"SUNNYVALE, Calif. -- A Silicon Valley company is claiming a breakthrough in a decades-old quest to develop fuel cells that can supply affordable and relatively clean electricity. Google, Bank of America, Wal-Mart and other large corporations have been testing the devices, which will be formally introduced on Wednesday.
The start-up, Bloom Energy, has raised about $400 million from investors and spent nearly a decade developing a new variety of solid oxide fuel cell, considered the most efficient but most technologically challenging fuel-cell technology.
K. R. Sridhar, Bloom’s co-founder and chief executive, said devices made by his company were generating electricity at a cost of 8 to 10 cents a kilowatt hour, using natural gas. That is lower than commercial electricity prices in some parts of the country. "
Todd Woody reports for the New York Times February 23, 2010. 
"A Secretive Start-Up Raises the Curtain" (Green Inc.)