* Construction of solar plant created about 350 jobs
* Solar plant seen fully in service Dec. 2013
Oct 25 (Reuters) - U.S. power company NRG Energy Inc said it delivered the first 22 megawatts (MW) of the 250-MW California Valley Solar Ranch to the California power grid on Wednesday.
The California Valley project is a photovoltaic solar power plant, NRG said in a release late Wednesday, which has created about 350 jobs since construction started in September 2011.
The project was expected to inject $315 million into the local economy over its two-year construction period and was expected to be fully online by December 2013, NRG said.
Once complete, California Valley will power a yearly average of 100,000 homes.
NRG did not say how much the California Valley project would cost. Last year in September, California solar power company SunPower Corp, which designed the project, received a $1.2 billion federal loan guarantee for the plant.
According to industry estimates, building a solar photovoltaic plant costs about $4,700 per kilowatt, so the California Valley project likely cost about $1.2 billion.
Renewable power generates about 13 percent of the nation's total electricity but most renewable energy (about 63 percent) comes from hydropower, according to federal energy data.
The use of solar power is growing due in part to state and federal subsidies and rules requiring the use of more renewables, but in 2011 still represented less than 1 percent of total renewable power sources, according to the U.S. Energy Information Administration (EIA).
The California Valley project will help power companies in California meet the state's aggressive renewable portfolio standard, requiring 33 percent of the power the utilities deliver to customers comes from renewable sources by 2020.
California power company PG&E Corp will buy the power from California Valley under a 25-year purchase agreement.
The solar plant is located in San Luis Obispo County about 100 miles (160 km) northwest of Los Angeles.
NRG acquired California Valley on September 30, 2011.
SunPower was working with California based construction and engineering firm Bechtel to help engineer and build the project.
Once complete, NRG and SunPower will jointly operate and maintain California Valley for two years, after which NRG will assume sole responsibility.
NRG has over 2,000 MW of photovoltaic and solar thermal projects under development or in construction in the U.S. Southwest.
SunPower has about 190 MW of solar projects at locations across the United States with more than 1,000 MW under contract.