Searching for solar’s feedstock

Researchers at UC Berkeley, and the Lawrence Berkeley National Laboratory (LBNL) have begun a project that ultimately hopes to find a replacement for silicon in the solar industry.  The use of silicon is proving to be a limiting factor in the solar industry reaching grid-parity.  Their report was released through the American Chemical Society in the Environmental Science and Technology Journal and looked extensively into alternative feedstocks for the solar industry.  The team of researchers began by surveying 23 promising materials before selecting nine that produced “a significant raw material cost reduction over traditional crystalline silicon”.

In order for solar power to become competitive with oil, coal, and gas, it is necessary to lower the cost per kilowatt-hour either through improvements in the efficiency of conversion or by using less expensive materials to make the solar cells/films.  Up until now, silicon cells have been the mainstay of the industry because of their higher efficiency yields.  Pure silicon, though, is more expensive than the silicon blends or the alternative materials being used in thin film production.

There are numerous companies springing up that are bringing these alternative materials into the solar market, but the solar industry seems to be having trouble finding the right feedstock.  Solar has been experiencing problems reaching cost-parity with fossil fuels because of the high prices associated with processing silicon specifically tailored to allow for high efficiency conversion rates.  Up until the recent introduction of thin films, the solar industry was solely relying on feedstock from the same supply chain used in the semiconductor industry.  This was causing numerous shortages in silicon supply and dramatic cost increases in an industry that was struggling to keep costs down in an effort to survive.

According to Eicke Weber, on of the researchers from UC Berkeley, “photovoltaics could grow much faster if researchers and manufacturers could further reduce the cost of solar cells and overcome the shortage in the high-quality, semiconductor-grade silicon used presently to make commercial solar cells".  The silicon that is currently being used in large quantities in the solar industry is usually the high quality stuff because the monocrystalline structure produces cells with higher efficiencies.  The more pure polysilicon is also used technical gadgetry.

Monocrystalline silicon “is pulled as a single crystal; the internal crystalline structure is completely homogenous”.  This kind of silicon is used in...

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http://www.examiner.com/x-2903-Energy-Examiner
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