Electricity generation from renewables exceeded 93,000 gigawatt-hours (GWh) in 2021—about 3,000 GWh more than the 90,000 GWh in 2018. Although generation from renewables has not significantly increased since 2018, the increase in total RPS percentage is due to the decrease in out-of-state imports of natural gas generation (7,925 GWh in 2021)— 9.1 percent lower than in 2020 and 11.2 percent lower than in 2019—resulting in an overall 45 percent decrease in natural gas generation in Northwest imports (-35.7%) and Southwest imports (-8.9%), compared to 2020. Solar and wind are the largest renewable sources, making up 14.2 percent and 11.4 percent, respectively, of the state’s total power mix(Including Imports).
Electricity generation from biomass, geothermal, and small hydro totaled 22,320 GWh in 2021—the lowest it has been since 2008. So far, solar has dominated renewable generation, accounting for over 80 percent of the state’s increased renewable energy from 2014 to 2021. As the drought persists, small hydro’s share of generation in 2021 (1%) is one of the lowest since the RPS program’s inception in 2002, and it decreased from 2019 to 2020. Moreover, small hydro accounted for 0.36 percent of the total imports of energy sources from other states in 2021, as many other western states are also facing droughts. In general, total hydropower (both large and small, including imports) contributed 28,491 GWh or 10.2 percent to the total power mix in 2021, a 23.1 percent decrease from the 37,073 GWh (or 13.6% of total power mix year) in 2020. The prolonged droughts (now in the third consecutive year) have caused California’s reservoirs to dry up. According to the National Oceanic and Atmospheric Administration (NOAA), 2022 is on track to be the driest year in the 128 years of precipitation recorded in California, due to severe droughts and warmer weather.128 Including hydropower, California now imports 30.1 percent of its electricity supply from neighboring markets, with about 61 percent of that coming from the Southwest and 39 percent from the Northwest.
128 Renewable Portfolio Standard eligible sources include biomass, geothermal, solar, wind, and small hydroelectric facilities.