The world's biggest solar power project was approved by the U.S. Interior Department, whose electricity is enough to power around 750,000 average American homes in southern California.

The project, a joint venture of Solar Millennium AG and Ferrostaal AG will consist of four concentrated solar electric generation facilities that would be able to produce up 1,000 megawatts of power. That is equal to the turbine output of a nuclear power plant or a large modern coal-fired power plant.

"The Blythe Solar Power Project is a major milestone in our nation's renewable energy economy and shows that the United States intends to compete and lead in the technologies of the future," said U.S. Interior Secretary Ken Salazar.

The project will be built in four units of 250mw each. The first 250mw should be up and running in 2013 and the second one in 2014.

Project's operators expect approval from the Energy Department by the end of the year for a loan guarantee to cover 75 to 80% of the estimated $3 billion cost for the first units of the project.

The solar project, once fully operational, is expected to reduce carbon dioxide emissions by almost 1 million tons a year, which is equivalent to removing 1,45,000 cars off the highway.