California solar and batteries pushed gas generation lower in 2025

What happened

U.S. Energy Information Administration data show that California's utility-scale solar plants generated 40.3 billion kilowatt-hours from January through August 2025, up 17 percent from the same period in 2024. Natural-gas generation fell 17 percent over that comparison, to 45.5 billion kilowatt-hours. During the 5–9 p.m. window in May and June, average battery output rose from less than 1 gigawatt in 2022 to 4.9 gigawatts in 2025; EIA says the added battery discharge displaced gas generation during those hours.

Why it matters

This is an observed operating-grid result rather than a capacity announcement: daytime solar and evening battery discharge complemented each other while gas generation declined. The comparison is limited to California and part of 2025, however, and hydropower, electricity imports, curtailment, battery losses, and the charging mix all affect the emissions meaning of the generation shift.

What to watch

• Full-year 2025 generation and emissions data, including any revisions to the preliminary monthly figures.
• Whether batteries continue displacing evening gas while renewable curtailment, imports, and round-trip losses remain controlled.
• How rooftop solar, hydropower conditions, transmission, and EIA's changed CAISO gas-data methodology affect longer-term comparisons.

Sources & evidence

• Natural gas use for electricity in California falls as solar generation risesU.S. Energy Information Administration analysis published November 24, 2025, using Electric Power Monthly and CAISO data. The January–August comparison covers utility-scale solar, not rooftop systems, and EIA notes a December 2023 methodology change in CAISO gas-generation data.
• Electric Power MonthlyEIA's underlying monthly electricity-data publication. Values available at the time of the November article were preliminary and may later be revised.

Topics

• California
• Solar Power
• Battery Storage
• Natural Gas
• Grid Operations