California electric power production at least is very “green” as far as CO2 goes. There are no coal fired power plants in California. All in-state electric power is either nuclear, hydro or natural gas with some VERY minor wind and geothermal.
Some electricity is imported from Arizona that has a coal plant, and is rather hypocritically imported by the Los Angeles Department of Water and Power, aka the largest California public agency in the generation business and ostensibly the “greenest”.
California production of Nat Gas however will reduce out of state imports and so will have an effect, probably, in displacing other sorts of power plant fuels, but elsewhere.