Southern California Edison, a utility arm of Edison International, said on Wednesday it had signed contracts to buy up to 960 megawatts of power from solar thermal and wind power suppliers.

The contracts are part of California's aggressive push to require utilities to add more renewable energy sources and reduce the state's dependence on fossil fuels that are blamed for contributing to climate change.

SCE's new agreements include two contracts with Germany's Solar Millennium AG for up to 726 MW of electricity from solar thermal plants that are scheduled to begin operations in 2013 and 2014, the company said in a release.

Other contracts include a deal with BP unit BP Wind Energy and Ridgeline Energy LLC for 90 MW of wind power in Southeast Idaho and another with Columbia Energy Partners for 40 MW of wind power in Central Oregon. Both projects are expandable, the utility said.

Financial details of the contracts were not released.

Solar Millennium's solar thermal plants will be located in Blythe, in Southern California, and in Ridgecrest, which is in the middle of the state. One of those projects could be expanded by an additional 242 MW, the utility said.

In February, SCE announced it had signed contracts with Brightsource Energy to buy 1,300 megawatts of electricity from new solar thermal plants.

Solar thermal power plants use the sun's heat to create steam that powers an electricity-producing turbine. The thermal plants are typically much larger than plants made up of photovoltaic solar panels, which turn sunlight into electricity.

Solar Millennium in March announced a joint project with NV Energy to build a 250 MW solar thermal plant near Las Vegas that will open in 2013 or 2014. That project is expected to cost about $1 billion.

NV Energy is the holding company for Nevada Power Co and Sierra Pacific Power Co, the two major electric utilities in Nevada that together deliver power to about 2.4 million homes and businesses.

Worldwide, Solar Millennium has about 2,000 MW of solar thermal projects either installed or in development, mainly in Spain, the United States, China and northern Africa.

Millennium in November 2008 opened Europe's first solar thermal power plant, Andasol 1 in Spain, which was later sold to a fund that invests in solar power.

(Reporting by Matt Daily, Nichola Groom and Bernie Woodall, editing by Leslie Gevirtz)

(Reporting by Nichola Groom)