The Oakland solar power company BrightSource Energy Inc. has just signed a contract with PG&E to build three solar power plants in the Mojave desert. According to the Chron, Brightsource will use mirrors to concentrate sunlight, which the firm will use to generate enough steam to power 375,000 homes in the Bay Area. But before you start getting warm fuzzy thoughts about what a wonderful, progressive company PG&E is, remember: it’s the law. The state legislature has mandated that twenty percent of PG&E’s power come from renewable sources. So score one for the eco-tyrants!