Californian utility inks solar mega-deal

The California Public Utilities Commission is examining whether to give the go-ahead to a solar energy deal that could power almost a million Californian homes, after Southern California Edison this week reached an agreement with BrightSource Energy for seven solar projects totalling 1.3 Gigawatts of energy.

The projects would use BrightSource's Luz Power Tower 550, which employs thousands of mirrors to direct sunlight to the top of a tower. The heat turns water in a boiler on top of the tower into steam, which rotates a turbine.

If all the projects are approved, they will produce 3.7bn kilowatt-hours of energy annually, according to the firms, which say that this would generate enough energy for 845,000 homes. The projects would also avoid two million tons of carbon emissions per year – equating to 0.033 per cent of the US total for 2007.

Brightsource said that the first project in Ivanpah, California could be producing 100 megawatts of energy by 2013.

Hailing the contract as a "landmark agreement" BrightSource chief executive John Woolard said the huge deal illustrated that solar thermal technologies were increasingly regarded as "a reliable source of utility-scale renewable power".

SCE currently buys 16 per cent of its energy renewable supplies, and says that other contracts due to come online will bump that number to 20 per cent – a requirement that must be met by next year under California's Renewable Portfolio Standard. The standard calls for a further 13 per cent of energy to come from renewables by 2020. The solar deal with BrightSource would boost the solar contribution to its renewable portfolio from 12.2 per cent to 56 per cent.

According to the latest available figures for carbon emissions in California from 2004, the state produces a quarter of its carbon emissions from in-state and imported electricity production.

In related news, Sierra Solar became the latest thin-film solar cell manufacturer to secure fresh financial backing, reportedly raising $40m (£27m) in a second funding round to help produce cheaper thin-film solar cells.