Solar Cells Info

Posted by Martin LaMonica /November 9, 2007
Source: CNet.com news
http://www.news.com/8301-11128_3-9814084-54.html

The National Renewable Energy Laboratory gave out awards on Thursday to two companies developing solar electric cells they hope will bring a breakthrough in solar panel efficiency.  Top prize went to Wakonda Technologies, based in upstate New York, which is commercializing “virtual single crystal” technology.

The efficiency of converting sunlight to electricity in solar cells made from silicon–the most common material today–are in the 15 percent to 20 percent range. Companies are trying to manufacture cells out of other materials–copper-indium-gallium-diselenide or cadmium-telluride–to be more cost-effective. The efficiency and cost-effectiveness of commercial cells is expected to improve incrementally over the next several years. But at the same time, researchers are pursuing techniques to boost efficiency dramatically.

Based on information posted on its Web site, Wakonda is trying to make high-efficiency solar cells more flexible so that they can be integrated into roof shingles and other structures. “Wakonda is developing a revolutionary method to significantly reduce raw materials cost–the primary cost driver in production of inherently high efficiency III-V cells. Our virtual single crystal uses a proprietary surface treatment that allows a low cost, commercial metal foil to simulate an expensive single crystal wafer,” according to its Web site. A company representative wasn’t available by phone this morning.

Another company swinging for the fences in solar cell efficiency won second prize in the NREL competition, which was announced in conjunction with its Industry Growth Forum this week. Bandgap Engineering, based in Westwood, Mass., is pursuing a “third-generation” solar cell meant to push efficiency to over 50 percent, according to the company’s Chief Technology Officer Marcie Black.

Black pitched to investors at the Clean Energy Conference in Boston recently where she detailed the technology her company is pursuing. “We are nano-engineering silicon so it is optimized for electricity conversion,” she said.

The technique calls for putting an intermediate band in silicon solar cells to improve efficiency without generating too much heat, she said. In the scheme of things, these winners aren’t walking away with a whole lot of money. Wakonda won $10,000 and Bandgap Engineering got $1,500. The third winner–solid-state lighting company Albeo Technologies–also got $1,500.