SAN FRANCISCO — Solar deals heated up this week, as Apple Inc. and the nation's largest electric utility signed separate deals for solar energy installation and production in California.

On Tuesday, Apple announced it had signed a 25-year power-purchase agreement with First Solar Inc. In exchange for an investment of $848 million, Apple will receive electricity from 130 megawatts of First Solar's California Flats project in Monterey. The solar panel field is set to start construction this year and be completed by the end of 2016. Apple's data centers are currently powered with renewable energy.

Apple did not respond to email messages seeking details on the deal team. First Solar, based in Tempe, Ariz., used both in-house and outside counsel, relying on assistant general counsel Beth Deane and Winston & Strawn associate Thomas Solomon.