the EC window glazing will be system made it possible to displace a supplied by PV solar cells incorporated PV:BONUS Two (September 1997 – early load greater than the array’s output in the double-pane insulating glass unit 2000s). PV:BONUS Two activities are during peak demand periods. This fea- (IGU) so that no external hard-wired being carried out in three phases. Phase ture is especially important in commer- connections are needed. cial buildings where the peak demand I was the concept development and period often extends beyond the period business planning phase. Prototype Thin-Film Photovoltaics. With the of peak power production of the PV systems will be developed and tested support of subcontractors Kawneer, system. Delmarva Power and Light in Phase 2, the product and business Solar Design Associates, Inc., and Company was responsible for this development phase. Product demon- Viracon, Solarex will develop building- PV:BONUS effort. stration and marketing will occur in integrated photovoltaic products using Phase 3. It is expected that viable prod- tandem-junction amorphous silicon PV-Integrated Modular Homes. ucts will be offered commercially dur- modules. Major objectives of the pro- Installing residential photovoltaic sys- ing Phase 3. Participation in Phases 2 gram include: 1) developing a commer- tems onto homes constructed in a fac- and 3 depend on the accomplishments cial photovoltaic curtain wall module tory along with other energy-efficient of the previous phases. (Spandrel Module); 2) developing a features result in reducing the total commercial photovoltaic sunshade for The U.S. Department of Energy construction cost of the manufactured curtain walls (PowerTint Window); awarded 17 Phase I cooperative homes to be comparable to typical site- and 3) developing a light-transmitting built homes (Figure 3). The objective of agreements. These project areas were

66 BIPV Basics must exist for the ballast-mounting and fabric roofing systems. The approach to succeed. Ascension UNI-SOLAR PV Membrane will be Technology has already developed a shipped directly to the site for field ballast-mounting system for PV arrays. application or to a building product The system is applicable for both new company for integration with its own and retrofit construction on flat or products. The membrane uses United nearly flat roofs, typically on commer- Solar Systems Corp.’s multijunction cial buildings. a-Si stainless steel PV cells laminated in flexible UL-approved PV String Inverters. Advanced Energy materials.

Solar Design Associates, Inc./PIX06429 Solar Design Systems, Inc., proposes to design and manufacture a low-cost string inverter PowerRoofTM 2000. PowerLight system (SIS), which will minimize the Corporation, in cooperation with cost of the BOS components (i.e., the AstroPower, Solarex, BP Solar, and inverter and the PV output circuit Siemens Solar, proposes to develop an wiring). The SIS is an inverter and innovative building-integrated PV associated wiring that is designed to roofing system called PowerRoofTM operate with a single string of photo- (Figure 6). PowerGuard® is the first voltaic (PV) modules. By using a single core product in the PowerRoof family string, the need for an expensive string- and has been successfully developed combiner is eliminated. The paralleling under prior programs. The PowerRoof of multiple strings is accomplished by 2000 proposal targets the development Figure 5. PV sunshades at the State the utility or AC side of the system, of two next-generation core PowerRoof University of New York, Albany which can result in inexpensive instal- building products, HeatGuardTM and lation costs. PowerThermTM. Each builds upon the photovoltaic module and incorporating proven technological approach of the it into the curtain wall product. Field-Applied PV Membrane. United PowerGuard solar electric roofing Solar Systems Corp., in collaboration system. Hybrid Photovoltaic/Thermal with Energy Conversion Devices, Inc., Collector. Solar Design Associates, Inc., the National Association of Home Other PV for Buildings Products on United Solar Systems Corporation, Builders, Phasor Energy, Arizona Public the Market and on the Horizon. and SunEarth, Inc., propose to design, Service, Southern California Edison Building designers have shown great develop, demonstrate, manufacture Co., Southern Cal Roofing, ATAS interest in the new PV-for-buildings and commercialize a hybrid flat-plate International, Elk Corp., and San Diego systems, as indicated by the number of photovoltaic/thermal (PV/T) collector Gas & Electric intend to develop a participants in BIPV workshops for to deliver both electricity and thermal field-applied, flexible photovoltaic architects sponsored by DOE, the energy. The PV/T collector design (PV) membrane product for the 'built- American Institute of Architects (AIA), will employ a liquid thermal transfer environment." UNI-SOLAR PV Roll and other organizations. In general, medium and closely resemble conven- Membrane is a tional flat-plate solar thermal collectors flexible PV lami- in size, appearance, installation, and nate designed for a function. However, in place of the range of market normal thermal absorber plate, it will applications, such employ a PV element of triple-junction as covered parking amorphous silicon alloy solar cells structures, "flat" made with United Solar's proprietary roof commercial UNI-SOLAR technology, in which the buildings, archi- material and thermal characteristics tectural and struc- are well suited for combined PV/T tural metal roofing Power Light Coproration/PIX04471 applications. (including new Ballast-Mounted PV Arrays. Ascension construction and Technology will develop analytic and retrofit, flat, and experimental capabilities for quantify- curved roofs), ing the balance between driving (wind, facades, prefabri- seismic) forces and the restraining cated stress skin panel production, Figure 6. PowerLight roof on Tuckahoe Community (gravitational/frictional) forces that Center

BIPV Basics 67 building designers want PV systems PV modules will be close to that of Other products are designed to be used that can be integrated into the building high-end glass products, making it in flat-roof commercial retrofit applica- envelope and blend well with other easier for designers to justify the cost tions. They include an insulated unit building envelope components and of PV. with PV integrated into the top layer materials. Many of the products that and a roof membrane product with PV have been or are being developed with Designers are beginning to integrate integrated into the membrane. assistance from the PV:BONUS photovoltaics into sunshade building Program meet these criteria. components. Sunshades are used to The cutting-edge PV products dis- reduce the direct solar gain into a build- cussed in this paper are only an exam- New products such as transparent ing, which also reduces the building ple of what is available or expected to thin-film PV modules, for which the cooling loads (Figure 5). The angle of become available for buildings applica- designer can specify the transmissivity, the sunshade can also be set to optimize tions. This is not an exhaustive list, are expected to become commercially the output of the PV/sunshade system. however. available in the near future. The designer will be able to specify both Several PV-roofing products are Source: Sheila J. Hayter, P.E., and view glass and curtain wall PV now commercially available. One Robert L. Martin, "Photovoltaics for modules, so that the entire facade of crystalline-silicon-cell product replaces Buildings, Cutting Edge PV," presented a building can be clad in PV. Manu- traditional roofing materials and is at the Utility PV Experience Conference facturers predict that the price of these usually used in new construction. & Exhibition, October 1998.

68 BIPV Basics BIPV Terminology Building-integrated photovoltaics (BIPV) is a relatively recent new application of photovoltaic (PV) energy technologies. These are some of the basic terms used in describing PV technologies, BIPV products, and their uses:

Antireflection coating — a thin coating of a material that reduces light reflection and increases light transmission; it is applied to the surface of a photovoltaic cell.

Balance of System (BOS) — Non-PV components of a BIPV system typically include wiring, switches, power conditioning units, meters, and battery storage equipment (if required).

Bypass diode — a diode connected across one or more solar cells in a photovoltaic module to protect these cells from thermal destruction in case of total or partial shading of individual cells while other cells are exposed to full light.

Conversion efficiency — Amount of electricity a PV device produces in relation to the amount of light shining on the device, expressed as a percentage.

Curtain wall — an exterior wall that provides no structural support.

Encapsulant — Plastic or other material around PV cells that protects them from environmental damage.

Grid-connected — Intertied with an electric power utility.

Inverter — Device that transforms direct-current (DC) electricity to alternating- current (AC) electricity.

Module — Commercial PV product containing interconnected solar cells; modules come in various standard sizes and can also be custom-made by the manufacturer.

PV array — Group or string of connected PV modules operating as a single unit.

PV laminate — Building component constructed of multilayers of glass, metal or plastic and a photovoltaic material.

PV solar cell — Device made of semiconductor materials that converts direct or diffuse light into electricity; typical PV technologies are made from crystalline, polycrystalline, and amorphous silicon and other thin-film materials.

Solar access — Insolation incidence of solar radiation that occurs on a PV system’s surface at any given time; it determines the potential electrical output of a BIPV system.

Stand-alone — Remote power source separate from an electric utility grid; a stand-alone system typically has a battery storage component.

BIPV Terminology 69 Kiss, G.; Kinkead, J. (1995). Optimal Schoen, T.; Prasad, D.; Toggweiler, P.; Bibliography Building-Integrated Photovoltaic Eiffert, P.; and Sorensen, H. (1997). Applications. NREL/TP-472-20339. “Building with Photovoltaics—The Benemann, J. (1993). "Energy Active Golden, CO: National Renewable Challenge for Task VII of the IEA PV Facades." Solar Energy in Architecture Energy Laboratory. Power Systems Program.” Proceedings of and Urban Planning, Proceedings from the EC Photovoltaic Energy Conference, the Third European Conference on Kiss, G.; Kinkead, J.; Raman, M. (1995). Vienna. Architecture, 17–21 May, Florence, Italy; Building-Integrated Photovoltaics: A Case pp. 239–241. Study. NREL/TP-472-7574. Golden, Shugar, D.S. (1990). "Photovoltaics in CO: National Renewable Energy the Utility Distribution System: The Berdner, J.; Whitaker, C.; Wenger, H.; Laboratory. Evaluation of System and Distribution Jennings, C.; Kern, E.; Russell, M. Benefits." Proceedings from the Institute (1994). "Siting, Installation and Perfor- Maycock, P.D. (1994). "International of Electrical and Electronics Engineers: mance Issues for Commercial Roof- Photovoltaic Markets, Developments The Conference Record of the Twenty-First Mounted PV Systems." IEEE First and Trends: Forecast to 2010." Renewable Photovoltaic Specialists Conference, Vol. II; WCPEC, Dec. 5–9, Hawaii; pp. 981–985. Energy,Vol. 5, Part I; pp. 154–161. pp. 836–843.

Carlisle, N.; Taylor, P. Eiffert; Crawley, Murphy, A. (1998) Pacific Northwest Sick, F.; Erge, T. (eds). (1996). A. Sprunt. (1997). "Federal Efforts to National Laboratory. Personal commu- Photovoltaics in Buildings. IEA Task 16. Implement Renewable Energy nication. See also http://www.energy- London: James & James. Projects." Proceedings of the American codes.org/meccheck/ Solar Energy Annual Conference, April Taylor, P.; Becker, M.; Ezell, L. (1997). 25-30, Washington, DC. National Renewable Energy "Technical Assistance for New Federal Laboratory. (1997). Solar Electric Buildings Case Study: Smithsonian Dinwoodie, T.L.; Shugar, D.S. (1994). Buildings: An Overview of Today’s Institution Air and Space Museum "Optimizing Roof-Integrated Applications (Revised). DOE/GO-10097- Dulles Center." Energy & Environmental Photovoltaics: A Case Study of the 357. Produced for the U.S. Department Visions for the New Millennium. PowerGuard‰ Roofing Tile." IEEE of Energy. Golden, CO: NREL. Proceedings of the 20th World Energy First WCPEC; Dec. 5–9, Hawaii; pp. Engineering Congress, Nov. 19–21. 1004–1007. National Renewable Energy Laboratory. (1994). Solar Radiation Data U.S. Department of Energy. (1998). Eiffert, P. (1998). An Economic Manual for Flat-Plate and Concentrating Federal Technology Alert: Photovoltaics. Assessment of Building Integrated Collectors. NREL/TP-463-5607, DOE/GO-10098-484. Washington, DC: Photovoltaics. Ph.D. Dissertation, DE93018229. Golden, CO: NREL, April. US DOE, April. Oxford Brookes School of Architecture. Paradis, A.; Shugar, D.S. (1994). U.S. Department of Energy. (1995). Goodman, F.R., Jr.; Schaefer, J.C.; "Photovoltaic Building Materials." Solar Tapping Into the Sun. DOE/CH10093- Demeo, E.A. (1995). "Terrestrial, Grid- Today, Vol. 8, No. 3, May/June; pp. 203-Rev1, DE93000075. Washington, Connected Systems: Field Experience, 34–37. DC: US DOE, April. Status, Needs, and Prospects." Solar Cells and Their Applications, ed. Larry D. Polansky, M.; Gnos, S. (1993). Walker, H., et al. (1997). "Building Partain. NY: John Wiley & Sons, Inc. "Introduction to a New Factory Integrated Photovoltaic System: The Building with Photovoltaic Facades and Thoreau Center for Sustainability." Hayter, S. J., PE; Martin, R. L. (1998). Photovoltaic Skylights That Cover 70% Proceedings of the American Solar Energy "Photovoltaics for Buildings, Cutting of the Total Energy Requirements." Annual Conference, April 25–30, Edge PV." Paper presented at UPEX, Proceedings of the Third European Washington, DC. San Diego, California, p. 10. Conference on Architecture, 17–21 May, Florence, Italy; pp. 254–256. Wenger, H.; Eiffert, P. (1996). "The International Energy Agency (1995). Architect’s Perspective on the Use of PV Power. The Netherlands: Novem, Schoen, T.J.N. (1994). "An Introduction PV in Buildings: Questionnaire March. to Photovoltaics in Buildings." Results." Building Energy Proceedings, Proceedings of the Third International 1st Solar Electric Building Conference, Kalin, T.J. (1994). "PV as [a] New Workshop on Photovoltaics in Buildings, March 4–6, Boston, Massachusetts. Architectural Element." Proceedings September, Cambridge, Massachusetts, of the 12th European Photovoltaic Solar Section 1; pp. 1–9. Energy Conference, 11–15 April, Amsterdam, The Netherlands; pp. 1847–1853.

70 Bibliography Appendix A: International Activities

"Building with Photovoltaics — The Challenge For Task VII Of The IEA PV Power Systems Program" by T. Schoen1, D. Prasad2, P. Toggweiler3, P. Eiffert4 and H. Sørensen5

1: Ecofys Energy and Environment, P.O. Box 8408, NL-3503 RK Utrecht,

2: National Solar Architecture Research Unit, UNSW, Sydney NSW 2052, Australia,

3: ENECOLO, Lindhofstrasse 13, CH-8617 Mönchaltorf, Switzerland

4: National Renewable Energy Laboratory, Center for Energy Analysis and Application, 1617 Cole Blvd, Golden, CO 80401, USA,

5: Esbensen Consulting Engineers, Teknikerbyen 38, DK-2830 Virum, Denmark Abstract On January 1, 1997, a new Task started within International Energy Agency’s Photovoltaic Power Systems (IEA PVPS) Program: Task VII. The objective of Task VII is to enhance the architectural quality, the technical quality and the economic viability of PV systems in the built environment and to assess and remove non-technical barriers to their introduction as an energy-significant option. The value of building integration for the introduction of grid-connected PV is recognized around the world. Rooftop programs, aiming at large-scale application in the next century, are carried out in many countries. In order to reach this widespread application, however, cost reductions still are essential. BIPV research and development should therefore focus on achieving these cost reductions, by optimizing integration concepts, by developing new building products and by the development of standardized products.

Building-integrated PV does more than offer perspectives for the next century. PV systems are installed today by building owners who appreciate the added value of solar roofs and facades, and who are willing to pay a premium for PV. This market potential must be captured and assisted. From the research and development side, this can be done by focusing on architectural issues and on non-technical barriers that impede short-term market penetration. The work in Task VII concentrates on all these aspects. The Task VII research and development strategy is to enhance systems technologies, to work on the architecture of building integrated PV, and to assess and remove non-technical barriers that impede the widespread application of PV in the built environment.

Note: One ECU is approximately equivalent to one U.S. dollar.

Appendix A: International Activities 71 INTRODUCTION THE COSTS OF BIPV in the last five years, it can be estimated that these cost reductions will be It is generally expected that in the next Figure 1 gives the breakdown of the reached within only a few years, indi- century, photovoltaics will be able to average costs for building-integrated cating that BIPV will rapidly become contribute substantially to the main- PV systems, though estimates vary interesting and competitive. stream power production, even though from country to country. PV now is up to five times more expen- PV, well integrated into the architec- As can be seen in this figure, the costs sive than grid power. tural design of the building, can for building integration currently range enhance the aesthetics of the building In densely populated areas, such as from 30% to 50% of the total system and give the property owner a 'green' major parts of Europe, Japan and the costs. Reduction of module costs will and self-sufficient image. Owners of US, large-scale realization of systems enlarge the need for attention to opti- commercial buildings are increasingly will only be possible through distrib- mal building integration, i.e., reducing more interested in installing PV sys- uted PV systems in the urban environ- the costs for substructures, mounting tems as a high-value feature of their ment since no land is available for the and wiring to the absolute minimum. property. Projects are being realized installation of ground-based systems. with limited or no government support Rooftop programs in Japan (70,000+), In order to achieve widespread applica- at all, indicating that cost reductions of US (1,000,000) and Europe (1,000,000) tion of PV as a competitive power a mere 25% to 50% are sufficient for illustrate the worldwide attention given source, PV electricity must be produced opening up the market. to building-integrated PV. at the level of 0.05 to 0.10 ECU per kWh (5¢ to 10¢). From Fig. 1, it can be seen The housing market is increasingly sen- Integration of PV into buildings offers that even for Italy, this would require sitive for this 'added value' of the PV cost advantages that make this concept cost reductions by a factor 3 to 4. In the system; house owners are willing to attractive for urbanized regions as well Netherlands, cost reductions by a factor pay a premium price for a PV-clad as for less densely populated areas with 10 or more are required. house, thereby generating additional sufficient unoccupied land available. funding for the PV system. PV installations can be installed on Here is where the major challenge lies for R&D programs in the field of surfaces of buildings and along roads The AC module system seems to be BIPV: cost reductions are essential for or railways, with the possibility to very attractive for this type of applica- large-scale introduction of building- combine energy production with other tion. Property developers in the integrated PV systems. R&D should functions of the building or non- Netherlands have shown interest in focus on these cost reductions. building structure. Compared with introducing PV systems consisting of large-scale, ground-based PV power 4 AC modules on a regular basis in the plants, cost savings through these com- PV FOR THE FUTURE — building programs, if the prices are bined functions can be substantial, e.g., PV FOR TODAY reduced to 5 ECU ($5) per Wp. This in expensive facade systems where In addition to cost reduction opportuni- makes PV a technology not just for the cladding costs may equal the costs of ties as previously mentioned (such as future but also for today. the PV modules. replacement of building materials and avoidance of land use), building inte- The challenge of national programs as Additionally, no high-value land is gration offers interesting cost benefits. well as international actions, such as required, and no separate support If PV systems are installed as decentral- Task VII, is to assist these emerging structure is necessary. Electricity is gen- ized power systems on buildings, and markets by developing photovoltaics erated at the point of use. This avoids if net metering is used for selling back into a cost-effective and clean power transmission and distribution losses surplus power to utilities, PV electricity source, available for application in dis- and reduces the utility company's will only have to be produced at contributed systems of utilities, builders, capital and maintenance costs. sumer tariff prices, ranging from 0.10 to and cities of the future as well as today. R&D should therefore not only address Following the advantages of building 0.20 ECU per kWh. For the Netherlands long-term developments for large-scale integration, more and more countries this implies required cost reductions application as a bulk power source, but view distributed PV as a power source by a factor of 3 to 5. For Italy, cost also short-term application as competi- with a large potential for the future and reductions by a factor of 2 to 3, or in tive feature of the built environment. are correspondingly starting to con- the optimistic scenario, a 50% cost The integration of PV into architecture struct and operate building-integrated reduction would be sufficient for and the building market are important PV systems on a large scale [1]. market introduction. issues in such an R&D strategy. Given the cost reductions that have been achieved by BIPV R&D programs

72 Appendix A: International Activities standards and guidelines, and the PV costs, ECU/Wp PV electricity costs, ECU/kWh study of economic aspects and other (U.S. $/Wp) (U.S. $/kWh) market factors that impede the wide- 8 0.8 Mounting and spread application of PV in buildings. 7 installation 0.7 02527250m 6 0.6 In brief, Task VII will work on R&D in Substructure the following fields: 5 0.5 Cabling 4 0.4 (1) BIPV technologies Inverters 0.3 3 (2) PV and architecture 2 Modules 0.2 1 0.1 (3) Non-technical barriers 0 0.0 BIPV Technologies NL NL IT IT (NL = Netherlands; IT = Italy.) The technologies that are now available for the integration of PV into buildings Figure 1. Overview of BIPV system costs in ECU/Wp (left) and the resulting are, in general, too expensive for large- PV electricity costs in ECU/kWh (right), for different countries and scale introduction. Cost reductions calculation methods (optimistic: maximum performance ratio, low interest are thus still essential. They can be rate; pessimistic: average performance ratio, high interest rate). achieved by carefully redesigning the Note: Currently, the ECU is equivalent to one U.S. dollar. PV support structure, and by integrating the PV system into well-known building components such as the pre- Upscaling of the near-term BIPV mar- energy-significant option. This objec- fabricated roof or the structural-glazing ket will, moreover, be possible only if tive reflects the R&D strategies men- facade. non-technical barriers that impede the tioned earlier. application of BIPV are addressed and Development of standardized dealt with successfully. The major bar- The primary focus of Task VII is on the PV/building units integration of PV into the architectural rier to overcome here could well be the The development of low-cost, flat roof- involvement of builders and building design of (roofs and facades of residential, commercial, and industrial) build- mounting elements such as the Sofrel owners in the design and implementa- [3] show that, through careful redesign tion of building integrated PV. R&D, ings and other structures in the built environment (such as noise barriers, of substructures from the low-cost as well as pilot and demonstration point of view, cost reductions up to projects, should work on the achieve- parking areas, and railway canopies). Also important are the market factors, 50% are possible for substructure and ment of this involvement as well as mounting costs. A similar strategy on the removal of other non-technical both technical and non-technical, that need to be addressed and resolved could be applied in the development of barriers such as the lack of information, mounting structures for sloped roofs confidence, or appropriate financing before wide adoption of PV in the built environment will occur. and facades. PV facades in general still mechanisms. use tailor-made solutions, suitable only R&D STRATEGIES FOR Essential for the success of Task VII is for custom-made modules, requiring the active involvement of urban plan- case-by-case engineering and installa- TASK VII ners, architects, building engineers, tion by specialists, which lead to high- In recognition of the potential of and the building industry. Task VII is quality but high-price solutions. building-integrated PV to the develop- very keen on the collaboration between ment and introduction of photovoltaics, these groups and PV system specialists, For new buildings, integration of stan- IEA's PV Power Systems Program in utility specialists, the PV industry, dard PV modules into low-cost, every- January 1997 launched a new task: Task and other professionals involved in day cladding systems is required, VII - PV in the Built Environment. photovoltaics. whereas for existing buildings, low-cost add-on systems offer good cost per- The objective of Task VII is to enhance The joint effort will consist mainly of spectives. In order to make mounting the architectural quality, the technical the evaluation and development of concepts suitable for application in the quality, and the economic viability of innovative concepts for the integration vast number of existing buildings with PV systems in the built environment of PV into the built environment, the a poor energy balance, add-on systems and to assess and remove non-technical demonstration of integration concepts, should include extra thermal insulation barriers to its introduction as an contribution to the development of layers.

Appendix A: International Activities 73 Integration of PV modules and It should, however, be noted that the barrier. A number of R&D actions are cells into standard building application of custom-made PV prod- discussed here. materials ucts has economic consequences. The costs of modules can go down substan- Development of The integration of PV into well-known tially if they are produced in bulk. At a financing schemes building materials, such as roof tiles, production level of 500 MWp per year, is under way. Attention to these devel- The availability of appropriate financ- costs of less than 1 ECU ($1) per Wp are opments around the world shows the ing mechanisms in Germany and achievable with today's technologies cost reduction potential of this R&D Switzerland has been shown to have a [5]. This cost level will not be reached path. major impact on the introduction of PV. with tailor-made modules produced In Germany, rate-based incentives have Optimal tuning of PV modules to exist- on a smaller scale. led to a substantial increase in the PV ing building materials can result in sub- market, with annual growth figures The challenge for the PV R&D com- stantial reduction of mounting and larger than ever (1996: 3 MW;1997: munity, together with architects and substructure costs. In the end, these 10 MW) [6]. builders, is to develop high-quality costs might be fully omitted through integration concepts that can make the integration of PV cells into building The assessment of such financing use of the low-cost potential of bulk- materials. Similar attempts are being schemes, tailored to the specific needs produced modules. made in the field of stand-alone PV sys- of individual countries, will be one of the key activities of Task VII. tems, where PV cells are being inte- As a first activity, Task VII has dealt grated into bus shelters, vessels, and with the evaluation of existing BIPV Integration into the other applications. projects. The result is a list of architec- building process tural quality criteria for BIPV projects Integration of PV into (please see Table 1). If PV is to become a well-accepted tech- prefabricated building elements nology readily available for architects, This R&D path is especially suitable Using these criteria in the design of the building industry, and property for countries where the prefabricated new projects and integration concepts owners, integration concepts will have buildings and building components are based on standard modules can to meet regular building quality stan- commonly used (e.g., the Netherlands, enhance the architectural quality of dards. This can be achieved by fully Japan). Preliminary research indicates BIPV without introducing high-cost integrating the PV system into building that cost reductions up to 50% (com- (custom-made) products. materials and by integrating the con- pared with that of today's technology) struction process of BIPV systems into through prefabrication are possible [4]. Non-Technical Barriers the building construction process. As mentioned above, a number of non- Building integration must include inte- PV and Architecture technical barriers exist that impede gration into the contractual framework the implementation of PV in buildings. and the organizational structure of Market enhancement requires accep- building projects. tance of PV by builders, architects, and Assessment and removal of these barri- users. Full integration into architecture ers will result in enhancement of both Building integration also must include is therefore essential. the near-term and the long-term PV integration into the regular quality market. A preliminary listing of barriers schemes for building components. The physical characteristics of PV prod- has been prepared by ucts for integration in buildings must Task VII. Task VII will meet architectural requirements for work on the analysis of Table 1: Architectural criteria for the review of color, size, and these market barriers, PV buildings and integration products materials. Products that meet these followed by recom- • Natural integration and visually acceptable requirements are being developed mendations for their around the world. Cells are available removal. • Architecturally pleasing and visually pleasing in different colors and textures; modules can be produced to the designer’s As can be expected, • Good composition between materials and colors specification. budgetary constraints are the main barrier. • Fit the grid, harmony, composition These developments have certainly The removal of other assisted the creation of high-end, high- barriers, however, • Appropriately links with the context of the project quality examples of building-integrated will most certainly help PV. They are thus very important to the overcome this prime • Well-engineered and designed introduction of BIPV. • Innovative new design

74 Appendix A: International Activities FINAL REMARKS The aforementioned R&D directions are reflected in the projected activities of Task VII. It can, therefore, be concluded that Task VII can contribute to the further development and implementation

Tim Ellison, ECD/PIX04473 Tim of PV in the Built Environment. The success of Task VII will of course depend on the effectiveness of the international collaboration and on the contributions of the participating countries to the overall framework of the Task.

The coming five years will show if Task VII can achieve its challenging objective. All experts in the countries participating in Task VII are requested to closely follow the task and, where appropriate, collaborate in its work. REFERENCES [1] Palz, W., and Van Overstraeten, R. (1995). Strategic Options for PV Development in Europe. In: Figure 2: The National Association of Home Builders 21st Century Proceedings of the 13th EC Townhome at the National Research Home Park in Bowie, Maryland, USA; Photovoltaic Energy Conference, 883–886. it is one of the Task VII projects to be evaluated. [2] Barnes, H. (ed) (1997). Photovoltaic PV will be largely accepted by builders, taken into account from the very start power systems in selected IEA architects, and end-users only if the of the building process, where the first member countries. EA Technology, quality of BIPV systems fully meets the decisions have a major impact on the Capehurst Chester, UK. requirements of everyday construction ways to include PV in the building (e.g., elements. the orientation of the building). Tools [3] Toggweiler, P., Ruoss, D., Roecker, C., for shaping and sizing of the PV system Bonvin, J., Muller, A., and Affolter, P. The development of such quality can range from intricate software pack- (1997). Sofrel flat roof system and first schemes is a part of the work of Task ages (linked to the overall energy installation. In: Proceedings of the VII as well as an import issue of the design tools) to easy aids as an irradia- 14th EC Photovoltaic Energy European BIPV programs. As an exam- tion disk. Conference, 701–704. ple, the Joule PRESCRIPT project aims at the development of guidelines and R&D is required in both energy plan- [4] Boumans, J.H. and Schoen, T. (1996). pre-standards for the testing and certifi- ning and the design and sizing of PV Prefab Energy-roof — trends and cation of building-integrated PV [7]. systems, within the overall design of developments. Ecofys, Utrecht, the the energy system of the building. Netherlands. Training and education PV can be included in building projects Concerning education, 'PV at schools' [5] Bruton, T.M, e.a. (1997). A study of the only if architects and principals have programs have proven to be successful Manufacture of 500 Wp p.a. of sufficient knowledge about PV tech- in a number of European countries [8]. Crystalline Silicon Photovoltaic nologies and appropriate design tools In order to teach the architects, Modules. In: Proceedings of the 14th to assist them. builders, and occupants of the future EC Photovoltaic Energy Conference, how to work with PV, integration of PV 11–16. Design tools can range from planning into educational programs at all levels instruments to tools for shaping and is important. A follow-up of national sizing the PV systems. Planning instru- activities at the European level could ments are required to ensure that PV is enhance this process.

Appendix A: International Activities 75 [6] Gabler, H., Heidler, K., and Hoffmann, V.U. (1997). Market Introduction of Grid-Connected Photovoltaic Installations in Germany. In: Proceedings of the 14th EC Photovoltaic Energy Conference, 27–32.

[7] Van Schalkwijk, M., Hoekstra, K.J., Schoen, T., and Van der Weiden, T.C.J. (1997). Quality Assurance of PV Integration in Buildings: Experiences from Practice and Future Outlook. In: Proceedings. of the 14th EC Photovoltaic Energy Conference, 1616–1619.

[8] Nordmann, T. (1995). The Swiss 1 MWp PV-School Demonstration Program. In: Proceedings of the 13th EC Photovoltaic Energy Conference, 894–897.

76 Appendix A: International Activities Appendix B: Contacts for International Energy Agency Photovoltaic Power System Task VII — Photovoltaics in the Built Environment

Australia Spain Deo Prasad Nuria Martin [email protected] [email protected]

Austria Sweden Reinhard Haas Mats Andersson [email protected] [email protected]

Canada Switzerland Per Drewes Christian Roecker [email protected] [email protected]

Denmark Peter Toggweiler Henrik Sorensen [email protected] [email protected] United Kingdom Germany David Lloyd Jones Hermann Laukamp [email protected] [email protected] Donna Munro Netherlands [email protected] Henk Kaan [email protected] Paul Ruyssevelt [email protected] Bert Middelman [email protected] United States Patrina Eiffert Tjerk Reijenga [email protected] [email protected] Steven Strong Tony Schoen [email protected] [email protected]

Appendix B: Contacts for International Energy Agency Photovoltaic Power System Task VII 77 Appendix C: Design Tools

Dru Crawley, DOE Program Manager for Building Energy Tools, has established a Building Energy Software Tools Directory. This directory is available on the Internet online; see http://www. eren.doe.gov/buildings/tools_directory/.

Software building design tools are divided into categories that include Energy Simulation, Utility Evaluation, Energy Economics, Atmospheric Pollution, Envelope Systems, Solar Climate Analysis, Codes and Standards: Development and Compliance, and Load Calculations. The software tools described in this section may be particularly useful to those designing buildings and other structures into which photovoltaic power systems are integrated.

78 Appendix C: Design Tools AWNSHADE BEES overall performance score. Default values are provided for all of this This program calculates the unshaded A powerful technique for selecting cost- Windows-based input. fraction of a rectangular window for effective, environmentally preferable any given solar position coordinates building products, BEES (Building for Output: Summary graphs depicting relative to the window. Calculations are Environmental and Economic Sustain- life-cycle environmental and economic made for window shading configura- ability) is based on consensus stan- performance scores for competing tions, including awnings, with or with- dards. The Windows-based decision building product alternatives. Detailed out side walls or overhangs of arbitrary support software, aimed at designers, graphs are also available, depicting dimensions above the window. builders, and product manufacturers, scores for the six environmental Awnshade can also calculate the includes actual environmental and eco- impacts underlying the life-cycle envi- unshaded fraction for a sequence of nomic performance data for a number ronmental performance score, and solar positions. It calculates the effec- of building products. depicting first and future costs underly- tive unshaded fraction of diffuse sky ing the life-cycle economic performance BEES measures the environmental per- irradiance or illuminance incident on score. Graphs are live in the sense that formance of building products by using the window, assuming uniform sky alternative graph types (pie graph, bar the environmental life-cycle assessment radiance/luminance, and the effective graph, etc.) may be displayed; rows and approach specified in the latest versions ground-reflected unshaded fraction. It columns may be moved; colors, labels, of ISO 14000 draft standards. All stages can handle cases in which shadows of and other display attributes may be in the life of a product are analyzed: the side of the awning/overhang cross customized; and graphs may be raw material acquisition, manufacture, the top of the window. printed. transportation, installation, use, Audience: This is for architects, building recycling, and waste management. Computer Platform: Windows 95 or designers, building energy perfor- Economic performance is measured higher personal computer with a 486 mance simulators. using the American Society for Testing or higher microprocessor, 32 megabytes and Materials (ASTM) standard life- or more of RAM, at least 10 megabytes Expertise Required: Basic understanding cycle cost method, which covers the of available disk space, and a 3.5-in. of building shading geometry. costs of initial investment, replacement, floppy diskette drive. The program- operation, maintenance, repair, and Input: User-friendly I/O screens, ming language is CA Visual Objects. disposal. Environmental and economic describing geometry of windows, performance are combined into an Strengths: The program offers a unique awnings, and vertical side fins. overall performance measure using the blend of environmental science, deci- Output: Results can be printed directly ASTM standard for Multi-Attribute sion science, and economics. It uses to a printer, saved to a print file, or Decision Analysis. For the entire BEES life-cycle concepts, is based on consen- saved to files formatted for importing analysis, building products are defined sus standards, and is designed to be into graphic plotting programs. and classified according to the ASTM practical, flexible, and transparent. It is standard classification for building practical in its systematic packaging of Strengths: Outputs a table of unshaded elements known as UNIFORMAT II. detailed, science-based, quantitative fractions for a range of incident sun environmental and economic perfor- directions. Audience: This is for designers, speci- mance data in a manner that offers fiers, builders, product manufacturers, useful decision support. It is flexible Weaknesses: No fancy graphics of win- researchers, and policy makers. in allowing tool users to customize dow shadows or their movement across judgments about key study parameters. Expertise Required: None; there were the window. It is transparent in documenting and more than 500 users in the first 6 providing all the supporting perfor- Availability: Awnshade version 2.0 is months of availability, both in the U.S. mance data and computational available from the contact at a cost of and abroad. algorithms. $45 (including shipping and handling). Input: The user sets relative importance Weaknesses: It includes environmental Contact: weights for (1) synthesizing six envi- and economic performance data for Joanne Stirling, Document Sales Office ronmental impact scores (global warm- only 24 building products covering Florida Solar Energy Center ing, acid rain, nutrification, resource 12 building elements. 1679 Clearlake Road depletion, indoor air quality, solid Cocoa, Florida 32922-5703 waste) into an environmental perfor- Availability: BEES 1.0 software and Telephone: 407- 638-1414 mance score; (2) discounting future printed documentation available free Facsimile: 407-638-1439 costs to their equivalent present value; of charge through the EPA Pollution E-mail: [email protected] and (3) combining environmental and Prevention Information Clearinghouse Online: http://www.fsec.ucf.edu economic performance scores into an at 202-260-1023 or via e-mail, Appendix C: Design Tools 79 [email protected]. BEES was Output: More than 50 user-selected, version has links to a Schematic developed by the NIST Green Buildings formatted reports printed directly by Graphic Editor and two simplified Program with support from the EPA BLAST; the REPORT WRITER program simulation tools, one for daylight and Environmentally Preferable Purchasing can generate tables or spreadsheet- one for energy analyses. Program. ready files for more than 100 BLAST variables. Audience: Architects and engineers Contact: working in early building design Barbara C. Lippiatt Strengths: PC Format has Windows phases. National Institute of Standards and interface as well as structured text Technology interface; detailed heat balance algo- Expertise Required: Knowledge of Office of Applied Economics rithms allow for analysis of thermal Windows applications; there are at least 100 Bureau Drive, Stop 8603 comfort, passive solar structures, high 200 users. Gaithersburg, Maryland 20899-8603 and low intensity radiant heat, mois- Input: Graphic entry of basic building Telephone: 301-975-6133 ture, and variable heat transfer coeffi- geometry and space arrangements. Facsimile: 301-975-5337 cients æ none of which can be analyzed Default descriptive and operational E-mail: [email protected] in programs with less rigorous zone characteristics can be edited by user. Web: http://www.bfrl.nist.gov/oae/ models. bees.html Output: User-selected output parame- Weaknesses: High level of expertise ters displayed in graphic form, includ- required to develop custom system and BLAST ing 2-D and 3-D distributions. plant models. This program performs hourly simula- Computer Platform: PC-compatible, tions of buildings, air handling sys- Availability: Software prices range from Windows 95/98/NT, 30 megabytes of tems, and central plant equipment in $450 for an upgrade package to $1500 hard disk space; the programming order to provide mechanical, architec- for new installations. This package language is C++. tural, and energy engineers with accu- contains complete sources, almost 400 rate estimates of a building's energy weather files, numerous documents Strengths: It allows comparisons of mul- needs. The zone models of BLAST about using BLAST as well as docu- tiple design solutions with respect to (Building Loads Analysis and System mentation (all on CD ROM). Contact multiple descriptive and performance Thermodynamics), which are based on the Building Systems Laboratory for parameters. It also allows the use of the fundamental heat balance method, additional information. sophisticated analysis tools from the are the industry standard for heating early, schematic phases of building and cooling load calculations. BLAST Contact: design, and does not require the user to output may be utilized in conjunction Building Systems Laboratory have in-depth knowledge to use linked with the LCCID (Life Cycle Cost in University of Illinois tools for energy, daylighting, and other Design) program to perform an eco- 1206 West Green Street analyses. nomic analysis of the building, system, Urbana, Illinois 61801 and plant design. Telephone: 217-333-3977 Weaknesses: Version 1.0 is linked to Facsimile: 217-244-6534 simplified tools for daylight and Audience: Mechanical, energy, and E-mail [email protected] energy analyses. architectural engineers working for Online: http://www.bso.uiuc.edu architectural-engineering firms, con- Availability: Version 1.0 is available at sulting firms, utilities, Federal agencies, BUILDING DESIGN ADVISOR the Web site below. research universities, and research labo- This provides a software environment ratories. Contact: that supports the integration of multi- Konstantinos Papamichael ple building models and databases Expertise Required: High level of com- Lawrence Berkeley National used by analysis and visualization puter literacy not required; engineering Laboratory tools, through a single, object-based background helpful for analysis of air- Mail Stop 90-3111 representation of building components handling systems. 1 Cyclotron Road and systems. Building Design Advisor Berkeley, California 94720 Input: Building geometry, thermal char- (BDA) acts as a data manager and Telephone: 510-486-6854 acteristics, internal loads and sched- process controller, allowing building Facsimile: 510-486-4089 ules, heating and cooling equipment designers to benefit from the capabili- E-mail: [email protected] and system characteristics. Readable, ties of multiple analysis and visualiza- Web: http://kmp.lbl.gov/BDA structured input file may be generated tion tools throughout the building by HBLC (Windows) or the BTEXT design process. BDA is implemented as program. a Windows-based application. The 1.0

80 Appendix C: Design Tools CLIMATE CONSULTANT DOE-2 DOS, VMS; the programming language is FORTRAN. This program graphically displays cli- This is an hourly, whole-building mate data in dozens of categories useful energy analysis program calculating Strengths: Detailed, hourly, whole- to architects. These include tempera- energy performance and life-cycle cost building energy analysis of multiple tures, wind velocity, sky cover, percent of operation. It can be used to analyze zones in buildings of complex design; it sunshine, psychrometric chart, the energy efficiency of given designs is widely recognized as the industry timetable of bioclimatic needs, sun or the efficiency of new technologies. standard. charts, and sun dials showing hours Other uses include utility demand-side when solar heating is needed and when management and rebate programs, Weaknesses: A high level of user knowl- shading is required. The psychrometric development and implementation of edge and computer literacy is required. analysis recommends the most appro- energy efficiency standards and com- priate passive design strategy as out- pliance certification, and training a new Availability: The cost is $300 to $2000, lined in Givoni, Man, Climate and corps of energy-efficiency-conscious depending upon the hardware platform Architecture (ref. date). It also develops building professionals in architecture and software vendor. the kind of data incorporated in Watson and engineering schools. Contact: and Labs, Climatic Design (ref. date). Audience: Architects, engineers in pri- Fred Winkelmann Audience: Architects, students of vate A&E firms, energy consultants, Lawrence Berkeley National architecture. building technology researchers, utility Laboratory companies, state and Federal agencies, Mail Stop 90-3147 Expertise Required: Intended to be self- and university schools of architecture 1 Cyclotron Road instructional, the program requires and engineering. Berkeley, California 94720 only basic familiarity with computers Telephone: 510-486-5711 and architectural vocabulary. Expertise Required: A high level of com- Facsimile: 510-486-4089 puter literacy is required; a 5-day ses- E-mail: [email protected] Input: Typical Meteorological Year sion of formal training in basic and Web: http://gundog.lbl.gov (TMY) weather data in short format. advanced DOE-2 use is recommended. There are 800 user organizations in EMISS Output: Graphic plots of weather data. the United States and 200 user organi- This software generates a file of local Strengths: Highly graphic, user-friendly. zations internationally; user organiza- air-pollution emission coefficients. It tions consist of 1 to 20 or more is used with the BLCC life-cycle cost Weaknesses: Requires weather data in individuals. program to estimate reductions in emis- TMY weather data format. sions associated with energy conserva- Input: Hourly weather file plus tion projects. Three types of emission Availability: Not copy protected; sharing Building Description Language input factors are currently included: carbon is encouraged. It is most easily aquired describing geographic location and dioxide, sulfur dioxide, and nitrous by copying a disk or by downloading building orientation, building materials oxide. Emissions factors are specified off the Web; otherwise, users can send a and envelope components (walls, win- separately for six different end-use check to the technical contact for $35, dows, shading surfaces, etc.), operating energy types: electricity, distillate and payable to the Regents of the schedules, HVAC equipment and con- residual fuel oil, natural gas, liquid University of California. trols, utility rate schedule, building petroleum gas, and coal. It is distrib- component costs. The program is avail- uted in connection with the BLCC Contact: able with a range of user interfaces, life-cycle cost program to several thou- Professor Murray Milne from text-based to interactive/graphi- sand users. Department of Architecture and Urban cal windows-based environments. Design Audience: Federal energy managers Box 951467 Output: Twenty user-selectable input and energy coordinators; engineers University of California at Los Angeles verification reports, 50 user-selectable and architects; budget analysts and Los Angeles, California 90095-1467 monthly/annual summary reports, and planners. USA user-configurable hourly reports of 700 Telephone: 310-825-7370 different building energy variables. Expertise Required: None required. Facsimile: 310-825-8959 E-mail: [email protected] Computer Platform: PC-compatible; Sun; Input: Regional or local emissions fac- Online: http://www.aud.ucla.edu/ DEC-VAX; DECstation; IBM RS 6000; tors or fuel-specific end-use data. energy-design-tools NeXT; 4 megabytes of RAM; math coprocessor; compatible with UNIX,

Appendix C: Design Tools 81 Output: Preformatted tables of com- Expertise Required: A moderate level of hot water, daylighting with windows, puted emission factors by type of fuel. computer literacy is required; two days daylighting with skylights, photo- of training are advised. voltaics, solar thermal electric (para- Strengths: Emission factors for fossil bolic dish, parabolic trough, central fuels can be regionalized or localized. Input: Only four inputs are required to power tower), wind electricity, small Program contains state-specific electric- generate two initial generic building hydropower, biomass electricity (wood, ity emission factors and U.S. average descriptions. Virtually everything is waste, etc.), and cooling load avoidance sulfur content of fossil fuels as default defaulted but modifiable. User adjusts (multiple glazing, window shading, data. A users guide is included as file descriptions as the design evolves, increased wall insulation, infiltration with program. using fill-in menus, including utility- control). Life-cycle cost calculations rate schedules, construction details, comply with 10 CFR 436. Weaknesses: The quality of the emissions materials. factors depends on the user's knowl- Audience: Building energy auditors. edge of the factors that contribute to Output: Summary table and 20 graphi- these emissions. cal outputs are available, generally Expertise Required: Must be able to comparing current design with base gather summary information on build- Availability: Free to Federal agencies case. Detailed tabular results are also ing and installation energy use pat- through the Energy Efficiency and available. terns; intended for use by trained Renewable Energy Clearinghouse, auditors; results should be interpreted 1-800-DOE-EREC (363-3732). Strengths: Fast, easy-to-use, accurate. by someone familiar with the limita- Automatic generation of base cases tions of the program. Contact: and energy-efficient alternate building Linde Fuller descriptions; automatic application of Input: Summary energy load data; solar National Institute of Standards and energy-efficient features and rank- and wind resource data provided in a Technology ordering of results; integration of day- database indexed by ZIP code; biomass Office of Applied Economics lighting thermal effects with thermal and solid waste resource data must be Building 226, Rm B226 simulation; menu display and modifi- gathered by the auditor. Gaithersburg, Maryland 20899 cation of all building-description and Telephone: 301-975-6134 other data. Output: Annual cost and energy sav- Facsimile: 301-208-6936 ings; life cycle economics; a red flag if E-mail: [email protected] Weaknesses: Limited to smaller build- an option is viable; viable options Online: http://www.eren.doe.gov/ ings and HVAC systems that are most ranked by savings-to-investment ratio. femp/ often used in smaller buildings. Strengths: Establishes consistent ENERGY-10 Contact: methodology and reporting format for Passive Solar Industries Council a large number of audits in varying This is a design tool for smaller residen- Suite 600 locations and with varying building tial or commercial buildings (e.g., those 1511 K Street, NW use types; sophisticated analyses of that are less than 10,000 square feet in Washington, DC 20005 technology performance and cost floor area) or buildings that can be Telephone: 202-628-7400 while keeping data requirements to a treated as one- or two-zone increments. Facsimile: 202-393-5043 minimum. The software performs a whole-build- Online: http://www.psic.org/ ing energy analysis for 8760 hours energy10.htm Weaknesses: Provides only first-order per year, including dynamic thermal screening, to focus design; requires and daylighting calculations. It is FRESA more detailed feasibility analyses on specifically designed to facilitate the applications most likely to be cost-effec- This is a first-order screening tool to evaluation of energy-efficient building tive; requires high level of knowledge identify potentially cost-effective appli- features in the very early stages of the about energy audits and the limitations cations of renewable energy technology design process. of the program; not suitable for general on a building and facility level. FRESA use. Audience: This is for building designers, (Federal Renewable Energy Screening especially architects; HVAC engineers; Assistant) is useful for determining Availability: Available from the technical utility companies; university schools which renewable energy applications contact. of architecture and architectural require further investigation. Tech- engineering. nologies represented include active solar heating, active solar cooling, solar

82 Appendix C: Design Tools Contact: depict power usage by day, week, or program CD-ROM includes a climate Andy Walker, Ph.D. month. Variables include kilowatts at database of 239 locations in the conti- National Renewable Energy Laboratory a minimum and may include kilovars nental United States, Alaska, Hawaii, 1617 Cole Boulevard and kilovolt-amperes, if the source data Puerto Rico, and Guam and a World- Golden, Colorado 80401 file contains this information. wide Hourly Climate Generator Telephone: 303-384-7531 Program that generates hourly climates Facsimile: 303-384-7411 Strengths: Identifies, by time of day, for 2,132 global locations from monthly E-mail: [email protected] periods of excessive power demand data. The SolarPro 2.0 solar water heat- Online: http://www.eren.doe.gov/ and consumption. Also useful in bench- ing program is also included. Six types femp/techassist/softwaretools/ marking a facility's power usage before of panel surface tracking are incorpo- softwaretools.html energy measures are implemented and rated into the program: fixed slope and tracking the results after implementa- axis, tracking on a horizontal east-west IDEAL tion. Ability to immediately utilize axis, tracking on a horizontal north- more than 25 data formats without This software is designed to read elec- south axis, tracking on a vertical axis prior conversion of the data by the user. tronic data records of facilities’ electri- with a fixed slope, tracking on a north- south axis parallel to the Earth's axis, cal energy use; the data records are Weaknesses: Limits analysis to month- and continuous tracking on two axes. compiled by electric utility companies by-month studies. Can produce records Panel shading information can also be and normally used internally only for suitable for greater-than-one-month input. billing purposes. Upon request, the analysis using conventional spread- utility will release the data to the cus- sheets. Must use DOS sequences for Audience: This program is for PV sys- tomer for analysis purposes. These printing reports and graphs. tem design professionals, architects, data records are formatted in more than engineers, energy offices, universities, 25 distinct file types identified thus far. Availability: Download demos from and students. IDEAL (Interval Data Evaluation and the Web to determine suitability to task. Analysis of Load) translates all these Price negotiable based on number of Expertise Required: Knowledge of elec- formats into a common database and copies; list price $1,000. trical design, PV basics. produces informative graphs and reports to assist the user, the energy Contact: Input: Windows 95-based interface; management team, or consultants in John D. Helms uses the electrical system load by hour quickly identifying periods of serious PC Application Systems for weekdays, weekends, and holidays; power mismanagement. Extensions to 4310 Twin Pines Drive requires panel type from database, the basic program will perform power Knoxville, Tennessee 37921-5143 number of parallel connections and bill calculations, time-of-use analysis, Telephone: 423-588-7363 series strings of similar panels; battery temperature and humidity plots, and Facsimile: 423-584-1350 backup charging parameters; AC optimum standby generator sizing and E-mail: [email protected] inverter requirements; and climate file. run times. Online: http://ourworld.compuserve. com/homepages/john_helms/ Output: Solar Fraction charts by month, Audience: Industrial and large com- battery states of charge by month (max- mercial accounts who have electronic PV-DesignPro imum, average, minimum), annual metering on their electrical power ser- This program simulates photovoltaic performance table (energy produced, vice (typically, loads with more than system operation on an hourly basis for necessary backup, and states-of- 500 kilowatts demand, and virtually all one year, based on a user-selected cli- charge), prospective cash-flows of pur- with time-of-use metering). mate and system design. PV-DesignPro chased and sold energy, system costs, is recommended for designs that costs of backup energy, prices of sold Expertise Required: No special expertise include battery storage, which can be energy, maintenance and replacement required. either stand-alone systems with genera- costs, and the estimated life of the system. A rate of return is calculated, as Input: Data file, normally obtained from tor backup or utility-interconnected well as an overall price per kWh of the the electric utility company, which systems. The purpose of the program system and payback years. includes interval recordings of power is to aid in photovoltaic system design by providing accurate, in-depth infor- usage. Program requires data to be an Strengths: Most information needed for mation on the likely system power ASCII-formatted data file on diskette. PV designs is included in databases. output and load consumption, backup Output: Both detailed and summary power needed during system opera- Weaknesses: Resistive loads, such as reports of facility electrical usage. More tion, and the financial impacts of water pumping with a motor only, than 70 preformatted graphs visually installing the proposed system. The cannot currently be modeled.

Appendix C: Design Tools 83 Relatively high level of PV expertise Weaknesses: No private-sector tax analy- contact for $35, payable to the Regents recommended. sis included. of the University of California.

Availability: CD-ROM, $149.00 + $10.00 Availability: Free to Federal agencies Contact: shipping and handling. Price includes through the Energy Efficiency and Professor Murray Milne Worldwide Hourly Climate Generator Renewable Energy Clearinghouse, Department of Architecture and 1.0 program and SolarPro 2.0 solar 1-800-DOE-EREC (363-3732). Urban Design water heating program. See Web site Box 951467 or call for more information. Contact: University of California at Los Angeles Linde Fuller Los Angeles, California 90095-1467 Contact: National Institute of Standards and Telephone: 310-825-7370 Mike Pelosi Technology Facsimile 310-825-8959 PV-DesignPro Software Office of Applied Economics E-mail: [email protected] P.O.Box 1043 Building 226, Rm B226 Online: http://www.aud.ucla.edu/ Kihei, Maui, Hawaii 96753 Gaithersburg, Maryland 20899 energy-design-tools Telephone: 808-879-7880 Telephone: 301-975-6134 Facsimile: Facsimile: 301-208-6936 Florida Solar Energy Center E-mail: [email protected] E-mail: [email protected] 1679 Clearlake Road Online: http://www.maui.net/ Online: http://www.eren.doe.gov/ Cocoa, Florida 32922-5703 ~sandy/PV-DesignPro.html femp/techassist/softwaretools/ Telephone: 407-638-1414 softwaretools.html Facsimile: 407-638-1439 Quick BLCC E-mail: [email protected] This program is used to set up multiple SOLAR-2 Online: http://www.fsec.ucf.edu project alternatives for life-cycle costing This software plots sunlight penetrat- analysis in a single input file. The Quick ing through a window with any SOLAR-5 BLCC (Quick Building Life-Cycle Cost) combination of rectangular fins and This program displays 3-D plots of program provides a convenient method overhangs. It also plots an hour-by- hourly energy performance for the for solving relatively simple LCC prob- hour, three-dimensional suns-eye view whole building or for any of 16 differ- lems that require finding the lowest "movie" of the building. It prints annual ent components. SOLAR-5 also plots LCC design alternative among many tables of the percentage of the window heat flow into and out of thermal mass mutually exclusive alternatives for the in full sun, radiation on glass, and other as well as indoor air temperature, same project. Input data files are trans- data. output of the HVAC system, cost of ferrable to BLCC for more detailed electricity and heating fuel, and the analysis. Audience: This is for architects, students corresponding amount of air pollution. of architecture, building managers, and It uses hour-by-hour weather data. It Audience: Federal energy managers knowledgeable homeowners. contains an expert system to design and energy coordinators; engineers an initial base case building for any Expertise Required: Intended to be self- and architects; budget analysts and climate and any building type, which instructional, it requires only basic planners. an architect can copy and redesign. familiarity with computers and archi- Contains a variety of decision-making Expertise Required: Familiarity with tectural vocabulary. aids, including combination and com- present-value concept is helpful. Input: Window, overhangs, and fins parison options, color overlays, and bar Input: Initial investment costs; base- geometry. charts that show for any hour exactly year annual energy costs; maintenance, where the energy flows. repair, and replacement costs; time Output: Graphic plots, tables. Audience: This is for architects, students period. Strengths: User-friendly, highly graphic. of architecture, building managers, and Output: Preformatted tables of input knowledgeable homeowners. Weaknesses: Allows only rectangular data summary and LCC and compara- shading elements. Expertise Required: It is intended to be tive analyses results. Exportable data self-instructional, with built-in help files. Availability: Not copy protected; sharing options; requires only basic familiarity is encouraged. The software is most Strengths: Ideal for preliminary eco- with computers and with architectural easily aquired by copying a disk or by nomic evaluation of multiple design vocabulary. downloading off the Web; otherwise, alternatives. Users guide is included as users can send a check to the technical file with program.

84 Appendix C: Design Tools Input: From only four pieces of data SOMBRERO 5 days after it is first started up. The full initially required (floor area, number of version sells for $230. In designing both active (domestic hot stories, location, and building type), the water, photovoltaics) and passive solar expert system designs a basic building, Contact: energy systems, shading of collectors filling in hundreds of items of data; the Prof. Dr.-Ing. F.D. Heidt or windows by other objects plays an user can make subsequent revisions, Building Physics and Solar Energy important role. SOMBRERO provides usually beginning with overall building University of Siegen quantitive solutions to these problems. dimensions, window sizes, etc. Siegen, 57068 It calculates geometrical shading coeffi- Germany Output: Dozens of different kinds of cients, which can be used either directly Telephone: +49 271-740-4181 three-dimensional plots, tables, and for visualization or as quantitative Facsimile: +49 271-740-2379 reports. For example, displays heat gain input to other thermal simulation E-mail: [email protected]. or loss for more than a dozen different programs. d400.de building components; shows heat flow Web: http://nesa1.uni-siegen.de Audience: Architects, engineers for ther- into and out of the thermal mass of the mal simulations of buildings or solar building, as well as the output of the SUN POSITION plants. heating and air conditioning systems; The program calculates time series of displays air temperatures (outdoors or Expertise Required: Basic knowledge of sun angles (such as solar altitude and indoors) and air change rates; predicts geometry and solar radiation. solar azimuth) for a given location and the cost of heating fuel and electricity. outputs them as text files that can be Input: Three-dimensional objects are imported into spreadsheets and solar Strengths: Intended for use during built up by their boundary planes. Up energy analysis programs. Sun Position the very earliest stages of the design to 300 plane areas with 12 points each is highly customizable; it can calculate process (when most critical energy can be treated. Objects like houses and angles for one specific day, once a decisions are made); extremely user trees are predefined and described by month for one year, once a week, daily, friendly and rapid, calculating a full parameters like height, width, and etc., and in a given day calculate the year using TMY data in less than a position in space. Single planes are angles once a day, hourly, every 15 min- minute on a 486 MB machine. described by their vertex-points in the utes, etc. Its primary purpose is to assist two-dimensional co-ordinate system Weaknesses: Not intended for complex architects and solar designers. related to the plane itself (in case of mechanical system design or equip- rectangles simply by their length and Audience: Architects, passive solar ment sizing. height) and positioned by indication designers, PV and solar thermal energy Availability: SOLAR 5.4 is the most of azimuth, elevation, and origin in the system designers. recent public release, updated in three-dimensional space. Time steps Expertise Required: Understanding of September 1997. It writes out its own for simulation can be selected freely. fundamentals of sun angles (see users manual. Not copy protected; Foliage of trees and reflection factors www.crest.org/staff/ceg/sunangle/ sharing is encouraged. Most easily of the ground can be given as monthly for an introduction to sun angle aquired by copying a disk or by down- schedules. concepts). loading off the Web; otherwise, users Output: Values of the daily course of can send a check to the technical con- geometrical shading coefficients are Input: The user inputs the geographical tact for $35, payable to the Regents of calculated hourly. location, the frequency of the data the University of California. desired, and the output format desired; Computer Platform: MS-DOS 5.0 the program has a graphical user Contact: and MS-Windows 3.1 or better; PC- interface. Professor Murray Milne compatible system with VGA- Department of Architecture and compatible graphic-board (at least Output: The output is text files consist- Urban Design 640 x 480 pixels); about 5 MB free ing of tables of sun angle data; the Box 951467 space on hard disk. The programming specific sun angles, format of the data, University of California at Los Angeles language is Delphi. etc., are specified by the user. Los Angeles, California 90095-1467 Telephone: 310-825-7370 Strengths: Easy to handle. Computer Platform: Windows and Facsimile: 310-825-8959 Macintosh; the programming language E-mail: [email protected] Weaknesses: Unknown. is MacroMedia Director. Online: http://www.aud.ucla.edu/ energy-design-tools Availability: A demonstration version Strengths: Best for people performing can be downloaded free; it expires analyses of buildings or solar energy

Appendix C: Design Tools 85 systems over a year who need to know and heat transfer properties of win- to handle input of weather or other solar altitude and azimuth angles for dows in buildings. time-dependent functions and output their analysis. of simulation results. TRNSYS Audience: This is for architects, build- (TRaNsient SYstem Simulation Weaknesses: While Sun Position can ing designers, fenestration energy Program) is typically used for HVAC compute individual sun angles (i.e., at performance simulators, atmospheric analysis and sizing, solar design, build- one specific time instead of throughout scientists, and others interested in ing thermal performance, and analysis the year), it would be more efficient to determining the spectrum of radiation of control schemes. use the internet SunAngle calculator for from the sun and sky. single calculations. Audience: Engineers, researchers, and Expertise Required: Basic understanding architects. Availability: Free. of solar geometry. Expertise Required: None to use standard Contact: Input: User-friendly I/O screens, solar package; FORTRAN knowledge is help- Christopher Gronbeck position, atmospheric conditions. ful for developing new components Seattle Energy Works 1020 NE 68th Street Output: Results can be printed directly Input: TRNSYS input file, including Seattle, Washington 98115 to a printer, or saved to a print file or to building input description, characteris- Telephone: 206-729-5260 files formatted for importing into tics of system components and manner Facsimile: 206-522-5051 graphic plotting programs. in which components are intercon- E-mail: [email protected] nected, and separate weather data (sup- Strengths: Provides a solar spectrum Web: http://www.energysoftware. plied with program). Input file can be data file with columns for wavelength, com generated by graphically connecting direct normal, direct horizontal, direct components. SUNSPEC tilted, diffuse horizontal, and diffuse tilted spectral irradiances, as well as the Output: Life-cycle costs, monthly This software calculates clear-sky direct global (both direct and diffuse) versions summaries, annual results, histograms, beam and diffuse-sky solar spectral of these. Also outputs the integrated plotting of desired variables (by time irradiances and the sum of these two total irradiances in W/m2 and the total unit), online variable plotting (as the spectra for sun positions and atmos- integrated illuminances in lux for all simulation progresses). pheric conditions specified by the user. these beams. Sunspec also calculates the spectral Strengths: Because of its modular irradiances from the direct beam, dif- Weaknesses: Current menu of typical approach, the program is extremely fuse sky, or ground reflections that are atmospheric conditions is limited. It flexible for modeling a variety of ther- incident on an arbitrarily tilted plane. does not yet have the latest version of mal systems at different levels of Sunspec integrates these spectra to the SMARTS algorithm and is not as complexity; supplied source code determine the total irradiances, user-friendly as a planned future and documentation provide an easy illuminances, and luminous efficacies version. method for users to modify or add for each component. components not in the standard library; Availability: Sunspec 1.0 is available extensive documentation on compo- Sunspec offers the user a menu of typi- from the contact at a cost of $35 nent routines, including explanation, cal atmospheric conditions to choose (including shipping and handling). background, typical uses and govern- from and follows this with detailed ing equations; supplied time step, editing screens permitting the user to Contact: starting, and stopping times allow change any input parameter. The input Joanne Sterling, Document Sales Office choice of modeling periods. Version parameters include values for ozone Florida Solar Energy Center 14.2 moves all the TRNSYS utility pro- concentration, water vapor, turbidity, 1679 Clearlake Road grams to the MS Windows platform ground reflectance (albedo), solar alti- Cocoa, Florida 32922-5703 (95/NT), including a choice of graphi- tude and azimuth angles, and tilted Telephone: 407- 638-1414 cal drag-and-drop programs for creat- plane altitude and azimuth angles. Facsimile: 407-638-1439 ing input files, a utility for easily Sunspec includes a loop option permit- E-mail: [email protected] creating a building input file, and a ting repeated calculations at different Online: http://www.fsec.ucf.edu program for building TRNSYS-based solar positions for the same atmos- applications for distribution to pheric conditions. It also has an option TRNSYS nonusers. Web-based library of addi- for outputting solar spectral data files This modular system simulation soft- tional components and frequent down- that can be read by the Window 4 pro- ware includes many of the components loadable updates are also available. gram, which calculates the solar optical commonly found in thermal energy systems as well as component routines

86 Appendix C: Design Tools Weaknesses: No assumptions about the building or system are made (although default information is available) so the user must have detailed information about the building and system and enter this information into the TRNSYS interface.

Availability: Version 14.2, Commercial, $4000; Educational, $2000. Free demonstration diskette and information are available from the technical contact. International distributors are located in Germany, France, Belgium, and Sweden in addition to two distributors in the United States.

Contact: TRNSYS Coordinator Solar Energy Laboratory University of Wisconsin 1500 Johnson Drive Madison, Wisconsin 53706 Telephone: 608-263-1589 Facsimile: 608-262-8464 E-mail: [email protected] Online: http://sel.me.wisc.edu/ trnsys/download.htm

Appendix C: Design Tools 87 About the Authors

Patrina Eiffert, Ph.D. Gregory J. Kiss Dr. Eiffert is a project leader in the National Mr. Kiss, a specialist architect, has been a principal of Renewable Energy Laboratory’s (NREL’s) Kiss + Cathcart since 1984. His work has focused on Deployment Facilitation Center. NREL is a U.S. the integration of solar technologies into architecure Department of Energy (DOE) national laboratory. and product design, and has included built projects As a Deputy Team Leader within NREL’s Federal research and education. Kiss + Cathcart have won a Energy Management Program (FEMP) team, Dr. number of awards and invited competitions, includ- Eiffert has had experience managing projects that ing top prizes in every solar-architecture competition assist in implementing renewable energy in the since 1992. Kiss + Cathcart’s projects range from Federal sector. Primary activities range from con- first-of-a-kind photovoltaic buildings in Port Jarvis, ducting economic feasibility analysis and design New York, and Fairfield, California, to major PV studies through assessment and exploration of buildings projects in progress at Four Times Square alternative financing mechanisms. Dr. Eiffert leads in Manhattan, New York; in Yosemite National Park; national activities under the Save with Solar: Federal and in Hamburg, Germany. Participation in the Million Solar Roofs Initiative on behalf of DOE FEMP. Research by the firm has included three studies on building-integrated photovoltaics commissioned Additionally, Dr. Eiffert co-represents the United by NREL. In conjunction with Energy Photovoltaics States in the International Energy Agency, of Princeton, New Jersey, Kiss + Cathcart has devel- Photovoltaic Power Systems (PVPS) Task VII, oped several BIPV construction products, including Photovoltaics in the Built Environment, along with large-area lamiations for facades and skylights. The Steven Strong of Solar Design Associates. In this firm is also developing custom patterned, semitrans- position, as an internationally recognized expert in parent PV panels for building use. Building Integrated Photovoltaics (BIPV), Dr. Eiffert leads the effort to develop International Guidelines Consulting activities include the Whitehall Ferry for the Economic Evaluation of BIPV and is the Terminal project in New York and solar housing in Activity Leader for Subtask 3: Non-technical Winslow, Arizona, as well as the projects listed in Barriers. the design briefs in this book.

Dr. Eiffert completed her doctorate in Architecture Kiss + Cathcart designed "Under the Sun," a major on building-integrated photovoltaics at Oxford exhibition of solar design and architecture at the Brookes University Post-Graduate Research School Cooper Hewitt, National Design Museum, in the United Kingdom. Dr. Eiffert has authored Smithsonian Institution. The exhibit is an investiga- many articles and publications related to renewable tion of the design implications of the solar future; energy systems and programs and is a guest lecturer it was originally held in one of the most prestigious at universities across the country. garden sites in the United States. This is now a traveling exhibit. Patrina Eiffert NREL, M.S. 2723 Gregory J. Kiss 1617 Cole Blvd. 150 Nassau Street, Top Floor Golden, CO 80401-3393 New York, NY 10038

88 About the Authors NOTICE: This report was prepared as an account of work sponsored by an agency of the United States government. Neither the United States government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accu- racy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States government or any agency thereof. Available for a processing fee to U.S. Department of Energy and its contractors, in paper, from: U.S. Department of Energy Office of Scientific and Technical Information P.O. Box 62 Oak Ridge, TN 37831-0062 phone: 865.576.8401 fax: 865.576.5728 email: [email protected] Available for sale to the public, in paper, from: U.S. Department of Commerce National Technical Information Service 5285 Port Royal Road Springfield, VA22161 phone: 800.553.6847 fax: 703.605.6900 email: [email protected] online ordering: http://www.ntis.gov/ordering.htm Available electronically at http://www.doe.gov/bridge

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