Gov. Jerry Brown is expected on Wednesday to sign an ambitious climate change measure to increase California's renewable electricity use to 50 percent and double energy efficiency in existing buildings by 2030. The governor and Democratic legislative leaders wanted to include a provision in the current bill to cut petroleum use by half, but they met fierce opposition from the oil lobby. The final bill Brown is considering Wednesday defers to state regulators to implement the programs to increase renewable electricity use and double energy efficiency in existing buildings.