We reported yesterday that based on preliminary figures from the California Independent System Operator (CaISO), which operates the state's transmission grid, it looked as though California had more than 1,000 megawatts of solar power flowing into the state's grid mid-day Monday. Today, CaISO released data that confirmed that assessment. California's peak solar output reached 1,029 megawatts on Monday, August 20, a new record for the state -- and one sure to be broken as more solar capacity comes online.
As we mentioned yesterday, peak output is only one aspect of ranking solar's importance in the power portfolio. Solar's overall contribution to the grid yesterday amounted to 9,117 megawatt-hours, just 10% of the state's total renewable power output (which was 85,546 megawatt-hours) and just a hair above 1% of the state's total power demand for the day, 820,135 megawatt-hours.
Though solar came in second among renewables yesterday in terms of peak power -- wind turbines' contribution peaked at 2,617 megawatts -- solar remained in the #3 spot when ranked in total megawatt-hours of power generated. Geothermal energy, which peaked at 919 megawatts, nonetheless provided 20,893 megawatt-hours of power to the state, more than twice solar's contribution.
California's total renewable energy output, including small hydroelectric, biogas and biomass, peaked at 4,379 megawatts yesterday at around 10 p.m.