Solar technology provider SunPower has secured a conditional commitment of loan guarantee of approximately $1.187bn from the US Department of Energy (DOE) for a 250MW (AC) power plant in southern California.

SunPower will design, build, and initially operate and maintain the California Valley Solar Ranch power plant, which will be owned and financed by NRG Solar.

The company plans to begin construction in the second half of 2011 and a portion of the facility is expected to commence operations by the end of year, with the final completion slated for 2013.

The photovoltaic (PV) solar power plant is expected to power approximately 100,000 homes in San Luis Obispo County.

NRG Solar president Tom Doyle said the offer of a conditional commitment for a loan guarantee from the DOE’s Loan Programs Office will support the project to make a substantial contribution to California’s effort to generate 33% of its electricity from renewable sources by 2020.