- Solar-energy-generated electricity supplied 3,796 megawatts, about 10%, of California’s 41,549 megawatt May 15 peak demand in the middle of California’s first summer heat wave. Wind supplied some 1,876 megawatts of the May 15 demand.
- Drought-driven hydro shortages, coal plant retirements, and the forced closure of the 2,200 megawatt San Onofre Nuclear Generating Station continue to make for concerns about the state grid’s ability to meet peaks in demand.
The California Independent System Operator (CAISO) continues to express confidence that the steps it has taken will meet demand but has repeatedly told this reporter it is prepared to call for demand response measures and for conservation from ratepayers during peak periods.
Overall, 60.8% of California’s electricity is sourced from natural gas, 22% is from renewables, 12.5% comes from large hydro (which does not count toward the state renewables mandate), 3.5% is from nuclear, and small amounts come from coal and oil.
As of April 22, CAISO had a total renewable generation capacity of 14,330 megawatts, of which 41.5% was wind, 31.1% was solar, 11.0% was geothermal, 8.9% was small hydro, 4.8% was biomass, and 2.9% was biogas.