This is an excerpt from EERE Network News, a weekly electronic newsletter.
SunPower Pilot Line Produces 20-Percent-Efficient Solar Cell
Crystalline-silicon (c-Si) solar cells continue to be the photovoltaic industry's workhorse, and companies are still striving to squeeze more power out of every c-Si cell. The latest milestone was announced on May 12th by SunPower Corporation, which produced a solar cell that's more than 20-percent efficient, that is, under controlled test conditions it converts more than one-fifth of the sunlight hitting it into electricity. SunPower achieved the high efficiency through a back-contact design that keeps the wiring behind the cell and allows the maximum surface area to be exposed to sunlight. The company claims that the cell could deliver 3 kilowatts of power in less than 17 square meters (183 square feet, which is a square measuring 13.5 feet on each side). SunPower is currently manufacturing the cell on a pilot-scale line capable of producing only 2 megawatts of solar cells per year, but the company plans to begin full-scale production next year. See the Sun Power press release and the accompanying solar cell photo.
The SunPower news comes just two weeks after Sharp Corporation introduced a c-Si solar module with a 17.4-percent efficiency, allowing a 3-kilowatt solar power system to fit in only 17.3 square meters (186 square feet). Sharp is currently selling the module only in Japan. See the Sharp press release.