Calisolar scores funding for "dirty" silicon plant

Solar cell manufacturer Calisolar has reportedly scored $102m (£64m) in funding for a manufacturing plant that may use its so-called "dirty silicon" technology.

Calisolar says it has developed a way to process metallurgical silicon for use in the solar cells that it manufactures. This cheaper lower-grade silicon is not normally suitable for solar cells, and as such a means of processing it for use in cells could give the company a competitive edge in a market where prices for higher-grade silicon have been soaring.

The company would not confirm that it had raised the money, but private equity blog peHUB obtained the full text of a Regulation D filing with the SEC which it said confirmed a $102m funding round.

According to the filing, Calisolar raised $51.9m in Series B preferred stock funding, and another $50m in convertible securities. Funding came from Hudson Clean Energy, along with funders Advanced Technology Ventures and Globespan Capital Partners.

Chief executive Roy Johnson had been looking for funding during the summer to open a commercial plant in California. He told BusinessGreen.com that the company would be making several announcements in the next few months.

Silicon has been in short supply for solar manufacturers in recent months, confirmed Martin Meyers, an author of the Solar Annual produced by Photon Consulting, which tracks silicon pricing.

"Demand for photovoltaics has grown very quickly in recent years primarily as a result of supportive government policies around the globe, rising grid prices and low long-term interest rates," he said. "Furthermore, until recently, silicon suppliers, who have traditionally served the semiconductor rather than the solar industry, have not had sufficient confidence in the solar sector's growth to expand capacity for solar customers."

Meyers added that the shortage was likely to continue in the future. "We expect demand for PV will continue to grow very rapidly and we expect silicon to remain the fundamental bottleneck in the supply chain despite very rapid silicon capacity growth in the next few years," he said, adding that 2009 prices would remain at roughly the same levels experienced during this year.