Solar Structure for the University of Texas

UTSoA - Seminar in building integrated photovoltaics

Photovoltaic Application for the Scoreboard

Photovoltaic Application for the Scoreboard at Darrell K. Royal-Texas Memorial Stadium in Austin, Texas

The University of Texas at Austin School of Architecture

Gregory Arcangeli, M. Arch I Chad Gnant, M. Arch I Erin Holdenried, M. Arch I Vanessa Poe, M. Arch II Under Professor Werner Lang

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UTSoA - Seminar in Sustainable Design

Photovoltaic Application for the Scoreboard

i Table of Contents ii Executive Summary

5 The Solar Veil

1 Introduction

5.1 Solar

2 Photovoltaics 5.2 Structure 2.1 Types 5.3 Figures 2.1.1 Monocrystalline Photovoltaics 2.1.2 Polycrystalline Sillicon

5.4 Advantage/Disadvantage

2.1.3 Thin Film Photovoltaics

6 The Solar Cascade 2.1.4 Organic Solar Cells

2.2 Tracking Systems

6.1 Solar 6.2 Structure

3 Austin, Texas 3.1 Local Conditions

6.3 Figures 6.4 Marketing

3.1.1 Climate 3.1.2 Solar Support

3.2 The University of Texas 3.2.1 Campus Resources

4 Building Integration 4.1 The Longhorns 4.2 The Scoreboard 4.2.1 Orientation 4.2.2 Design Iteration

2

7 Call to Action 7.1 Special Thanks 7.2 Work Cited / References 7.3 Illustrations 7.4 Contacts 7.5 Appendix

UTSoA - Seminar in Sustainable Design

Photovoltaic Application for the Scoreboard

Executive Summary

The University of Texas at Austin School of Architecture Mission: In an effort to decrease The University of Texas at Austin’s dependence on nonrenewable energy, a group of Architecture graduate students are proposing an innovative, cost-effective, high-profile initiative that centers around one of the university’s most recognized attributes—athletics.

Description: The University of Texas at Austin is continually implementing new and inventive strides towards establishing a more sustainable environment. As “green” technologies surface, efforts are made to incorporate proponents of sustainability into the campus culture. In this proposed undertaking, one of our athletic icons, the scoreboard at the Darrell K. Royal- Texas Memorial Stadium, is the target.

The highly venerated scoreboard in the football stadium serves as a symbol of Texas pride and accomplishment. Unfortunately, the scoreboard also serves as an admonition of energy consumption. Our proposal is to transfigure the scoreboard into photovoltaics (solar cells), transforming it into a beacon of sustainability. Eighty-thousand plus attendees at every football game would be reminded not only of the university’s commitment to sustainability, but of their own personal responsibility to our planet.

Technologies: Photovoltaics are a stable source of energy that requires minimal maintenance over their lifespan. The installation of the photovoltaic system would establish The University of Texas at Austin as a leader in energy cost mitigation and renewable resource usage among the top research facilities in the nation.

Markets: Studies of Sustainability: As the world around us evolves into an eco-minded existence, the study of sustainability, from research to investment, will continue to grow.

It is crucial that our reputation as a university with measurable dedication, research and investment in sustainability grows with it. By intensifying our commitment to sustainability, we will attract the best and brightest minds in the field to the university.

Photovoltaic Training: As the demand for educated engineers and trained installers increases in the realm of photovoltaics, the university will be able to fill the demand by creating learning opportunities in all areas of solar energy study for our students.

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Photovoltaic Application for the Scoreboard

UTSoA - Seminar in Sustainable Design

Photovoltaic Application for the Scoreboard

Photovoltaic Application for the Scoreboard at Darrell K. Royal-Texas Memorial Stadium in Austin, Texas Gregory Arcangeli Chad Gnant Erin Holdenried Vanessa Poe

main picture of presentation

Figure 01: Full Stadium

1 Introduction

The University of Texas is a leader in both academic research and athletics in the US collegiate system. One major reason for the University’s success is that UT is an institution that looks at opportunities that will help it stand out amongst other universities as a leader.

This proposal seeks to provide information, evidence, and basic design concepts for the attachment of photovoltaic cells to the backside of the 7,370 square foot video screen nicknamed the “GodzillaTron” at the Darrell K. Royal-Texas Memorial Stadium (DKR-TMS).

Creating a visible symbol for the University’s position on for the of sustainable and renewable energy sources is the focus of this project. The DKR-TMS has an unobstructed view towards the capital building and the commercial districts of downtown. The DKR-TMS also is flanked by a major elevated US Interstate. Interstate 35 is the major freeway that connects San Antonio to Dallas-Fort Worth. Also on gameday, the solar array will be viewed around the US via television broadcast. All of these vantage points means it could be one of the most viable photovoltaic collectors in the nation.

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UTSoA - Seminar in Sustainable Design

2 Photovoltaics

Photovoltaic Application for the Scoreboard

Photovoltaics (PV) are solar collecting cells that create sunlight directly into energy. When the light strikes the PV cells electrons are dislodged thus creating electrical current. It is then converted from DC to AC current which can be used directly within the building, stored in batteries for later use, or be fed back into the grid. There are many different types of photovoltaics that have a wide range of energy production efficiencies and applications. The interest in this technology is steadily growing and new technologies are being invented and improved every day.

PVs are seen as personal power plants that are environmental friendly and are reliable by not having any moving parts or an exhaustible fuel source to run them. Each individual unit is called a cell and a series of cells together in a panel are called a module. Several panels in a series is called an array and the panels work together as one large energy generating surface. PVs are able to generate enough energy to power anything from a coffee pot to an entire city block of buildings. This technology has great possibilities for rural areas as well as in developing countries due to its . The cost of PV panels have decreased by 90% since the early 1970’s and will continue to become more financially feasible with the help of higher production, technological advances, and government rebates and incentives. “Photovoltaic production worldwide has been doubling every two years, increasing by an

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UTSoA - Seminar in Sustainable Design

Photovoltaic Application for the Scoreboard

Figure 03: Required Cells to create 1 kW

Figure 02: Available PV Efficiencies

average of 48% each year since 2002, making it the world’s fastest-growing energy technology1.�

Germany has dominated the Photovoltaic market, but the Unites States is projected lead the solar PV market by 2020. 2, 3

2.1 Types There are several types of PVs that are arranged into three groups arranged by production: first, second, and third generation. The first generation of PVs includes monocrystalline photovoltaics and polycrystalline photovoltaics. Monocrystalline was created from the waste of Silicon Valley and gets it’s name from the solid silicon ingot that was sliced to form the base of the cell. This type of PV has the highest efficiency out of all the generations, but currently has the highest price.

Polycrystalline photovoltaics are created from melting the waste particles from the production of monocrystalline and cast into a block where a specific heating process makes the silicon form large crystals. The block is cut into thin wafers and used in similar fashion to monocrystalline cells, but with less of energy efficiency. The second generation of photovoltaics includes thin film technology and features the application of 1 2 3

Kropp, Robert Usvat Corporation Energy Department G, John

photovoltaics onto flexible substrates. These substrates can bend and form to multiple curves and are opening up a wide range of possible applications from tent structures to clothing.

The third and final generation covers advanced photovoltaics and include organic solar cells.

This generation of cells is the more promising for future energy efficiencies but due to its low cost.

These three generations of PVs create a wide range of uses for multiple applications. Each PV has its own unique characteristics that make specific to a particular application. In our study we will be focusing on monocrystalline, thin film, and organic cells as possibilities for application onto the Scoreboard.

2.1.1 Monocrystalline Photovoltaics

Manufacturing Process: Monocrystalline photovoltaic crystals are not that much different in the initial manufacturing phase as semiconductor silicon (Si) processors that are found in most electronics today. The main difference is the purity of the silicon ingot that is created. The tolerances for purity are much smaller for semiconductor or electronics grade then solar cells commonly known as solar grade.

Solar cells can have impurities upwards of 1 to 2 % while electronics grade can only have only a

few billionths of a single percent. 4 The crucible (Czochralski) process has become the established method for manufacturing monocrystalline silicon cells. The polysilicon base material is melted into a quartz crucible where a seed crystal with a defined orientation is dipped into the melt and slowly drawn out into a cylindrical monocrystal. These monocrystals are cut into semi-round or square bars are then sawn into thin wafers, which are cleaned, diffused with phosphorous. An anti-reflective coating is applied and the current collector is printed on the front and the contacts on the back, in a screenprinting process. After the cells are etched to create a clear division between the conducting layers, the cells are ready to be connected in series into solar collecting modules.

Efficiency: The efficiency limit of photovoltaics is around 28 percent. Laboratory testing has created efficiency around 24 percent while standard commercial grade photovoltaics are around 1218 percent efficient. This difference is due to a couple of reasons. The first reason is partly do to the purity of the solar cell. The more pure the crystalline structure the higher the efficiency.

The other side is the higher the cost to produce making it less marketable to general public.

The second reason is losses of energy found in 4

Photovoltaics: Solar Electricity and Solar Cells...

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UTSoA - Seminar in Sustainable Design

Photovoltaic Application for the Scoreboard

Figure 05: Cost of the Photovoltaic Generations

Figure 04: Production of Monocrystalline and Polycrystalline Solar Cells

Figure 06: Monocrystalline and Polycrystalline Panel

the solar array. This is shading caused by the glass, light reflecting off the glass, losses in the transition and inverter. The main reason is the sun light itself. The chemistry of photovoltaic is such that not all wavelengths of sunlight activate the solar cell. Only a portion of this energy is at the right frequency to trigger the change.

structures have the most understood industry standards. This allows for quick installation of photovoltaic arrays on to existing buildings and integration into building skins.

Color: The color range is varied but most come in the form of dark blue or black. Other colors such as yellow are available. The darker the surface the darker more energy is captured, therefore colors such as yellow has a less efficiency then black or blue.

Malleability: Silicon crystalline structures are brittle and require reinforcement to protect them from breaking. This is typically provided by glass of 3mm in thickness on each side of the solar cell.

This limits the form these photovoltaic panels can take on in architecture. Products such as thin film technology have this ability but produce lower watts / sq meter.

Advantages and Disadvantages Monocrystalline structures:

8

to

Cost / Watt: Disadvantage The higher cost from production typically makes this less appealing to the general public. The advantage to black monocrystalline structures can be the shortened buyback cycle due to the higher efficiency.

Efficiency: Advantage Less efficient photovoltaics like poly crystalline or thin film technology require larger surface areas to produce the same total watts as mono crystalline photovoltaics. This is beneficial in places where space is limited.

Life Span : Advantage (Long) Because monocrystalline is first generation technology it has a proven track record of stability and performance. The current average lifespan solar photovoltaics is around 25-30 years. The inverters however might not last that long, around 20 years is there average life expectancy.5

Companies structures: Light Transmitting: Both The opaque character can be used as an advantage for shading. Examples have been to used as car shading devices such as the one on the top of the Long Center parking garage.

Instillation Process and Operation & Maintenance (O&M): Advantage (Low) When properly installed and sealed arrays can last for 20 years + and require little maintenance except the cleaning of the exterior glass and inverter check. If set onto the roof of a building these panels are easy to access and change if needed. These first generation type crystalline

that

Produce

Monocrystalline

Local (within two hundred miles): 1. Sun Tunnel Systems 2109 Northland Drive, Austin, Texas USA Telephone: 512-323-6696 2. vQuad Energy PO Box 690073, Houston, Texas USA Telephone: (281) 259-0393 http://www.quadenergy.com/

World: 1. PV Crystalox Solar plc 5

Ecostream

UTSoA - Seminar in Sustainable Design

Photovoltaic Application for the Scoreboard

Figure 07: Black Monocrsytalline Cell

Figure 08: Blue Monocrystalline Cell

Figure 09: Polycrystalline Cell Colors

174 Milton Park, Abingdon, Oxfordshire UK Telephone: 44 0 1235 437160 http://www.crystalox.com

a cube form, also known as and ingot. Through a process of heating and cooling, homogeneous silicon crystals form with visible grain sizes in the ingots [Figure 04]. The boundaries of the grain constitute defects that adversely affect the efficiency of the solar cells, which is slightly lower than monocrystalline cells. The ingots are sawn into bars and then cut into wafers about .3mm thick. The wafers are cleaned and phosphorousdoped and an anti-reflective coating is applied.

And, finally the contacts are printed and edges etched. The are then are ready to be assembled into a panel.

With 25 years in solar technology development, PV Crystalox Solar is a leading manufacturer of multicrystalline silicon ingots and wafers, the key component in solar power systems. Its customers, the world’s leading solar cell producers, combine these wafers into solar modules to harness the clean, silent and renewable power from the sun.

PV Crystalox Solar is playing a central role in making solar cost competitive with conventional hydrocarbon power generation, and as such continues to seek to drive down the cost of production whilst increasing solar cell efficiency.

The gap between the cost of solar power production and utility energy is decreasing year on year. With a long history of production with high growth and profitability, PV Crystalox Solar is well placed to benefit greatly from the rapid growth in the solar energy market.6

Panels: Like monocrystalline, polycrystalline wafers are brittle a require reinforcing to protect them and reinforce them in a panel. The wafers are laminated between two rigid substrates, usually glass and metal, plastic or glass. The panels themselves come in various sizes and can be custom designed, depending on the manufacturer.

2.1.2 Polycrystalline Silicon 7

Manufacturing Process: In the fabrication process, the silicon base material in melted in a quartz crucible and cast into 6 7

Silicon Valley Toxics Coalition Stopping the Solar ...

Planning and Installing Photovoltaic Systems

Efficiency: Polycrystalline panel efficiencies range from 13 to 16 percent. Although the efficiency is lower than monocrystalline cells, the manufacturing process lends itself toward larger wafer sizes, up to 8 inch edge length, hence a more efficient

production process and higher overall module efficiency. The larger cells bring down the cost of the module production and of the cells themselves, since fewer cells are needed per module.

Color: The polycrystalline wafers are generally blue or silver gray. One can vary the color slightly with by changing the thickness of the anti-reflective coating. Currently, the additional colors available are green, gold, brown and violet. However, the cost of using custom colors options is a lower cell efficiency, as the cells will absorb a narrower spectrum of light.

Light Transmitting: The cells themselves are opaque. However, they can be laminated between two transparent surfaces and the cells themselves spaced apart within the module to allow light to pass between, such as the shade canopy over the plaza at Austin City Hall. [See image A-68].

Companies structures:

that

Produce

Polycrystalline

1. Solar Power Industries 440 Jonathon Willey Road, Belle Vernon, PA

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UTSoA - Seminar in Sustainable Design

Photovoltaic Application for the Scoreboard

Figure 10: Photovoltaic Thin Film

Figure 11: Production of Thin Film Technology

15012 Telephone: 724 379 6500 http://www.solarpowerindustries.com/

deposited in very thin, consecutive layers of atoms, molecules, or ions. Thin-film cells have many advantages over their “thick-film” counterparts. For example, they use much less material—the cell’s active area is usually only 1 to 10 micrometers thick, whereas thick films typically are 100 to 300 micrometers thick. Also, thin-film cells can usually be manufactured in a large-area process, which can be an automated, continuous production process. Finally, they can be deposited on flexible substrate materials.

2. Solar-Tec 33971-A Silver Lantern, Dana Point, CA 92629 Telephone: 949 248 9728 http://www.solar-tec.com/ 3. Suntech America 71 Stevenson Street, 10th Floor, San Francisco, CA 94105 Telephone: 415 882 9922 http://www.suntech-power.com/

For further information on photovoltaic structures and the types of solar cells mentioned above, please see Planning and Installing Photovoltaic Systems. It is an invaluable resource.

2.1.3 Thin Film Photovoltaics One scientific discovery of the computer semiconductor industry also has great potential in the photovoltaic (PV) industry: thin-film technology. The “thin film” term comes from the method used to deposit the film, not from the thinness of the film: thin-film cells are

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Manufacturing Process: Thin-Film Deposition Several different deposition techniques can be used, and all of them are potentially less expensive than the ingot-growth techniques required for crystalline silicon. We can broadly classify deposition techniques into physical vapor deposition, chemical vapor deposition, electrochemical deposition, or a combination.

Both polycrystalline and amorphous silicon can be deposited on various low-cost substrates (or “superstrates”) such as glass, stainless steel, or plastic in virtually any shape.

In addition, these deposition processes can be scaled up easily, which means that the same technique used to make a 2-inch x 2inch laboratory cell can be used to make a 2foot x 5-foot PV module—in a sense, it’s just

one huge PV cell. Thin films are unlike singlecrystal silicon cells, which must be individually interconnected into a module. In contrast, thinfilm devices can be made as a single unit—that is, monolithically—with layer upon layer being deposited sequentially on some substrate, including deposition of an antireflection coating and transparent conducting oxide.

Types (amorphous and polycrystalline):8, 9 Copper Indium Diselenide (CIS) Copper indium diselenide (CuInSe2 or “CIS”) has an extremely high absorptivity, which means that 99% of the light shining on CIS will be absorbed in the first micrometer of the material.

Cells made from CIS are usually heterojunction structures—structures in which the junction is formed between semiconductors having different bandgaps. The most common material for the top or window layer in CIS devices is cadmium sulfide (CdS), although zinc is sometimes added to improve transparency. Adding small amounts of gallium to the lower absorbing CIS layer boosts its bandgap from its normal 1.0 electron-volts (eV), which improves the voltage and therefore the efficiency of the device. This particular variation is commonly called a copper indium gallium diselenide or “CIGS” PV cell.

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Haskell, Burt Thin Film

UTSoA - Seminar in Sustainable Design

Photovoltaic Application for the Scoreboard

Figure 12: Manufacturing of Thin Film

Cadmium Telluride (CdTe) Cadmium telluride is another prominent polycrystalline thin-film material. With a nearly ideal bandgap of 1.44 eV, CdTe also has a very high absorptivity. Although CdTe is most often used in PV devices without being alloyed, it is easily alloyed with zinc, mercury, and a few other elements to vary its properties. Like CIS, films of CdTe can be manufactured using low-cost techniques.

Also like CIS, the best CdTe cells employ a heterojunction interface, with cadmium sulfide (CdS) acting as a thin window layer. Tin oxide is used as a transparent conducting oxide and antireflection coating. One problem with CdTe is that p-type CdTe films tend to be highly resistive electrically, which leads to large internal resistance losses. A solution is to allow the CdTe layer to be intrinsic (that is, neither p-type nor n-type, but natural), and add a layer of p-type zinc telluride (ZnTe) between the CdTe and the back electrical contact. Although the n-type CdS and the p-type ZnTe are separated, they still form an electrical field that extends right through the intrinsic CdTe. When it comes to making CdTe cells, a wide variety of methods are possible, including closed-space sublimation, electrodeposition, and chemical vapor deposition.

Copper indium gallium selenide (CIGS)

CIGS is one form of thin-film polycrystalline photovoltaic. It has potential for high efficiency for both glass and flexible PV modules. A flexible module format will make the modules suitable for many residential, commercial, and utility applications, as well as integration within building materials.

companies, such as HelioVolt, expect to also hit the $1/Watt target with CIGS technology.

Efficiency: CIGS-type thin film solar cells have demonstrated up to 20% efficiency in laboratory settings, demonstrating CIGS potential as a low-cost, high-efficiency PV option. The many start-up companies developing CIGS manufacturing processes have only managed to create cells with about 10% efficiency, but the cost/watt ratio already appears to be advantageous for largesurface applications.10

Substrates (rigid/flexible): Advantage Amorphous silicon can be deposited on nearly any stable substrate or “superstrate,� such as glass, stainless steel, or plastic, and in virtually any shape. These can be rigid or flexible.

Advantages and Disadvantages to Thin Film Technologies:

Cost/Watt: Advantage The current market leader in thin film photovoltaic, First Solar, has already achieved a $1/Watt manufacturing cost with a cadmium telluride panel, and plans to batter this ration as they increase their scale of production. Other 10

Thin Film

Color Options: both Amorphous silicon thin film panels range from dark gray to black in appearance.

Efficiency: (slight) Disadvantage Commercially-available thin film solar cells have reached between 9% and 10% efficiency. The U.S. Departement of Energy predicts that thin film cells will move incrementally toward 15% efficiency. [http://www1.eere.energy.gov/solar/ thin_films.html] Lifespan and Maintenance requirements: First Solar offers a 10-year performance guarantee at 90% of the minimal rated power output, and a 25-year performance guarantee at 80% of the minimal rated power output.

Companies that Produce Thin Film PV:

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UTSoA - Seminar in Sustainable Design

Photovoltaic Application for the Scoreboard

Figure 13: Energy Production for an Organic Dye Sensitized Solar Cell

Polycrystalline 1. First Solar Headquarters: 350 West Washington Street Suite 600 Tempe, Arizona 85281 USA Tel: 602 414 9300 2. Manufacturing: First Solar, Inc. 28101 Cedar Park Blvd Perrysburg, Ohio 43551 USA Tel: 419 662 8500 Amorphous Silicon 3. HelioVolt Corporation 8201 E. Riverside Dr. Suite 600 Austin, Texas 78744-1604 Telephone: 512-767-6000

2.1.4 Organic Solar Cells Generic Differences of third generation solar cells: Researchers agree that the third generation of solar technologies provides the most opportunity for higher efficiencies with lower costs compared to the first and second generation technologies.

This third generation covers organic and polymer solar cells. They are constructed from thin films (typically 100mn thick) of organic semiconductors

and small molecule compounds.11 Within this category of photovoltaics there are numerous types of cells such as dye-sensitized, Nanocrystal, Hybrid, Tandem, Photoelectrochemical, and others. Among this group, dye-sensitized solar cells prove to be the only applicable building solution today. This technology is still in its infancy and each day new types of organic solar cells are being created while others are being perfected.

“Organic solar cells work differently from conventional inorganic semiconductor solar cells.

Light absorbed by an inorganic semiconductor produces free charge carriers – electrons and holes – that are transported separately through the semiconductor material. In an organic solar cell, however, light absorption produces excitons, electron-hole pairs that are bound together and hence not free to move separately. To generate free charge carriers, the excitons must be dissociated. This can happen in the presence of high electric fields, at a defect site in the material, or usually, at the interface between two materials that have a sufficient mismatch in their energy levels. Thus, an organic solar cell can be made with the following layered structure: positive electrode/electron donor/electron acceptor/ negative electrode. An exciton created in either the electron donor or electron acceptor layer can diffuse to the interface between the two, leading 3-

12

Polymer Solar Cells

to electron transfer from the donor material to the acceptor, or hole transfer from the acceptor to the donor. The negatively charged electron and the positively charged hole is then transported to the appropriate electrode. 12”

Dye-Sensitized Solar Cells Also known as DSSC, dye-sensitized solar cells are the most applicable solution out of all the organic solar cells due to its efficient manufacturing process, module flexibility, light transmittance, and available aesthetics. The dyes within the solar cells produce artificial photosynthesis by using dyes analogous to chlorophyll in plants.

The production of energy through artificial photosynthesis is a two step process unlike convention photovoltaics. The cell consists of a “layer of nano-particulate titania (Titanium Dioxide) formed on a transparent electrically conducting substrate and photosensitized by a monolayer of dye. An electrolyte, based on an Iodide - Tri-iodide redox system is placed between the layer of photosensitized titania and a second electrically conducting catalytic substrate. The DSSC is considered a photoelectrochemical cell: charge separation occurs on interface between a wide bandgap semiconductor (e.g.

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Ho, Mae-Wan

UTSoA - Seminar in Sustainable Design

Photovoltaic Application for the Scoreboard

Figure 14: DSSC Array

titanium dioxide) and an electrolyte. It is also a nanoparticulate porous film, not a dense film such as amorphous silicon, but a nanoparticulate cell also known as a “light sponge�. 13�

Manufacturing Process of DSSC The manufacture of organic cells is the most sustainable production of all solar cells to date.

The machinery used to create this technology is standard machinery available on the market.

Skilled labors are not required because most of the production can be fully automated. Some fabrication techniques even use electronic printing. This technology has the capacity to be produces cheaply in high volumes making it an economic alterative. The embodied energy of the manufacturing process is low and the production of the cells is environmentally friendly where most parts can be recycled.14

dye is changed, the cell must be altered to counteract corrosion, leakage, and maintain efficiencies. Higher producing dyes are being to enter the market such as K-19 that will create 6% efficiency, indoline dye produces 6.51%, N3 dye produces 7.89%, and N719 dye was 8.26%.

Other dye compounds that have the ability to compete with crystalline photovoltaics have not been released for consumer use. There is still vast amounts of research required but thus far the dye code named Z-910 produces about 10.2% efficiency, a pretreated cell with a hydrochloric acid solution grants 10.5%, and ruthenium based black dye can exceed 19.6% efficiency. 15, 16

Efficiency: Daily advances in energy efficiency of DSSC are creating a wide range of available efficiency numbers. A standard DSSC found on the market will currently reach roughly 5-6% efficiency. The efficiency of the cell and the lifespan directly relates to the dye being used internals. As the

Color: Any color found in nature or in our visible color spectrum can be made. These wide ranges of colors are made from simple abstraction of compounds found in nature. Due to the principal that light embodies all colors, using particular materials that reflect specific light waves will emit certain colors. For example, a green color will come from a green compound that absorbs all the colors of light except for the green wavelength, thus appearing to our eyes to be green. The green dye most commonly used is a synthetic chlorophyll derived from the light-harvesting

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15 16

How It Works How It Works

Ho, Mae-Wan High Efficiency of Dye-Sensitized Soar Cells...

pigments that plants use for photosynthesis.

Other colors come from minerals such as titanium dioxide which is plentiful, renewable, non-toxic, and is used in products such as toothpaste and paints.17

Malleability: DSSC can be applied to ridged substrates as well as flexible thin-film modules. The flexible modules require the addition of light harvesting organic plastic polymers within the cell. This technology can be applied to a variety of applications and can be made into sheets or coatings. Both application types of cells are lightweight, disposable, and customizable on the molecular level. 18

Advantages and Disadvantages to DyeSensitized solar cells: Cost / Watt: Advantage DSSC are roughly 1/10th the cost of silicon based photovoltaics which makes up for the cells low efficiency. With an average module efficiency of 5% and with 1700 kWh/m2-yr average yearly insolation the payback period is 4 months. [5] With government subsidies and incentives a typical consumer will pay roughly $3,000 17 18

Organic Solar Cell Breakthrough Raffaelle, Ryne

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UTSoA - Seminar in Sustainable Design

Photovoltaic Application for the Scoreboard

Figure 16: Multi Colored Dye Cell

Figure 15: Dye Sensitized Patterned Solar Cell

with a five year pay back. This is compared to silicon technology which would require the same average consumer roughly $12,000 and a payback period of about twelve years. Concrete and standard figures are not easily found due to the fact that this technology is still mainly in the libratory stages.19, 20 Efficiency: Disadvantage Currently the DSSC have lower efficiencies than silicon based solar panels. There is much potential for higher efficiencies however they will not be in production for a while. The most valuable aspect of using DSSC is that they produce energy in any quality of light due to the cell’s high internal surface area of titania known as a “light sponge”.

DSSC has much less sensitivity to the angle of incidence making them just as efficient when exposed to refracted or reflected light be used in cloudy climates, in shade, or even indoors. In low light conditions a 10x10cm cell is able to run a typical fan. Applications are endless and range from outdoor tents to cell phone holders. 2122 Color: Advantage Even though any color can be produced and made into a DSSC the highest energy efficient colors are ochre, blue, and green. Ideally all colors will be brought up to high standards of 19 20 21 22

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Organic Solar Cell Breakthrough Ho, Mae-Wan Organic Solar Cell Breakthrough Thin-film Technologies- Dye Solar Cell

Figure 17: Available Dye Colors

efficiency and will allow for such creations of stained glass windows.

Light Transmitting: Advantage Containing a liquid, the DSSC are able to have full to little light transmittance. There are a wide range of colored dyes and the darker the dye the less light is allowed to pass through. The cells do not have the capacity to be completely opaque, but this ability makes for a prime opportunity to integration into standard windows or in the creation of tinted windows.

Life Span: Disadvantage The weakness of this product is its stability and longevity. The organic molecules chemically decompose (a natural process) over a short period of time. UV rays degrade the cells and create distortion, lost of layer adhesion, and layers diffusing to each other can also occur over time. Further module design and the creation of stable molecules are needed. 23 Proposed energy efficient DSSC have as many negative aspects as they have positive. The advanced dyes are toxic, volatile, and some are noted to be carcinogenetic. Another problem is that particular dyes require expensive hermetic sealing of each cell. The use of electrolyte 23

Ho, Mae-Wan

gel in place of the dye improves longevity by reduces leakage. The gel also helps the cell resists freezing and expansion due to extreme temperatures and maintains a constant 6% efficiency. 24 Operation and Maintenance (O&M): Both Being able to absorb light in all conditions makes this solar cell the optimal solution for high latitudes. In all locations and conditions DSSC require similar care and maintenance as silicon based photovoltaic cells.

A very positive aspect of using dyes is that they can be easily extracted and injected. As the molecules break down, more can be easily added into the cell. This also allows for the cells to be “updated” by injecting a more energy efficient dye when found. This process will reduce both environmental and financial costs.

The downside to dye injection and extraction is the fact that some of the dyes are highly toxic such as ruthenium. They will not be handled by the consumer making it an expensive process that may not be able to done on site. 25, 26 Companies that Produce DSSC structures: USA 1. Konarka Technologies, Inc. 116 John Street Suite 12, 3rd Floor 24 25 26

Konno, Akinori and G. R. Asoka Kumara Ho, Mae-Wan Konno, Akinori and G. R. Asoka Kumara

UTSoA - Seminar in Sustainable Design

Photovoltaic Application for the Scoreboard

Figure 18: Green Flexible Organic Cell

Lowell, Masseuses USA Telephone: 1-978-569-1400 http://www.konarka.com/ World 1. DyeSol 3 Dominion Place Queanbeyan, NSW Telephone: 61 (0)2 6299 1592 http://www.dyesol.com 2. G24 Innovations Wentloog Environmental Centre Cardiff, United Kingdom Telephone: 44 (0) 29 2083 7340 http://www.g24i.com

Wentloog,

Other Types of Organic Cells Hybrid Solar Cells: These are just one type of organic solar cell.

They are the best combination between organic solar cells and inorganic semiconductors. The photoactive nanomaterials are introduces into polymer-based, thin-film photovoltaic devices.

In these cells the inorganic-semiconductor nanomaterials get dispersed in an organicpolymer matrix. The result of this mixture is a lightweight, efficient, flexible, and potentially inexpensive energy cell. This technology, along with polymer-based solar cells, is still very new and its efficiency with an average of 1.6%

efficiency is nowhere close to competing with other solar cells on the market. Researchers believe that there is great potential for 10% efficiency, but that technology is not been produced yet. 27 Tadem Solar Cells These have the most potential to create the most energy out off all the photovoltaics created thus far. They are manufactured by stacking several micro thin layers of p-n junction tuned into specific frequencies of the spectrum. The layers capture higher frequencies on the top and the lower frequency light traveling through them to the lower layers. Once this method has been perfected other materials could be used to make up the layers. This method is similar to the Shockley-Queisser analysis. In an ideal condition experiment a two-layered cell can reach 42%, a three layer cell reaches 49% and a theoretical infinity-layer cell could reach 68% maximum efficiency. These efficiency rates are staggering however, the efficiency drops off very quickly under low light levels. The Tandem cells will need to track the sun in order to maintain efficiency. As a result, no large scale commercial cell system has been deployed. 28

Nanocrystal Solar Cells 27 28

Raffaelle, Ryne Polymer Solar Cells

Nanocrystal solar cells rely on quantum dot fabrication through colloidal synthesis. Basically, this is the coating of nanocrystals on a silicon substrate. A thin film of nanocrystals is obtained by a process known as spin-coating and by roatating a flat substrate containing a small drop of quantum solution, the solution evenly and uniformly spreads across the substrate.

This technology is based around dye-sensitised colloidal TiO2 films. A single nanocrystal channel is between electrodes, each separated by ~1 execution diffusion length, was proved to increase efficiency. This technology is in its infancy, but research projects an efficiency of 65% efficiency once perfected. Some materials being currently tested have a high toxicity and are considered to negate the sustainability factor of these cells. A major stumbling block to the widespread production of this solar cell is the intensive manufacture process that has to take place under precisely controlled conditions, such as high vacuum and temperatures of up to 1,400 degrees Celsius with the need for immense levels of precision. 29

2.2 Tracking Systems Employing the use of pneumatic structures to mount the photovoltaics is one way of increasing 29

Polymer Solar Cells

15

UTSoA - Seminar in Sustainable Design

Photovoltaic Application for the Scoreboard

Figure 19: Single Axis Tracking System

Figure 20: Dual Axis Tracking System

the efficiency of the array and creating a more dynamic design that could potentially increase the visibility of the PV array. Pneumatic systems often serve a dual function. On a building façade, for example, PV shade louvers can track to follow the sun and/or change the amount of light allowed to penetrate the building.

PV tracking arrays, for example, move the PV surface to follow the sun. The increase in efficiency is quite significant: a 50 percent radiation gain in the summer and 300 percent gain in the winter, compared to a stationary horizontal surface. There are two types of tracking arrays: single-axis and dual-axis. The dual-axis always maintain the most optimal alignment to the sun.

However, because a dual-axis system is more mechanically complex, single-axis is usually preferred. The system can either track the sun’s annual path or daily path. There is about a 10 percent difference in energy yields between the

Figure 21: Solar Radiation of a Horizontal Verses a Tracking System

not outweigh the added cost when compared to a simple uniform PV array. Most of the PV tracing arrays are not building-integrated, but are mounted to the ground in an area where space is not a limiting factor, such as solar farms. The structures also require a mounting system that can withstand high wind loads. The systems generally use either an electric motor or thermohydraulic-control system. Another disadvantage is that if the tracking system fails, the PV array may be stuck in an poor position that could severely reduce the panel’s energy yield.

single and dual-axis tracking systems.

The tracking motor can be controlled with astronomically, they calculate the position of the sun and move the array accordingly, or with a light-sensor control, where they point the arrays, at the brightest point in the sky. The advantage of the sensor-controlled system is that it can find a more optimal yield position on a cloudy day. [figure 21]

Some of the disadvantages to tracking systems are that they are more complex to building, maintain, and therefore more expensive. And where area is limited, a tracking system may not be ideal, as the PV panels must be adequately spaced apart to allow for the movement to the arrays and to avoid shading each other as they move. This may mean using less PVs. The added efficiency of a tracking array may

Another way pneumatic PV array may be used is to create a dual-functioning system. For example, series of PV louvers could be positioned during the day for optimal energy yields. Then, when the PVs are not generating any energy, the louvers could rotate 180 degrees to expose the back of the PV module, when could be covered with an advertising image or perhaps a white screen that images could be projected upon. So, during the

16

day, the back of the Scoreboard could function as an energy plant, and at night it becomes a billboard or movie screen.

UTSoA - Seminar in Sustainable Design

3 Austin, Texas

Photovoltaic Application for the Scoreboard

The University of Texas’ main campus is located in the heart of Austin, Texas. Austin is the capitol of Texas and has roughly 1.6 million people making it the 36th largest city in the nation. The last two US censuses showed the city is doubling its population roughly every ten years, making it the second fastest growing city in the United States. The city is flanked by the Colorado River and contains many outdoor activities such as public parks, hiking and biking trails, natural springs, three man made lakes, and much more.

Austin is home to Fortune 500 companies such as Dell and Whole Foods Market. There is plenty of industry in the surrounding area including enough high technology corporations to earn the nick name of “Silicon Hills”. As a result Austin, Texas was rated Second in the “Best Big Cities to Live” by Money Magazine, ranked the 5th safest city in the US, voted America’s #1 College Town by the Travel Channel, as well as the “Greenest City in America” by MSN. 30

3.1 Local Condition “Austin, Texas is poised to set an example for the rest of the country, having successfully managed to shift its fiscal and social focus 30

Austin, Texas.

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UTSoA - Seminar in Sustainable Design

Photovoltaic Application for the Scoreboard

Figure 25: Average Temperatures for Austin, TX

Figure 22: Amount of solar radiation throughout the world

Figure 23: Potential renewable energy (quads)

Figure 24: Possible sunshine in Austin, TX

Figure 26: Power degradation with temp. increase

towards conservation and alternative energy.

31 ” The city is actively searching for ways to conserve energy and help citizens get financial assistance for using and applying these systems to their homes and businesses.

reach 100 degrees Fahrenheit and this area of the country as has mild winters with clear skies and little humidity with an average of 50 degrees Fahrenheit. [Figure 25]

3.1.2 Solar Support

The local incentives and push toward public education of sustainable options leads Austinites to embrace the movement. The Lone Star Chapter of the Sierra Club, based in Austin, counted almost 100 bills on solar and other renewable in the 2007 Texas legislative session.

The combination of the local climate and support the local gives toward conservation makes Austin the ideal location for photovoltaic instillations.

The city of Austin and neighboring San Antonio are working “together to capture good-paying clean technology jobs that will make Central Texas — everything between the corridor that is Austin and San Antonio — a national leader in solar energy. 32 ”

3.1.1 Climate Austin is situated south of the central portion of the states and is located in the humid subtropical climate zone of the US. This zone is characterized by hot summers of an average of 90 degrees Fahrenheit with mostly clear to partly cloudy skies. Highs in the summer can often 31 32

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How Green is Austin?

Dawson, Bill

Having little cloud cover throughout the year makes it one of the best for solar production of energy. As seen in figure 22, this portion of the United States receives roughly 1700- 1900 kWh/ m2 of solar irradiance. Texas is also the leader among the central US states fro the potential production of energy from biomass, wind, as well as solar. With these available natural resources, Texas can greatly decrease its dependence on oil and coal.

Austin is a prime location for the use of photovoltaics due to the large amounts of sunlight the area receives. There is little cloud cover and rainy days which allow the panels to work at peak efficiently throughout the year. The only aspect that would hinder their performance is the intense heat that the area receives during the summer. Excess heat above 90 degrees Fahrenheit decreases the efficiency of solar panels and the heat builds as the day goes on.

This incident is also true for excessive cold. The mild winters in Austin, Texas will keep the panels in the peek energy producing zone throughout most of the year.

Austin, Texas is considered one of the “Greenest” cities in the nation due to its focus on sustainability. “The success of Austin’s green energy program and other clean initiatives has helped focus national attention on our community and the quality of life which our city provides. This has helped promote Austin as a destination for both businesses and a progressive population.” said Mayor Will Wynn.33 The Austin City Council has established several resolutions to help move the city towards a carbon neutral state by 2010. It plans to cap CO2 emissions at 2,007 and reduce emissions to 2,005 by the year 2014 By doing this it hopes to achieve carbon-neutral generation. It seeks to attain 30% renewables by 2020 including 100 MW of solar and reach an additional 700 MW energy savings using demand side management and efficiency. As you can see, solar is a large portion of this plan. Through using solar technologies the city looks to reduce its carbon footprint, reduce pollution, as well as encourage local jobs and manufacturers.34 In further support of solar projects in and around the city, The Austin City Council has authorized the development of the largest solar power generating project in the U.S. located in Webberville, Texas. This 300 acre solar array 33 34

Partner Profile Austin Smart Energy

UTSoA - Seminar in Sustainable Design

Photovoltaic Application for the Scoreboard

Figure 28: Energy Prices (1980-2007 dollars per million Btu)

Figure 27: Austin’s resource and carbon reduction plan

will generate 30-megawatts annually which is enough to power 5,000 homes. “According to Austin Energy spokesperson Ed Clark, the new plant will help it meet its goal of receiving 30 percent of its energy from renewable sources by 2020.” 35 This array should be operational by December 2010.

Representatives in the Texas legislature are in full support of solar energy. This support can be seen in Senate Bill 545 that was past a few months ago. This bill seeks to develop solar energy technology in Texas. “By allowing for investment in solar technology, this measure is a significant step toward creating thousands of solar-related jobs in Texas and could lead to more manufacturing locating in the state.”36 They also approved one of the largest subsidy programs for solar-power in the US. The house recently approved $500 million dollars over five years for a rebate program that encourages solar installations. These rebates would encourage the use of solar for residential as well as business throughout the state. It is expected that roughly 250 to 500 MW be generated from these rebates and incentives which is equivalent to a single natural-gas power plant. This subsidy will also help to jumpstart the solar-manufacturing industry in Texas. ““These new bills would bring [Texas] into the forefront of states that have solar incentives and possibly help make them a leading producer of solar electricity,” said Glen 35 36

Calnan, Christopher Shapleigh, Eliot

Andersen, who tracks renewable energy for the National Conference of State Legislatures.” 37 Solar energy is being supported on a larger scale through Government interaction. They offer financial incentives, tax rebates, and project grants to decrease the current cost of the technology in order to increase the use of the technology. The US Department of Energy (DOE) recently passed the Emergency Economic Stabilization Act of 2008 (P.L. 110343). This Act extends and amends previous offers for businesses, utilities, and government originally introduced in the Energy Policy Act of 2005 (EPACT). These incentives also include tax credits for the production and facilities for sustainable energies including solar. In addition, $800 million dollars of Clean Renewable Energy Bonds (CREBs) were authorized to finance renewable facilities. A tax credit of 30% of the investment cost will be returned to the buyer after proper paperwork has been documented and completed. In order to receive the credit, the panels must be installed and in service by January 1, 2017. 38

of Austin City. The University is noted as being one the largest public research university with more than 3,500 research projects and funding exceeding $400 million dollars. Their drive for research and implementation has lead to roughly 400 patents which has generated more than $5 million dollars annually. With over 50,000 students and 16,500 employees, the university is a pressing entity within the state with the largest single campus enrolment in the country. The campus owns a total of 850 acres with the main campus compromising 350 acres. The campus is rich with thought and that can be seen in the main campus’ seven museums and seventeen libraries holding over eight million volumes. With the campuses large size also comes the nature as being the largest employer in the state of Texas producing an average of $6 million dollars in business activity. With these figures, it is no wonder that the University’s motto is, “What Starts Here Changes the World.” 39

3.2.1 Campus Resources

The University of Texas is located is at the heart of the state by being located in the center

“It takes a lot of natural resources to create a dynamic learning environment for [this many large numbers of] faculty and staff, and countless visitors. In FY 2007, utility costs for The University of Texas at Austin, including the main campus, downtown office space and Pickle Research Campus were close to $54

37 38

39

3.2 The University of Texas

Gold, Russell U.S Department of Energy

At a Glance

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UTSoA - Seminar in Sustainable Design

Photovoltaic Application for the Scoreboard

Figure 29: The University of Texas campus

million for natural gas, electricity, and water.” 40 In efforts to reduce energy costs and conserve resources the university initiated the UTake Charge program in 2007. This program also seeks to increase awareness of sustainable practices through everyday activities. Through replacing old lighting fixtures with efficient ones, replacing high water consuming toilets with low flow toilets, and installing fail safe steam traps to reduce the loss of steam through faulty openings will save $2.8 million dollars per year and 35 million pounds of carbon. In 2008, the University established a Campus Sustainability Policy. This policy establishes the scope, its definition, and its base implementation principles for creating a sustainable change within the university. See below for further information. 41 Campus Sustainability Policy Section I. General Policy Guidelines A. Policy Statement The University of Texas at Austin seeks to create a disciplined culture of excellence that generates intellectual excitement, transforms lives, and develops leaders. The Commission of 125 defines this culture as “excellence in all University endeavors, characterized by strong leadership and an engaged intellectual community, combined with individual and institutional accountability.” This includes excellence in advancing environmental stewardship and sustainability on our campus, in our academic and research programs, and in our public service and outreach activities. University 40 41

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Welcome to UTake Charge Campus Sustainability Policy

policies, practices and curricula should, when possible, embody approaches that reduce life cycle costs, restore or maintain the functioning of natural systems, and enhance human well-being. Our decisions and actions will be guided by the University’s mission statement, reflective of the University’s resources, and informed by the Commission of 125 and the Campus Master Plan.

B. Scope This policy applies to the main Campus, the J. J. Pickle Research Campus (PRC), and other sites as appropriate.

C. Definition Sustainability refers to societal efforts that meet the needs of present users without compromising the ability of future generations to meet their own needs.

Sustainability presumes that the planet’s resources are finite, and should be used conservatively, wisely, and equitably.

Decisions and investments aimed to promote sustainability will simultaneously advance economic vitality, ecological integrity, and social welfare.

D. Implementation Principles Academics: The University will strive for excellence in sustainability education and research by integrating sustainability concepts into curricula; supporting interdisciplinary scholarship, research and faculty hires; increasing faculty and student awareness of sustainability issues; and enhancing sustainability educational offerings. The University aims to produce scholars who are literate in sustainability, research that illuminates and advances sustainability, and graduates who will carry the mission of sustainability into the state, the nation and the world.

1.

Operations: The University will comply with all relevant environmental laws and regulations and aspire to go

beyond compliance by integrating values of sustainability, stewardship, and resource conservation into activities and services; make decisions, including staff hires, to improve the long-term quality and regenerative capacity of the environmental, social and economic systems that support the University’s activities and needs; engage in pollution prevention activities and develop and promote practices that maximize beneficial effects and minimize harmful effects of operations, research and activities on the surrounding environment; assess environmental impacts associated with activities; and develop and track measures of progress. The University’s goal is to maximize the efficiencies of its operations and services while minimizing its wastes and footprint.

2.

Campus Planning: The University will evaluate the impact of its construction projects; incorporate green building and design methods; and consider the needs of future generations of the University community, including its greater Austin setting, in campus planning, with the goal of minimizing the environmental footprint of the campus.

3.

Administration: The University will have sustainability goals that inform administrative policies and procedures in the areas of planning, decision-making, assessment, reporting, and alignment. These policies and procedures shall rely on scientific and technical analysis and support efforts to develop objectives and targets for operations, indicators, and measures to assure accountability, and reports on progress, with the overall goal of integrating knowledge of sustainability with actions to promote it.

4.

Outreach: The University will share with outside communities the knowledge generated from

UTSoA - Seminar in Sustainable Design

Photovoltaic Application for the Scoreboard

sustainability research, education, and practice; help promote environmental awareness and natural resource conservation; interact with the global community through on and off-campus activities; and pursue efforts, including providing incentives, to engage outside communities in developing research and education programs that respond to their interests and needs for sustainable well-being, with the goal of promoting a global culture of sustainability.

5.

Implementation: The University will establish near and longer term procedures and mechanisms, including an oversight structure, to review the status of each element of this policy and to ensure its implementation, with the goal of integrating informed and evolving practices for sustainability with the University’s mission of creating a disciplined culture of excellence.� 42

Within the University are many organizations, groups, and programs that are dedicated towards reducing consumption and taking steps towards preserving the environment. Most sustainable projects and organizations on the campus are student run. Some of these projects and organizations currently on campus are: Trash to Treasure, Students For Sustainability, Recycling, Sustainability Food Committee, Gardening Committee, Dorm EcoReps, Green Living Committee, Green Horns, Litter Reduction, Orange Bike Project, Climate Action, Engineers for a Sustainable Worlds, Earth Week 2009, and many others. The influence from these groups and projects can be seen around campus. 43 42 43

Campus Sustainability Policy.

Ut Campus Environmnetal Center

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UTSoA - Seminar in Sustainable Design

4 Building Integration

Photovoltaic Application for the Scoreboard

Photovoltaic applications to buildings began in the 1970’s, but construction products that incorporated photovoltaics into the building envelope did not begin until the 1990’s. As the years progressed, photovoltaic application became an effective technology for commercial, industrial, institutional, and residential application.

Photovoltaic arrays that are incorporated into the original design and function of the building are called Building-integrated photovoltaic (BIPV). 44 BIPV are considered multi-functioning building materials because they produce energy while completing the building envelope and protecting from the elements. BIPV are an integral part of the building façade, roof, or shading system.

Typical applications of BIPV come in the form of curtain walls, spandrel panels, glazing, tiles, shingles, skylights, and transparent windows.

PVs are limited by solar orientation, tilt, and existing shading and therefore cannot be applied evenly to all buildings. Each site and application must be examined extensively in order to achieve the optimal energy efficiency. 45 Beyond the aspect of BIPV being functional they also create an aesthetic element to the building through the addition of texture, color, and form.

Photovoltaics can be applied in a variety of shapes, sizes, and directions. These wide range of forms and uses make BIPV an essential part of the next generation of buildings.

44 45

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Eiffert, Patrina and Gregory Kiss Eiffert, Patrina and Gregory Kiss

UTSoA - Seminar in Sustainable Design

4.1 The Longhorns The University offers a wide range of athletic programs; both varsity and intramural programs.

In 2002, it was selected as “America’s Best Sports College” by Sports Illustrated. It also was noted as the number one “Collegiate Licensing Company Client” from 2005 to 2007 due to the amount of trademark royalties it has received from fan merchandise. Their official mascot and logo is Bevo the longhorn steer, and their colors are burnt orange and white.46 The Texas Longhorns compete in the Big 12 Conference and has won over 47 national championships, 39 of those are NCAA national championships. “In the Big 12 Conference sports, Texas has claimed more titles in men’s and women’s sports than any other school since the league began operating in 1996. In football, Texas has won four national championships and ranks second in NCAA all-time victories. Current and former University of Texas at Austin athletes have won 88 Olympic medals, including 19 in Athens in 2004.” 47Athletics is a large portion of the university which has generated much attention and fame throughout the years.

Despite the many outstanding athletics program on the Texas campus, the football programs stand out among the rest. The Longhorn football 46 47

Texas Longhorns At a Glance

Photovoltaic Application for the Scoreboard

Figure 30: Longhorn sports ranked as #1

Figure 31: Popularity of Longhorn football with all ages

team ranks as having the second most winning program in college football history with 831 wins (as of November 27, 2008). Darrell K. Royal- Texas Memorial Stadium is the home to the Texas football and is constantly evolving in reaction to the growing demand and attention gained by the successful football seasons. As of the 2008 season, the capacity of the stadium was 94,133 with an additional 2,000 club seats and 44 suites. 48

immediately visible to the university community, Austin, and the football-viewing public.

4.2 Scoreboard

The scoreboard is the nation’s largest highdefinition video display and second largest in the world. The $8-million Prostar Video Board was donated by DAKtronics. The scoreboard offers a multitude of viewing scenarios for the fans at the stadium, including live and recorded video, and single or multiple video images. And, there is an ongoing $150-million renovation project of the athletics buildings including the stadium, the Carpenter-Winkel Centennial Room and the interior of the Moncrief-Neuhuas Athletic Center.

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The scoreboard at University of Texas at Austin’s Darrell K. Royal Stadium provides ideal opportunity to promote the University as an institution at the forefront of sustainable technology. The University has a chance to set the stage for how people and institutions can tackle the volatile energy market and the climate crisis. The scoreboard is situated in a highly visible location for the University and for the city of Austin itself. The scoreboard faces only 5 degree off of south and is not shaded by any surrounding buildings, making it ideal for a photovoltaic installation. The scoreboard also has an unimpeded view of the state capitol and I-35 and can be seen from aerial views of the stadium during football games. A PV installation on the back of the scoreboard would be

The UT scoreboard consists of 36 LED panels that are attached to rigid steel frame sitting. The frame itself is 134 feet wide, 52 feet tall, and 7’ feet deep. It has a viewing box at the top which adds about 17 more feet to the score board and sits 35’ above the ground on six large columns.

The frame itself consists of 8” x 8” steel tubes running horizontally every 9’ - 5” which are attached to 6 steel I-beams that rest on the columns. The depth of the frame provides space for catwalks for maintenance access and house the AC units, chilled water piping, power supply, and other.

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49

Austin American-Statesman

With the exception of an access stair that provides access to the back of the scoreboard from the roof of the Moncreif-Neuhaus Athletic Darrell K Royal-Texas Memorial Stadium

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UTSoA - Seminar in Sustainable Design

Photovoltaic Application for the Scoreboard

Center just south of the stadium, all the service elements for the screens are housed within the frame, leaving the back of the structure clear to attach the some cladding system on the exterior, such as photovoltaic panels. Additional structure could be attached to the 8� x 8� steel tubes running horizontally or the vertical I-beams themselves.

Figure 32: Construction drawing of the back of the scoreboard showing its structure

The existing structure is also substantial enough that it would not require any additional structural support to compensate for added dead load or wind load from a panel system covered the entire area of the back. Any additional structure needed would just be a frame to hold the panels themselves and fix them to the scoreboard. The frame construction will depend the size and weight of the photovoltaic panels and layout of the design.

4.2.1 Orientation

Figure 33: Exposed back of scoreboard

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Studying the campus, the site, and the dynamics of Austin our team has found that the ideal application of photovoltaics to become a sustainable icon is a direct application to the scoreboard. This location can be seen by drivers on interstate 35 as well as from the Capitol Building. The scoreboard is the focus of the Darrell K. Royal-Texas Memorial Stadium and will be shown on every game day from multiple angles on and off the field. This evident

UTSoA - Seminar in Sustainable Design

Photovoltaic Application for the Scoreboard

placement and designed use establishes the Universities’ stance on sustainability and makes that statement to the world.

The large size of the scoreboard and its orientation due south is perfect for a photovoltaic application. The back of the scoreboard receives a noteworthy portion of solar radiation each year.

Through a study of solar radiation throughout the year and the average photovoltaic energy production we were able to see roughly how much energy could be produced during the given time. The results of the study, as seen in figure 35, and shows that the largest energy producing months are in the fall semester which coincides with the height of football season.

Figure 34: Areal view of stadium under construction

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UTSoA - Seminar in Sustainable Design

2006 2006 2006 2006 2007 2007 2007 2007

September October November December January February March April

2007 2007 2007 2007 2007 2007 2007 2007 2008 2008 2008 2008 2008 2008 2008 2008 2008 2008 2008 2008 2009 2009

May June July August September October November December January February March April May June July August September October November December January February

igure

26

nerg

consumption and available energ

Photovoltaic Application for the Scoreboard

29635 36679 49535 51965 54645 58154 64121 66394 69211 74482 79121 89320 110541 117154 124105 126631 129425 131896 141001 143590 146391 159548 160909 169234 182595 202366 218935 226507 230277 239590 generation per month

29635 7044 12856 2430 2680 3509 5967 2273 2817 5271 4639 10199 21221 6613 6951 2526 2794 2471 9105 2589 2801 13157 1361 8325 13361 19771 16569 7572 3770 9313

The figure to the left sho s the possible energ generation per solar radiation over a four ear time period The first column of numbers is the total number of ilo att hours h used b the scoreboard The second column of numbers is the monthl usage in h The color coding sho s the lo medium and high months for energ generation These numbers sho that the height of the energ production is in September and ctober

UTSoA - Seminar in Sustainable Design

Photovoltaic Application for the Scoreboard

kW/day Month January February March April May June July August September October November December Year Avg. Solar Radiation (kWh/m2/day)

igure

Variables:

0 3.06 3.89 4.83 5.41 5.92 6.61 6.77 6.27 5.22 4.48 3.32 2.72

15 3.79 4.55 5.30 5.62 5.90 6.45 6.68 6.43 5.66 5.21 4.07 3.43

30 4.31 4.96 5.49 5.54 5.57 5.96 6.24 6.23 5.78 5.65 4.59 3.96

45 4.59 5.09 5.38 5.17 4.96 5.18 5.47 5.70 5.59 5.77 4.86 4.26

60 4.61 4.94 4.98 4.53 4.12 4.18 4.47 4.87 5.10 5.55 4.85 4.33

75 4.38 4.52 4.32 3.68 3.12 3.03 3.28 3.81 4.33 5.03 4.56 4.14

90 3.90 3.85 3.45 2.68 2.08 1.93 2.11 2.61 3.36 4.22 4.02 3.73

4.88

5.26

5.36

5.17

4.71

4.02

3.16

Efficiency Rate of Solar Panels

1.00

Surface Area in m2

1.00

Knowns kWh/m2/day

PV Watts

Convert Sq. Ft. to Sq. Meters Square Feet

9.00

Square Meters

1

Convert FT. to M. Feet

1

Meters

0.3048

Solar radiation per surface orientation

Energy Output ( PV Watts) 8.00 0 degrees 7.00

15 degrees

30 degrees

6.00

kWh/m2/day

5.00

45 degrees

4.00 60 degrees 3.00

2.00

75 degrees

1.00 90 degrees

igure

0 15 30 45 60 75 90

igure

7

DECEMBER

NOVEMBER

OCTOBER

SEPTEMBER

AUGUST

JULY

JUNE

MAY

APRIL

MARCH

FEBRUARY

JANUARY

0.00

These series of charts and graphs are a comparison stud of the average po er output e used a fi ed panels and a degree a imuth for a datum for energ output Then using P atts e ad usted the tilt of the arra to determine the possible output These graphs sho the percent difference bet een alternating orientations using the earl solar radiation average The greatest finding through these graphs is the fact of ho much more po er a degree tilt off hori on ill generate over a vertical surface As the degree tilt decreases so does the energ generation of the photovoltaic arra

4.2.2 Design Iteration

Solar radiation per surface orientation graph

4.88 5.26 5.36 5.17 4.71 4.02 3.16

0

15

4.88

5.26

30 5.36

45 5.17

60 4.71

75 4.02

98.15% 101.73% 111.60% 130.89% 166.29%

103.64% 113.71% 133.36% 169.43%

109.71% 128.67% 163.47%

117.28% 149.00%

127.04%

92.72% 91.01% 94.32% 103.48% 121.37% 154.19%

90 3.16

The si e structure and solar orientation due south is ideal for photovoltaic energ production ithin these aspects our group has formed t o design scenarios for the Universities consideration The first is a straightfor ard approach that ma imi es cost and efficienc The second design ma es a bold statement of sustainabilit and combines use ith the ad oining tent structure oth designs use different photovoltaic cells and have dramaticall different forms ven though these designs are e tremes of each other the both generate note orth energ production and provide a carbon offset for the entire campus

Po er output ratio per surface orientation

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UTSoA - Seminar in Sustainable Design

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Photovoltaic Application for the Scoreboard

UTSoA - Seminar in Sustainable Design

Photovoltaic Application for the Scoreboard

Figure 39: Concept sketch

5 The Solar Veil

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UTSoA - Seminar in Sustainable Design

Figure 40: Game day view of stadium with Solar veil design

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Photovoltaic Application for the Scoreboard

UTSoA - Seminar in Sustainable Design

Photovoltaic Application for the Scoreboard

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UTSoA - Seminar in Sustainable Design

Photovoltaic Application for the Scoreboard

Figure 41: Ground view of the solar veil

The first photovoltaic design iteration uses monocrystalline panels provided by SunPower.

The arrays are mounted vertically (90 degrees) to the back of the scoreboard and cover the entire area provided by the existing structure. By mounting the panels vertically we are able to fit the maximum number of panels possible within the area provided, while using the simplest method of construction to mount them to the existing structure. This design will require a minimal amount of extra material to mount the panels to the scoreboard.

The monocrystalline panels are slightly separated from one another when mounted on the rear of the scoreboard. Around and behind each panel will be a series of light emitting diodes (LED).

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Depending upon the particular LEDs chosen, the back of the scoreboard will create dramatic glow or distinct and solid color. A subtle glow during day games and dramatic radiance during night games create interest and life to the rigid form. A wide range of colors can be displayed on this application including a gradation of color that can match the symbolic nature of the Tower illuminating orange on special occasions.

5.1 Solar Monocrystalline panels by SunPower would be used to clad that back of the scoreboard.

Monocrystalline photovoltaic panels in general have the highest efficiency out of all the photovoltaics on the market currently. The

SunPower panels advertise an 18.7 percent energy efficiency, which is the highest producing panel commercially available. 416 SunPower’s number 305 panels, dimensioned at 61.39in x 41.18in each, would cover back of the entire scoreboard. Figure 46 shows that with the increasing energy costs, the flat cost payback for the panels along could be anywhere from 20 to 113 years. As the cost of energy increases, the shorter the payback cycle of the instillation. See SunPower specifications under appendix A-67 for the detailed panel information.

UTSoA - Seminar in Sustainable Design

Photovoltaic Application for the Scoreboard

Figure 42: Night view

Figure 43: Night game ground view

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Photovoltaic Application for the Scoreboard

5.2 Structure The current structure of the scoreboard has been over sized to ensure the longevity of the instillation. The attachment of these panels to the pre-existing structure would not alter the existing loads. The additional structure necessary to hold the pv panels will attach to 8” x 8” steel tubes that span horizontally across the existing structure. The PV panels would be mounted to 2” x 2” steel tubes running vertically and spaced the width of the panels. This frame would then be bolted directly to the existing structure and allow for thermal expansion and a slight give in the frame. Additional steel angles, for ease of construction, would be used to help fasten the frame to 8” x 8” tubes. The attachment is designed for ease of attachment or removal of an individual panel by one person from the safety of the interior catwalk.

This aspect will help reduce operation and maintenance costs. [Figure 44]

5.3. Figures:

Figure 44: Panel attachment

The Solar Cascade can fit 416 of SunPower’s 305 panel on the back of the scoreboard. We estimate that the upfront cost of this PV array ( at $8/Watt ) is about $1 million dollars, and will generate about 112,000 kWh per year. We also estimate that this installation will take about 46 years of payback, but will offset 3,266 tons of carbon within the first 50 years of its life. See Chart 47 for detailed figures.

5.4 Advantage/Disadvantage This option takes advantage of the highest efficiency panel available and requires the simplest construction and least amount of material to fix the panels to the back of the scoreboard. The disadvantage to this option is that it does not take advantage of the prominent location of the scoreboard. The scoreboard is highly visible object. It has uninhibited views from the state capitol and I-35 and even during aerial shots of the stadium during games.

Figure 45: panel detail

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# of panels 416

Photovoltaic Application for the Scoreboard

SOLAR VEIL PAYBACK ESTIMATE FOR ELECTRICITY COST PER KWH

SUNPOWER PANEL watts per panel 305

System Size (kW) Output / day kWhaverage

308.7

Output / year kWh

112684

Instulation cost ( $ / Watt )

$8.00

Upfront Installed Cost ( Dollars )

$1,015,040.00

Electricity Cost ($/kWh) $0.08 $0.09 $0.12 $0.16 $0.20 $0.24 $0.28 $0.32 $0.36 $0.40 $0.44

126.88

* energy output estimated using PVWatts Version 1 Calculator

Energy Generated / day $25 $28 $37 $49 $62 $74 $86 $99 $111 $123 $136

Cost Savings / Year $9,015 $10,367 $13,522 $18,030 $22,537 $27,044 $31,552 $36,059 $40,566 $45,074 $49,581

Payback Years 113 98 75 56 45 38 32 28 25 23 20

Figure 46: Chosen panel specifications and their payback estimate SOLAR VEIL CARBON OFFSET AND ENERGY BUYBACK ESTIMATE Cost / kWh Austin

Year

Energy cost +5% increase fuel cost

2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 Totals after 50 years

0.092 0.10 0.10 0.11 0.11 0.12 0.12 0.13 0.14 0.14 0.15 0.16 0.17 0.17 0.18 0.19 0.20 0.21 0.22 0.23 0.24 0.26 0.27 0.28 0.30 0.31 0.33 0.34 0.36 0.38 0.40 0.42 0.44 0.46 0.48 0.51 0.53 0.56 0.59 0.62 0.65 0.68 0.71 0.75 0.79 0.83 0.87 0.91 0.96 1.00

Array Degradation

Power Output kW/day

Power Output kW/Year

Energy Generated

100.00% 99.50% 99.00% 98.50% 98.00% 97.50% 97.00% 96.50% 96.00% 95.50% 95.00% 94.50% 94.00% 93.50% 93.00% 92.50% 92.00% 91.50% 91.00% 90.50% 90.00% 89.50% 89.00% 88.50% 88.00% 87.50% 87.00% 86.50% 86.00% 85.50% 85.00% 84.50% 84.00% 83.50% 83.00% 82.50% 82.00% 81.50% 81.00% 80.50% 80.00% 79.50% 79.00% 78.50% 78.00% 77.50% 77.00% 76.50% 76.00% 75.50%

309 307 306 304 303 301 299 298 296 295 293 292 290 289 287 286 284 282 281 279 278 276 275 273 272 270 269 267 266 264 262 261 259 258 256 255 253 252 250 249 247 245 244 242 241 239 238 236 235 233

112684 112121 111558 110994 110431 109867 109304 108740 108177 107614 107050 106487 105923 105360 104797 104233 103670 103106 102543 101979 101416 100853 100289 99726 99162 98599 98035 97472 96909 96345 95782 95218 94655 94091 93528 92965 92401 91838 91274 90711 90148 89584 89021 88457 87894 87330 86767 86204 85640 85077 4,944,029

$28 $30 $31 $32 $34 $35 $37 $39 $40 $42 $44 $46 $48 $50 $52 $55 $57 $60 $62 $65 $68 $71 $74 $77 $81 $84 $88 $92 $96 $100 $104 $109 $114 $119 $124 $129 $135 $141 $147 $153 $160 $167 $174 $182 $190 $198 $206 $215 $225 $234

4.9 megawatts Total Watts Created total cost savings

Savings / Year

$10,367 $10,831 $11,315 $11,821 $12,349 $12,900 $13,476 $14,077 $14,704 $15,359 $16,042 $16,756 $17,501 $18,278 $19,089 $19,936 $20,819 $21,742 $22,704 $23,708 $24,756 $25,849 $26,990 $28,181 $29,422 $30,718 $32,070 $33,479 $34,950 $36,484 $38,085 $39,754 $41,494 $43,310 $45,203 $47,177 $49,236 $51,382 $53,620 $55,954 $58,387 $60,923 $63,567 $66,323 $69,195 $72,189 $75,310 $78,562 $81,951 $85,482 $1,803,775 $1.8 million

Carbon Offset tons of C02 74 74 74 73 73 73 72 72 71 71 71 70 70 70 69 69 68 68 68 67 67 67 66 66 65 65 65 64 64 64 63 63 63 62 62 61 61 61 60 60 60 59 59 58 58 58 57 57 57 56 3,266 3,266 tons of carbon

Cost of carbon ($) Future cost of + 2% yearly Carbon/ton at increase $20.00(1.02) 0 0 12 12 12 13 13 13 14 14 14 14 15 15 15 16 16 16 16 17 17 17 18 18 19 19 19 20 20 20 21 21 22 22 23 23 24 24 24 25 25 26 26 27 28 28 29 29 30 30

0 0 884 897 911 924 938 952 966 980 994 1009 1023 1038 1053 1069 1084 1100 1116 1132 1148 1165 1181 1198 1215 1232 1250 1267 1285 1303 1322 1340 1359 1378 1397 1416 1436 1456 1476 1496 1516 1537 1558 1579 1600 1622 1644 1666 1688 1710

Buy Back Remaining (1,004,673) (993,842) (981,643) (968,924) (955,665) (941,840) (927,426) (912,398) (896,728) (880,390) (863,353) (845,589) (827,065) (807,749) (787,606) (766,602) (744,698) (721,857) (698,037) (673,197) (647,293) (620,279) (592,108) (562,729) (532,092) (500,142) (466,822) (432,075) (395,840) (358,052) (318,645) (277,552) (234,698) (190,011) (143,411) (94,817) (44,146) 8,692 63,788 121,238 181,141 243,601 308,726 376,627 447,423 521,234 598,187 678,414 762,053 849,245

$60,510 $60 thousand

4,900,000 watts or 2.2 million

Figure 47: Solar veil energy and carbon

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Photovoltaic Application for the Scoreboard

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Photovoltaic Application for the Scoreboard

Figure 48: Concept Sketch

6 The Solar Cascade

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Figure 49: Day game with views into the stadium

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Photovoltaic Application for the Scoreboard

UTSoA - Seminar in Sustainable Design

Photovoltaic Application for the Scoreboard

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Figure 50: Night view of stadium with partially illuminated board

Figure 51: Fully illuminated board with fireworks at the start of the game

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Photovoltaic Application for the Scoreboard

UTSoA - Seminar in Sustainable Design

Photovoltaic Application for the Scoreboard

Figure 53: Day game with LED advertisement logos

Figure 54: Night game with LED advertisement logos

Figure 52: LED lights for display

This design seeks to serve multiple purposes for the university. In addition to generating energy for the school and offsetting its carbon footprint, the swooping form is at a larger scale to match the image of the stadium and be particularly visible from I-35 and other viewing corridors around the UT campus. The in addition covering that back of the scoreboard, the structure reaches out over the Moncreif-Neuhaus Athletic Center, providing additional cover for the small practice field on its roof. This structure also has the potential to light up and night in the same vain as the main tower, and light up in response to the stadium crowd’s enthusiasm or when a touch down is scored, letting Austin know how the game is going [Figure 52]. And, as the structure will be

easily viewed from aerial shots during the game or from I-35, the panels could light up with an advertisement or a message to students [Figure 53 and 54].

6.1 Solar The swooping structure will be clad with HelioVolt’s thin film photovoltaic panels. HelioVolt is an up and coming Austin based PV manufacturer of a new type of thin film technology, CIGS (Copper, Indium, Gallium, Selenium). The efficiency of the panels is lower than monocrystalline or polycrystalline, but they have an innovative manufacturing process that significantly lowers

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# of panels 4666

Photovoltaic Application for the Scoreboard

HELIOVOLT PANEL watts per panel 68.7

System Size (kW) Output / day kWhaverage

1034.25

Output / year kWh

377501

Instulation cost ( $ / Watt )

$15.00

SOLAR CASCADE PAYBACK ESTIMATE PER ELECTRICITY COST PER KWH Electricity Cost ($/kWh) $0.08 $0.09 $0.12 $0.16 $0.20 $0.24 $0.28 $0.32 $0.36 $0.40 $0.44

320.5542

Upfront Installed Cost ( Dollars ) $4,808,313.00 * energy output estimated using PVWatts Version 1 Calculator

Energy Generated / day $83 $95 $124 $165 $207 $248 $290 $331 $372 $414 $455

Cost Savings / Year $30,200 $34,730 $45,300 $60,400 $75,500 $90,600 $105,700 $120,800 $135,900 $151,000 $166,100

Payback Years 26 22 17 13 10 9 7 6 6 5 5

Figure 56: Payback estimate per electricity cost

Figure 55: Chosen thin film panel

SOLAR CASCADE CARBON OFFSET AND ENERGY BUYBACK ESTIMATE Cost / kWh Austin

Year

Energy cost +5% increase fuel cost

2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 Totals after 30 years

0.092 0.10 0.10 0.11 0.11 0.12 0.12 0.13 0.14 0.14 0.15 0.16 0.17 0.17 0.18 0.19 0.20 0.21 0.22 0.23 0.24 0.26 0.27 0.28 0.30 0.31 0.33 0.34 0.36 0.38 0.40

Array Degradation

Power Output kW/day

Power Output kW/Year

Energy Generated

100.00% 99.50% 99.00% 98.50% 98.00% 97.50% 97.00% 96.50% 96.00% 95.50% 95.00% 94.50% 94.00% 93.50% 93.00% 92.50% 92.00% 91.50% 91.00% 90.50% 90.00% 89.50% 89.00% 88.50% 88.00% 87.50% 87.00% 86.50% 86.00% 85.50% 85.00%

1034 1029 1024 1019 1014 1008 1003 998 993 988 983 977 972 967 962 957 952 946 941 936 931 926 920 915 910 905 900 895 889 884 879

377501 375613 373726 371838 369951 368063 366176 364288 362401 360513 358626 356738 354851 352963 351076 349188 347301 345413 343526 341638 339751 337863 335976 334088 332201 330313 328426 326538 324651 322763 320876 10,824,841

$95 $99 $104 $108 $113 $118 $124 $129 $135 $141 $147 $154 $161 $168 $175 $183 $191 $200 $208 $218 $227 $237 $248 $259 $270 $282 $294 $307 $321 $335 $350

10.8 megawatts Total Watts Created

10,800,000 watts or 10.8 megawatts

total cost savings

2.2 million

Figure 57: Energy production per savings and carbon reduction

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Savings / Year

$34,730 $36,284 $37,907 $39,601 $41,370 $43,217 $45,145 $47,158 $49,260 $51,453 $53,743 $56,133 $58,628 $61,232 $63,950 $66,786 $69,747 $72,836 $76,060 $79,424 $82,934 $86,597 $90,419 $94,407 $98,567 $102,907 $107,435 $112,159 $117,086 $122,225 $127,586 $2,226,989 $2.2 million

Carbon Offset tons of C02 249 248 247 246 244 243 242 241 239 238 237 236 234 233 232 231 229 228 227 226 224 223 222 221 219 218 217 216 214 213 212 7,150 7,150 tons of carbon

Cost of carbon ($) + 2% yearly increase

Future cost of Carbon/ton at $20.00(1.02)

0 0 12 12 12 13 13 13 14 14 14 14 15 15 15 16 16 16 16 17 17 17 18 18 19 19 19 20 20 20 21

0 0 2962 3006 3051 3096 3142 3188 3235 3282 3330 3379 3428 3478 3529 3580 3632 3685 3738 3792 3846 3901 3957 4013 4071 4128 4187 4246 4306 4367 4428 $105,984 $105 thousand

Buy Back Remaining (740,206) (703,922) (663,052) (620,445) (576,024) (529,711) (481,424) (431,078) (378,583) (323,848) (266,774) (207,262) (145,205) (80,495) (13,016) 57,350 130,729 207,250 287,047 370,263 457,043 547,542 641,918 740,338 842,976 950,011 1,061,634 1,178,038 1,299,430 1,426,022 1,558,037

UTSoA - Seminar in Sustainable Design

Figure 58: Allianz arena illuminated for games

Photovoltaic Application for the Scoreboard

Figure 60: Reticulated free-span structure concept

Figure 61: Joint for reticulated free-span roof structure

Figure 59: Norman Foster + Partners’ Robert and Arlene Kogod Courtyard at the Smithsonian Institute

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Photovoltaic Application for the Scoreboard

Figure 62: Structural section for Solar Cascade

the cost and amount to material and energy used to produce the cells. LED lights could be sandwiched with the PV cells in the glass and light up to form the advertisement or message or become a light signal to the University and Austin during a game.

6.2 Structure The structure of this dynamic design takes advantage of a relatively new form of spatial structural grid. As opposed to a space frame, the structure using a single layer surface to support the geometry of the architecture. There is a special bolted connection that allows for complex geometric forms (see image of Novum joint). Even the most irregular surfaces can use this standard beam connector without requiring secondary steelwork. (see Novum Structures website). A number of projects have been completed using this structural system, such as Foster + Partner’s Kogod Courtyard at the Smithsonian American Art Museum and National Portrait Gallery (see figure ?).

6.3 Figures The Solar Cascade can accommodate 4666 of HelioVolt’s thinfilm panel. Although the efficiency of their panel is about half the efficiency of SunPower’s monocrystalline panel, the payback period is actually much lower. Because the PV

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area is three times as much and the orientation of those panels more optimal that the Solar Veil, this design generates more energy, and therefore a quicker payback period. We estimate that the upfront cost of this installation will be about $4.8 million (at $15/Watt). But, the system will take only 15 years to payback and after 30 years the system could offset 7,150 tons of carbon. See Chart 1,2,3 for more detailed figures.

6.4 Advantage/Disadvantage: The disadvantage to this design is a significant increase in the initial cost of the installation, as opposed to the Solar Veil. However, because of the large size and the orientation of the panels, this design would generate more energy and therefore more money for the school. The size, shape and additional uses for this structure will increase its visibility and interest for the school.

The curve shape also offers the opportunity to test the performance of the panels at different orientations and could offer other research and learning opportunities.

UTSoA - Seminar in Sustainable Design

Photovoltaic Application for the Scoreboard

Figure 63: Breakdown of photovoltaic angles

Figure 64: Insolation received on the variety of panels

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7 Call to action

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Photovoltaic Application for the Scoreboard

As a world class public research institution, and and one of the largest in the country with a first class athletics department to match, the University of Texas has the opportunity to plant the seeds to catalyze change within the local Austin community, the nationwide academic community and the nation as a whole. A photovoltaic installation of visual prominence that can be tied directly to such a source of pride for the school, our football team, and prove to the nation that sustainable technology can be successfully integrated into the existing social and technological framework. UT can make a difference by showing this successful integration of clean technology, education and fun. In this way, the University can play a role in shifting negative mind-set about the role of sustainable values in people’s daily lives and prove itself a leader in tackling climate crises and in create energy independence for the country.

As students ourselves, we would love to see the University of Texas takes a more visible role in tackling such critical issues.

UTSoA - Seminar in Sustainable Design

A.03.html

7.1 Sources/Special Thanks Dr Werner Lang, Associate Department of Architecture

Professor,

Amy M Crossette, Director of Public Affairs, Vice President for Public Affairs Dr Richard Klingner, LP Gilvin Centennial Professor in Civil Engineering, Department of Architectural and Environmental Engineering Andrew McCalla, CEO and President, Meridian Energy Systems Cody Kelso, Assistant Intercollegiate Athletics

Events

Photovoltaic Application for the Scoreboard

Manager,

Steve Kraal, UT Office for Campus Planning and Facilities Management Leslie Libby, Austin Energy Bert Haskell, Director of Product Development, Andrew Heliovolt

7.2 Work Cited / References At a Glance. The University of Texas at Austin.

June 19, 2008. http://www.utexas.edu/opa/pubs/ facts/athletics.php Austin American-Statesman. 2009. http://www. statesman.com/ Austin Energy the Go-Ahead For Major Solar Project. March 5, 2009. Austin Business Journal. http://austin.bizjournals.com/austin/ stories/2009/03/02/daily49.html Austin Smart Energy. Fact Sheet. 2009. http://www.austinsmartenergy.com/divison. php?page=learn_more&sub=fact_sheet Austin, TX’s Mayor Wynn and City Council Approve One of Nation’s Largest Solar Power Plants. ICLEI- Local Government for Sustainability. Accessed May 6, 2009. http:// www.icleiusa.org/news-events/austin-txsmayor-wynn-and-city-council-approve-one-ofnation2019s/ Dawson, Bill. Solar’s Time To Shine in Texas?

March 23, 2009. Texas Climate News. Accessed May 6, 2009. http://www.texasclimatenews.org/ Campus Sustainability Policy. The University of Texas at Austin Revised Handbook of Operating Procedures. Policy Number 1.A.3. April 22, 2008. http://www.utexas.edu/policies/hoppm/01.

www.huffingtonpost.com/2008/10/21/howgreen-is-austin_n_136578.html

Calnan, Christopher. City Council Goved Austin Energy the Go-Ahead For Major Solar Project. March 5, 2009. Austin Business Journal. http://austin.bizjournals.com/austin/ stories/2009/03/02/daily49.html

How It Works. DYESOL. Accessed May 6, 2009. http://www.dyesol.com/index. php?page=HowItWorks

Darrell K Royal-Texas Memorial Stadium.

Viewed on 05.07.2009. http://www.texassports. com/facilities/royal-memorial-stadium.html

Konno, Akinori and G. R. Asoka Kumara. Metal Free Organic Dye-Sensitized Solid-State Solar Cell. Faculty of Engineering, Shizuoka University.

Accessed May 6, 2009. http://www.electrochem. org/meetings/scheduler/abstracts/214/0262.pdf

Dawson, Bill. Solar’s Time To Shine in Texas?

March 23, 2009. Texas Climate News. Accessed May 6, 2009. http://www.texasclimatenews.org/ Dye Sensitized Solar Cells. March 19, 2006.

Nanomech in Photovoltaics. Accessed May 6, 2009. http://nanoparis.blogspot.com/2006/03/ dye-sensitized-solar-cells.html Eiffert, Patrina and Gregory Kiss. BuildingIntegrated Photovoltaic Desings for Commercial and Institutional Structures. A Sourcebook for Architects. 2000. National Renewable Energy Laboratory. Accessed May 7, 2009. www.nrel. gov/docs/fy00osti/25272.pdf Ecostream. 2006. http://www.ecostream.us/

G, John. Global Solar Photovoltaic Market Analysis and Forecasts to 2020. March 13, 2009.

Aarkstore Enterprise. Accessed May 6, 2009. http://www.prlog.org/10198293-global-solarphotovoltaic-market-analysis-and-forecasts-to2020.pdf Gold, Russell. Texas Moves to Foster Solar Power. April 23, 2009. The Wall Street Journal.

Accessed May 6, 2009. http://online.wsj.com/ article/SB124042738382344591.html Haskell, Burt. HelioVolt’s Director of Product Development.

Lecture and PowerPoint presentation given February 5, 2009 to the University of Texas at Austin.

High Efficiency of Dye-Sensitized Soar Cells Based on Metal-Free Indoline Dyes.

September 10, 2004. Journal of the American Chemical Society. American Chemical Society.

Accessed May 6, 2009. http://pubs.acs.org/doi/ abs/10.1021/ja0488277 Ho, Mae-Wan. Organic Solar Power. Report 18/01/06. Institute of Science in Society.

Accessed May 6, 2009. http://www.i-sis.org.uk/ OSP.php How Green is Austin? October 21, 2008.

Huffington Post. Accessed May 6, 2009. http://

Kropp, Robert. Solar Expected to Maintain its Status as the World’s Fastest-Growing Energy Technology. Sustainability Investment News.

March 3, 2009. Social Funds. Accessed May 6, 2009. http://www.socialfunds.com/news/article. cgi/2639.html Novum Structures. Acessed May 10, 2008. http://www.novumstructures.com/novum/ Organic Solar Cell Breakthrough. April 9, 2007.

Go Sun Solutions. Accessed May 6, 2009. http:// gosunsolutions.com/home/content/view/46/2/ Partner Profile. Green Power Partnership. U.S. Environmental Protection Agency. Accessed May 6, 2009. http://www.epa.gov/greenpower/ partners/partners/cityofaustintx.htm Photovoltaics: Solar Electricity and Solar Cells in Theory and Practice. The Solarserver. Forum for Solar Energy. May 7, 2009. http://www. solarserver.de/wissen/photovoltaik-e.html Polymer Solar Cells. Wikipedia Foundation. April 28, 2009. http://en.wikipedia.org/wiki/Polymer_ solar_cell Shapleigh, Eliot. Texas Senate Passes Omnibus Solar Bill to Create Incentive Program for Texas Homeowners. April 21, 2009.

Senator Eliot Shapleigh. http://shapleigh.org/ news/3028-texas-senate-passes-omnibussolar-bill-to-create-incentive-program-for-texashomeowners Silicon Valley Toxics Coalition Stopping the Solar Photovoltaic Waste Stream Before It Starts. Solar Photovoltaic End-of-Life. October 15, 2008. Texas Solar Energy Society. http:// www.txses.org/solar/content/solar-photovoltaicend-life Texas Longhorns. Official Site of the Texas Athletics. CBS. 2009. http://www.texassports. com/ The German Energy Society. Planning and Installing Photovoltaic Systems for the reticulated structure for a free-form surface. Earthscan.

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2008.

Thin-film Technologies- Dye Solar Cell. 2009.

Ecospeifier. Accessed May 6, 2009. http://www. ecospecifier.org/products/public/thin_film_ technologies_dye_solar_cell Thin Film. U.S. Department of Energy - Energy Efficiency and Renewable Energy. Solar Energy Technologies Program. January 5, 2006. http:// www1.eere.energy.gov/solar/thin_films.html U.S Department of Energy. Tax Breaks for Businesses, Utilities, and Governments.

Accessed May 6, 2009. http://www.energy.gov/ additionaltaxbreaks.htm Usvat Corporation Energy Department.

Mathematics Magazine. Accessed May 6, 2009. http://www.mathematicsmagazine.com/energy/ what_are_photovoltaics.htm Ut Campus Environmnetal Center. Accessed May 7, 2009. http://www.utenvironment.org/content/ index.php?option=com_frontpage&Itemid=1 Welcome to UTake Charge. 2007. University of Texas at Austin. http://www.utexas.edu/ utakecharge/about/ Raffaelle, Ryne. Solar & Alternative Energy: Hybrid Nanomaterials Improve Solar Cell Efficiency. 2006. The International Society for Optical Engineering. Accessed May 6, 2009. http://spie.org/x8613.xml?ArticleID=x8613

7.3 Illustrations Figure 1: Darrell K Royal-Texas Memorial Stadium. Facilities. 2009. http://www.texassports. com/facilities/royal-memorial-stadium.html Figure 2: National Renewable Energy Laboratory (NREL). Accessed May 10, 2009. http://upload.wikimedia.org/wikipedia/en/e/e3/ PVeff%28rev110707%29d.jpg.

Figure 3: The German Energy Society. Planning and Installing Photovoltaic Systems for the reticulated structure for a free-form surface.

Earthscan. 2008.

Figure 4: The German Energy Society. Planning and Installing Photovoltaic Systems for the reticulated structure for a free-form surface.

Earthscan. 2008.

Figure 5: Third Generation Photovoltaics.

School of Photovoltaic and Energy Engineering.

University of new South Whales. Australia.

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Photovoltaic Application for the Scoreboard

Accessed May 10, 2009. http://www.pv.unsw. edu.au/Research/3gp.asp

http://www.treehugger.com/files/2008/02/ screen-printed_solar_cells.php

Figure 6: Solar Panel, Solar Home Lighting.

Alibaba.com. India. Accessed May 10, 2009. http://www.alibaba.com/product/in104239641104029826-100775709/Solar_Panel_Solar_ Home_Lightning.html

Figure 18: Daylife. Accessed May 10, 2009. http://www.daylife.com/photo/08gpft19IZbPw

Figure 7: The German Energy Society. Planning and Installing Photovoltaic Systems for the reticulated structure for a free-form surface.

Earthscan. 2008.

Figure 20: Single Axis Tracking System. Linak.

2008. http://www.solar-tracking.com/

Figure 8: The German Energy Society. Planning and Installing Photovoltaic Systems for the reticulated structure for a free-form surface.

Earthscan. 2008.

Figure 9: The German Energy Society. Planning and Installing Photovoltaic Systems for the reticulated structure for a free-form surface.

Earthscan. 2008.

Figure 10: The Solar Guys. Solarise with the Solar Guys. Brisbane. Accessed May 10, 2009. http://www.solarguys.com.au/solar_power_ photovoltaics_thinfilm.htm Figure 11: Roll to Roll Process. Konarks’a OPV Module. Konarka Technologies. Accessed May 10, 2009. http://www.konarka.com/index.php/ site/tech_roll_to_roll_process/ Figure 12: Solar Cell Printing: A Hot Application.

Graphic Arts Online. 10/8/2008. http://www. graphicartsonline.com/article/CA6602969.html Figure 13: Dye-Sensitized Solar Cell. Accessed May 10, 2009. http://www.postech.ac.kr/chem/ mras/eunju.htm Figure 14: New Type Of Solar Cells Achieve Record Of Efficiency & Performance. November 6, 2008. http://www.devicedaily.com/tag/solarpower Figure 15: ColorSol- Sustainable Product Innovations through Dye Solar Cells. Federal Ministry of Education and Research. Accessed May 10, 2009. http://www.fona.de/en/ forum/2007/exhibition.php?we_objectID=5248& pic=3&y=2007 Figure 16: Applications- Solar Energy. Solaris Nanosciences. Accessed May 10, 2009. http:// www.solarisnano.com/solarenergy.php Figure 17: Jacquot, Jeremy Elton. Los Angeles on 02. 1.08 Screen-Printed Solar Cells Come in a Variety of Colors and Patterns, Ideal for Building . Treehugger- A Discovery Company.

Figure 19: Single Axis Tracking System. Linak.

2008. http://www.solar-tracking.com/

Figure 21: The German Energy Society.

Planning and Installing Photovoltaic Systems for the reticulated structure for a free-form surface.

Earthscan. 2008.

Figure 22: The German Energy Society.

Planning and Installing Photovoltaic Systems for the reticulated structure for a free-form surface.

Earthscan. 2008.

Figure 23: Texas Solar Energy. State Energy Conservation Office. Accessed May 6, 2009. http://www.seco.cpa.state.tx.us/re_solar.htm Figure 24: Poe, Vanessa. The University of Texas at Austin. September 2008.

Figure 25: Poe, Vanessa. The University of Texas at Austin. September 2008.

Figure 26: The Solarserver. Forum for Solar Energy. Solar Collectors. http://www.solarserver. de/wissen/sonnenkollektoren-e.html Figure 27: http://www.austinsmartenergy.com/ divison.php?page=learn_more&sub=fact_sheet Figure 28: The German Energy Society.

Planning and Installing Photovoltaic Systems for the reticulated structure for a free-form surface.

Earthscan. 2008.

Figure 29: Poe, Vanessa. The University of Texas at Austin. September 2008.

Figure 30: America’s Best Sports Colleges.

Sports Illustrated. October 7, 2002. http:// sportsillustrated.cnn.com/si_online/ news/2002/10/01/1_10/ Figure 31: Sweed, McCoy get SI for Kids cover spot. Wednesday, July 18, 2007. http://www. statesman.com/blogs/content/shared-gen/blogs/ austin/longhorns/entries/2007/07/18/ Figure 32: The University of Texas at Austin.

Austin Texas. Plans received March 10, 2009.

Figure 33: Poe, Vanessa. The University of Texas at Austin. March 2009.

UTSoA - Seminar in Sustainable Design

Photovoltaic Application for the Scoreboard

Figure 34: Aggie constructor overseeing renovation to UT stadium. archone. Newsletter of the college of Architecture at Texas A&M. http:// archone.tamu.edu/college/news/newsletters/ spring2008/stories/aggieUTstadium.html

Figure 53: Arcangeli, Gregory and Vanessa Poe. The University of Texas at Austin. April 2009.

Gnant, Chad. Graduate School, The University of Texas at Austin. chad.gnant@gmail.com

Figure 54: Arcangeli, Gregory and Vanessa Poe. The University of Texas at Austin. April 2009.

Holdenried, Erin. Graduate School, The University of Texas at Austin. erin.holdenried@ gmail.com

Figure 35: Gnant, Chad. The University of Texas at Austin. April 2009.

Figure 55: Holdenried, Erin and Chad Gnant.

The University of Texas at Austin. April 2009.

Figure 36: Gnant, Chad. The University of Texas at Austin. April 2009.

Figure 56: Holdenried, Erin and Chad Gnant.

The University of Texas at Austin. April 2009.

Figure 37: Gnant, Chad. The University of Texas at Austin. April 2009.

Figure 57: Holdenried, Erin and Chad Gnant.

The University of Texas at Austin. April 2009.

Figure 38: Gnant, Chad. The University of Texas at Austin. April 2009.

Figure 58: Allianz Arena. World Stadium.

Accessed May 10, 2009. http://www. worldstadiums.com/stadium_menu/architecture/ stadium_design/munchen_allianz.shtml

Figure 39: Poe, Vanessa. The University of Texas at Austin. March 2009.

Figure 40: Arcangeli, Gregory. and Erin Holdenried. The University of Texas at Austin.

April 2009.

Figure 41: Gnant, Chad and Erin Holdenried.

The University of Texas at Austin. April 2009.

Figure 42: Arcangeli, Gregory. and Erin Holdenried. The University of Texas at Austin.

April 2009.

Figure 43: Gnant, Chad and Erin Holdenried.

The University of Texas at Austin. April 2009.

Figure 44: Holdenried, Erin. The University of Texas at Austin. April 2009.

Figure 45: Holdenried, Erin. The University of Texas at Austin. April 2009.

Figure 46: Gnant, Chad. The University of Texas at Austin. April 2009.

Figure 47: Gnant, Chad. The University of Texas at Austin. April 2009.

Figure 48: The Group. The University of Texas at Austin. April 2009.

Figure 49: Arcangeli, Gregory. The University of Texas at Austin. April 2009.

Figure 50: Arcangeli, Gregory. The University of Texas at Austin. April 2009.

Figure 51: Gnant, Chad and Gregory Arcngeli.

The University of Texas at Austin. April 2009.

Figure 52: Arcangeli, Gregory. The University of Texas at Austin. April 2009.

Klingner, Richard. L. P. Gilvin Centennial Professor in Civil Engineering, PHD. Department of Civil, Architectural and Environmental Engineering, Cockrell School of Engineering. +1 512 232 3597. klingner@mail.utexas.edu Lang, Werner. Associate Professor, PHD. School of Architecture. +1 512 471 5663. lang@ austin.utexas.edu Libby, Leslie. Austin Energy. 512 482 5390. www.austinenergy.com

Figure 59: Sir Norman Foster does it again, and again, and‌ Museum Lab. The New York Times, November 19, 2007. http://www.museumlab. org/2008/02/07/sir-norman-foster-does-it-againand-again/

McCalla, Andrew. Meridian Energy Systems.

512 448 0055. www.meridiansolar.com

Figure 60: Sanchez-Alvarez, J, S. Stephan, and K. Knebel. Reticulated Structures on Free-Form Surface.

Whitsett, Dason. Lecturer, MS. School of Architecture. dmw@mail.utexas.edu

Figure 61: Novum Structures. Acessed May 10, 2008. http://www.novumstructures.com/novum/ Figure 62: Holdenried, Erin. The University of Texas at Austin. April 2009.

Poe, Vanessa. Graduate Student, The University of Texas at Austin. hokie.poe@gmail.com.

Kraal, Steven. Senior Associate Vice President, PHD. Office of Campus Planning & Facilities Management.+1 512 475 6976. sakraal@mail.utexas.edu

Figure 63: Holdenried, Erin. The University of Texas at Austin. April 2009.

Figure 64: Arcangeli, Gregory. The University of Texas at Austin. April 2009.

Figure A-65: Campus Sustainability Report Card. 2008 Sustainable Endowments Institute. http://www.greenreportcard.org/ Figure A-66: Gnant, Chad. The University of Texas at Austin. April 2009.

Figure A-67: Sunpower. SPR-305-WHT. Document #001-42209 Rev **A4_en. January 2008. sunpowercorp.com Figure A-68:

7.4 Contacts Arcangeli, Gregory. Graduate School, The University of Texas at Austin. greg.arc@gmail. com

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7.5 Appendix

50

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in g tI n Tr vo an lv em sp or en ta t En tio do n w m In en ve tT st m r Sh en ans tP p ar rio a re En eh nc ga old riti y es ge er m en t en

ld Bu i

St ud

G re

en

R & od

Fo

at e

C

ec

ha

yc

ng

n C

in

lim

is

tra

tio

re Sc o ll ra

Ad m

O ve

r Ye a

lin

e

g

&

En e

rg

y

Figure A-65: The Big 12 College Sustainability Report Card

C+

Further explanation from left to right Administration- Examines sustainability policies and commitments by school administrators and trustees; Climate Change & Energy- Looks at energy efficiency, conservation, commitment to emissions reductions, and use of renewable energy on campus; Food & Recycling- Evaluates dining services policies, including recycling and composting programs; Green Buildings- Recognizes campus-wide green building guidelines and green building design for new and existing buildings; Student Involvement- Looks at student participation in sustainability initiatives and support for these activities by school administrators; Transportation- Focuses on alternative transportation for students, faculty, and staff, as well as alternative fuel or hybrid technology for campus fleets; Endowment Transparency- Addresses accessibility to endowment investment information and shareholder proxy voting records; Investment Priorities- Considers prioritization of return on investment, investment in renewable energy funds, and investment in community development loan funds; Shareholder Engagement- Looks at shareholder proxy voting practices, including opportunities for student, faculty, and alumni participation.

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Figure A-66: Shadow study

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Photovoltaic Application for the Scoreboard

Figure A-67: Solar Vial Panels

305 SOLAR PANEL EXCEPTIONAL EFFICIENCY AND PERFORMANCE

BENEFITS Highest Efficiency Panel efficiency of 18.7% is higher than any commercially available competitor panel.

More Power SunPower 305 delivers 50% more power per unit area than conventional solar panels and 100% more than thin film solar panels.

Reduces Installation Cost More power per panel means fewer panels per install. This saves both time and money.

Reliable and Robust Design Proven materials, tempered front glass, and a sturdy anodized frame allow panel to operate reliably in multiple mounting configurations.

The SunPower 305 Solar Panel provides today’s highest efficiency and performance. Utilizing 96 next generation SunPower all back-contact solar cells, the SunPower 305 delivers an unprecedented total panel conversion efficiency of 18.7%. The 305 panel’s reduced voltagetemperature coefficient and exceptional low-light performance attributes provide outstanding energy delivery per peak power watt.

SunPower’s High Efficiency Advantage - Up to Twice the Power Comparable systems covering 1000 m² / 10,750 ft² Thin Film

Conventional

SunPower

Watts / Panel

65

165

305

Efficiency

9.0%

12.0%

18.7%

kWs

90

120

187

9

SPR-305-WHT 00000220

0

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305 SOLAR PANEL EXCEPTIONAL EFFICIENCY AND PERFORMANCE

IV Curve

Electrical Data Measured at Standard Test Conditions (STC): irradiance of 1000/m2, air mass 1.5 g, and cell temperature 25° C

Pmax

305 W

7.0

Rated Voltage

Vmp

54.7 V

6.0

Rated Current

Imp

5.58 A

5.0 Current (A)

Peak Power (+/-5%)

Open Circuit Voltage

Voc

64.2 V

Short Circuit Current

Isc

5.96 A

Maximum System Voltage

IEC, UL

1000 V, 600 V

Power

–0.38% / °C

Voltage (Voc)

–176.6 mV/°C

1000 W/m² 800 W/m²

4.0 3.0

500 W/m²

2.0 1.0

Temperature Coefficients

Current (Isc)

1000 W/m² at 50 °C

0.0 0

10

20

30

40

50

60

70

Voltage (V)

3.5 mA/°C

Current/voltage characteristics with dependence on irradiance and module temperature.

Series Fuse Rating

15 A

Peak Power per Unit Area

187 W/m², 17.4 W/ft²

Mechanical Data Solar Cells

96 SunPower all back-contact monocrystalline

Front Glass

4.0 mm (5/32 in) tempered

Junction Box

IP-65 rated with 3 bypass diodes

Output Cables

900 mm length cables / Multi-Contact connectors

Frame

Anodized aluminum alloy type 6063

Weight

24 kg, 53 lbs

Tested Operating Conditions Temperature

–40° C to +85° C (–40° F to +185° F)

Max load

240 kg/m2 (2400 Pascals) front and back

Impact Resistance

Hail – 25mm (1 in) at 23 m/s (52 mph)

Warranty and Certifications Warranty

25 year limited power warranty 5 year limited product warranty

Certifications

IEC 61215 , Safety tested IEC 61730; UL listed (UL 1703), Class C Fire Rating

Dimensions 180 (7.04)

mm (in)

1200

Ø 4.2 (.16)

(47.24)

( Ground )

2X Ø 4.2 (.16) ( Ground )

1002 (39.45)

1046 (41.18)

915

1559 (61.39)

(36.02)

46 (1.81) Ø 4.2 (.16)

322 (12.69)

8X Ø 6.6(.26)

( Ground )

CAUTION: READ SAFETY AND INSTALLATION INSTRUCTIONS BEFORE USING THE PRODUCT. Go to www.sunpowercorp.com/panels for details About SunPower SunPower designs, manufactures and delivers high-performance solar electric technology worldwide. Our high-efficiency solar cells generate up to 50 percent more power than conventional solar cells. Our high-performance solar panels, roof tiles and trackers deliver significantly more energy than competing systems. © January 2008 SunPower Corporation. All rights reserved. Specifications included in this datasheet are subject to change without notice.

Document #001-42209 Rev **A4_en

sunpowercorp.com

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Figure A-68: Solar shading on Austin’s City Hall

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College Sustainability Report Card 2010

Photovoltaic Application for the Scoreboard

Administration: B

Student Involvement: A

School details:

The university president has approved a sustainability policy. UT Austin’s sustainability staff include the director of sustainability and the alternative transportation manager. The President’s Task Force on Sustainability recommends policies to the administration. Nearly all new appliance and computer purchases are Energy Star-qualified.

The Campus Environmental Center is the largest environmental organization on campus and also offers paid positions for students. The group’s focus is on collaborating with university operational groups to institute change in sustainable practices. The annual Do it in the Dark energy competition encourages conservation.

Grade higher than last year

Climate Change & Energy: C

Transportation: A

Endowment: $16,111 million as of June 30, 2008

Energy efficiency upgrades include the installation of variable frequency drives as well as a quench valve system that provides over $1 million in natural gas savings annually. Information technology services is in the process of constructing a more efficient data center that will raise efficiency to 98 percent and will also reduce the overall energy needed to cool the machines.

All community members are eligible for carpool incentives, and city buses are free for anyone with a university ID card.

UT also offers shuttle service between residential areas and outlying academic locations. The Orange Bike Project offers bicycle rentals free of charge. The master plan calls for pedestrian- and bike-friendly improvements in some areas of the campus.

Campus Survey: Yes

Food & Recycling: B

Endowment Transparency: A

Dining Survey: Yes

UT Austin spent approximately 2 percent of its budget on locally grown food during the 2008-2009 academic year, and close to 6 percent on locally processed items.

The university also purchases organic items, cage-free eggs, and hormonefree chicken. Vegan options are served daily. Customers receive discounts when they bring reusable bags and mugs. The Trash to Treasure Donation Drive collects unwanted items from students every spring.

The University of Texas Investment Management Company makes a list of investment holdings available online, and proxy voting records are sent to individuals upon request, as per open record law.

The University of Texas at Austin

Overall Grade: B-

Location: Austin, Texas Enrollment: 45,089 Type: Public

Endowment Survey: No Student Survey: Yes

Data compiled from independent research.

For information on data collection and evaluation, please see the Methods section.

Green Building: B

**Addendum post publication www.greenreportcard.org

UT intends to achieve LEED Silver or better on newly constructed buildings and has also pledged to use best practices in the product selection, waste management, and recycling in all new construction projects. The university is hoping for Goldlevel certification for the Hearst Student Media Center, slated for completion in fall 2009. Water-saving retrofits include lowflush toilet valves and shower heads.

Investment Priorities: C The University of Texas Investment Management Company aims to optimize investment return and has not made any public statements about investigating or investing in renewable energy funds or community development loan funds.

Shareholder Engagement: F The University of Texas Investment Management Company provides its investment managers with general guidelines that determine its proxy votes on social and environmental resolutions, and provides its investment managers with specific corporate governance guidelines that determine its proxy votes on those matters.

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