Solar Electric Panels > New Developments
Intalled 11/8/96

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These are VERY interesting to us, however as I am sure you are aware from time to time rumors go around and then nothing, therefore just want you to know that we are on top of it and will keep you informed, we are not able to know for sure about any of these as we have not tested any of them and actually have not seen them - so take it for what it's worth. We are happy as this may be the brake through we all have been wanting in order for the price of alternative energy to go down and our planet can use less polluting stuff . . . We would appreciate your comments and also anything else you know about this or other new items -

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• Solar Chip
• Photovoltaic Panels Improve Efficiency
• Tandem Solar Cells Capture More Energy

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Subject - SOLAR CHIP

. . . . . . . . . We have received the following information that we want to pass along to you - we are still researching this and just wanted you to know what we know - and we will keep on top of this to keep you informed - as usual anything that you know new let us know so we can pass it along to our interested newsletter readers . . . . . . . . . . . We understand that a new patent awarded in May 1995, that could make solar cells economically viable at 20-40 cents a watt? That's no typo! I recently found the patent by way of its owner, Dr. James Van Vechten, from Oregon State Uni........

................ the following was taken from the radio program ...."Pulse of the Planet".... is presented by DuPont to recognize the role of research and technology in our daily lives.

"Dr. James Van Vechten (VECK-ten) is a professor of electric and computer engineering at Oregon State University. He says that by connecting the chips, the system can produce a hundred Watts of energy per square meter. But perhaps the most attractive feature of the material is its durability.....

A new invention is giving the cause of solar power an encouraging shot in the arm. Using silicon and a special type of cement, buildings, railroad ties, and shingles can now be turned into solar energy collectors. .......

(sorry no audo) "We're listening to the sounds of a sieve that's sifting out uniform pieces of silicon, the same material that's used in computer chips. They're going to be mixed with an extra strong cement that's molded onto a sheet, forming the basic structure of what's called a "solar chip."

"The solar chips work by absorbing the sunlight and producing a current that flows on the two outer surfaces of the sheet."

"Our solar cells differ from the conventional ones in that they're made of very robust material. They do not need to be put in a package and guarded outdoors. They're not susceptible to being stolen, and they are quite a little bit cheaper than existing solar cells. Existing solar cells, commercially, are selling for about six dollars per Watt. And we hope to be able to offer ours, in maybe three years time, at twenty cents a peak Watt, and in a form where they can be simply applied to the sides of buildings, railroad ties, and roofing shingles without a package over them and with no protection."

.............Another program .......

"Dr. James Van Vechten (VECK-ten) is a professor of electric and computer engineering at Oregon State University. He's developing thin solar panels made with a mixture of silicon grains and a high-strength cement. The new panels use forty percent less silicon than conventional solar cells.

"This is because the normal process first makes the electronic grade polycrystalline silicon into wafers, which involves a waste of about 78 percent of all the silicon they begin with. And it's that 78 percent that initially we would take and use for our process. Also the conventional cells are about eleven times thicker than they need to be, from an electrical point of view. Less than ten percent of the silicon in the conventional cells is actually involved in making the energy. The rest is just there for mechanical support. We use our very strong cement and a concrete substrate they're put on for the mechanical support."

"Dr. Van Vechten says that these solar cells can be attached to just about any cement structure, such as railroad ties and buildings. They may also help industry to reuse the roughly ten million metric tons of silicon thrown away every year.

"If our project is successful we will be able to turn that into an energy source equivalent to eight standard nuclear reactor stations per year. But also we'll be saving the landfills for materials that actually need to be in there."

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Photovoltaic Panels Improve Efficiency

A 3-year partnership between NREL and United Solar Systems Corporation (Troy, Michigan) came to fruition when the company announced plans to build one of the largest photovoltaic (PV) production facilities in the world. United Solar is a joint venture between Energy Conversion Devices of Troy, Michigan, and Canon, Inc., of Japan.

Located in Newport News, Virginia, the $30-million plant will create 300 to 400 new jobs and dramatically reduce the cost of PV-produced electricity. Using a patented, continuous-roll process, United Solar will manufacture 10 megawatts of PV panels per year. The panels are based on thin films of amorphous silicon, which achieved a record 10.2% conversion efficiency.

The high efficiencies, plus the production facility's economy of scale, are expected to reduce the cost of PV-generated electricity by 40%, from about $0.25 per kilowatt-hour to $0.16 per kilowatt-hour.

The United Solar panels will be lightweight and flexible, with a broad range of consumer applications; among them: stand-alone power systems, replacing glass in the walls of commercial buildings, and replacing roofing shingles on homes.

Possible spin-off technologies include semiconductor-based components for photocopiers, fax machines, and flat-panel displays.

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Tandem Solar Cells Capture More Energy

Photovoltaics has powered satellites in space since the beginning of the space age. The two most prevalent solar cell materials for space applications are silicon and gallium arsenide. Both materials, however, degrade under the intense radiation found in space. NASA Lewis Research Center in Cleveland, Ohio, and the Naval Research Laboratories in Washington, D.C., contracted NREL to develop a radiation-resistant solar cell to power satellites and other space- based devices. NREL researchers designed a tandem, or cascade, solar cell, in which two cells made of different materials are placed one top of the other. The top cell captures and converts high- energy light, allowing low-energy light to "cascade" into the bottom cell for absorption and conversion to electricity. Tandem devices, therefore, capture more of the solar spectrum and can be more efficient than single-junction cells.

For the top cell, NREL researchers used indium phosphide (InP), which is 50% more resistant to radiation damage than silicon is. Gallium indium arsenide (GaInAs)was chosen as the bottom cell, because its lattice structure matched that of InP.

The tandem device achieved a world record 31.8% conversion efficiency. The higher efficiency means a potential reduction in system size--a major advantage when delivering payloads into space. NREL's InP/GaInAs tandem solar cell has-been tested on NASA's space shuttle and the British satellite STRV-1.

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