The First Solar plant, has the apacity to power the equivalent of 60,000 homes, will instead be used to supply electricity for Apple's new campus in Silicon Valley, and its other offices and 52 stores in the state.

Chief Executive Tim Cook said the plant in Monterey County, California will also power an Apple data centre in Newark, California that already relies on solar power.

"We expect to have a very significant savings because we have a fixed price for the renewable energy, and there's quite a difference between that price and the price of brown energy," Cook said.

First Solar, based in Tempe, Arizona, manufactures solar panels and builds solar power plants, many of which it sells to power producers.

Construction of the 2,900-acre California Flats Solar Project is expected to start in mid-2015 and finish by the end of next year, First Solar said in a statement.