But now state officials may extend the life of several facilities that still suck billions of gallons from the ocean each day. But many clean energy advocates argue California should get off gas entirely — partly because of the carbon emissions generated by burning gas, and partly because gas plants also emit local air pollution, often in disadvantaged communities that have long suffered from hazardous air quality. As of , California’s crude oil output accounted for about 8. Non-hydroelectric renewable technologies, such as solar, wind, geothermal, and biomass, provided more than one-fourth of the state’s net generation in About Us. However, by , hydropower’s share rebounded with increased precipitation, and hydroelectric power plants provided one-fifth of the state’s net generation.