California's power grid runs on solar for over half of May electricity

Ember's latest analysis indicates that California achieved a historic level of solar generation in May, with solar accounting for over half of the state's electricity output for the entire month—a global first for a large power system. The surge reflects five years of robust solar growth and a surge in battery storage, which moves excess midday solar to meet evening peaks, according to Ember analyst Nicolas Fulghum. Grid Status analyst Abby Lestina noted that the state's mild temperature profile in May reduced overall demand, allowing solar to dominate the mix.

For the first five months of 2026, solar output exceeded that of natural gas.S. Energy Information Administration, hinting at a possible shift in the state's power composition. Additional imports, such as the SunZia wind project from New Mexico, further lowered reliance on gas-fired generation. While natural-gas usage rose later in the summer as temperatures climbed, the overall trend shows a decline in fossil-fuel electricity and progress toward California's 2045 clean-energy goal.