Commodities
California Gas-Fired Power Use Falls to Record Low as Batteries, Renewables Gain Ground, WoodMac Says
Natural gas supplied just 3.1% of electricity generation in the California Independent System Operator market on May 16, marking a record low, Wood Mackenzie said Thursday.Gas accounted for less than 10% of daily CAISO generation from May 13 through May 17 as California continued reducing its dependence on gas-fired power, according to Wood Mackenzie.Gas never supplied less than 20% of CAISO generation during the first 135 days of 2021 and exceeded 40% on 99 days, while the number of days above 40% fell to 56 in 2025.Through May 15 this year, gas accounted for less than 20% of CAISO generation on 68 days and did not exceed 50% on a single day, Wood Mackenzie said.California consumed an average of 35.7 billion cubic feet of gas per month during the 12 months ended March, down 34% from March 2023 levels and less than half the record 76.7 Bcf reached in December 2001.Installed battery storage capacity across CAISO increased to 16,251 megawatts in April 2026 from 1,500 megawatts reported in August 2021, according to CAISO data cited by Wood Mackenzie.Battery storage now regularly supplies at least 20% of system demand during evening hours by shifting solar generation produced earlier in the day.On May 16, battery systems supplied at least 20% of demand between 7:05 p.m. and 11:10 p.m., while gas-fired generation did not exceed 3% of demand during that period, Wood Mackenzie said.Battery output exceeded 7,500 megawatts and averaged up to 3,600 MW over the previous 31 days, reducing the need for gas-fired generation before sunrise.Gas-fired generation totaled just 12,477 megawatt-hours on May 16, compared with the lowest daily totals of 104,174 MWh in 2021 and 50,199 MWh in 2025.The 3,650-megawatt SunZia project began delivering wind power into the CAISO market in early May, with CAISO securing 3,167 MW of capacity and currently holding 2,131 MW of transmission rights.Wind generation reached a record 8,294 MW on May 15 and averaged about 7,000 MW overnight on May 16, compared with roughly 4,000 MW a year earlier, according to Wood Mackenzie.CAISO is developing two transmission projects that could add up to 5,000 MW of new capacity, including the 2,000-MW Southwest Intertie Project scheduled for 2028 and the TransWest Express line expected to begin operating in 2031, Wood Mackenzie said.The 732-mile TransWest Express project will transport wind power from Wyoming into California, supporting further growth in renewable generation across the CAISO system, according to Wood Mackenzie.Utility-scale solar capacity in CAISO increased to 22,702 MW in April 2026 from 14,116 MW in 2021, providing additional support for battery storage and renewable generation, Wood Mackenzie said.Solar generation totaled 16.6 million MWh through May 12, up 48% from 2021, while its share of CAISO generation reached 33.2%. Over the same period, gas-fired output fell 53% to 10.9 million MWh, and its market share declined to 21.8%.The Energy Information Administration expects solar generation to exceed gas-fired generation in California for the first time this year, with the gap widening further in 2027, Wood Mackenzie added.Investments in solar, battery storage and transmission infrastructure over the past five years have sharply reduced California's reliance on natural gas, bringing the state's long-term goal of moving away from fossil fuels closer to reality, Wood Mackenzie said.
