Sierra Solar Bags $40M In Second Round Of Funding

California-based Sierra Solar has raised $40 million in a second round of funding to invest in the development of a cheaper thin-film photovoltaic cell.

The investors have not been named, but Sierra previously raised $7.1 million from GSR Ventures and DragonTech Ventures. Sierra’s founders have said they hope to raise $60 to $70 million over three rounds of funding.

Sierra Solar manufactures its products in China, to keep prices down. It claims its cells are 16% to 17% efficient (compared to the 15% average for thin-film modules). The company sells excess power back to local utilities and says its processes could eventually reduce the cost of solar power by $1 per watt.

Sierra also produces long-storage batteries, refrigeration units, water pumps, solar ovens and solar panels.