Solar panels produced 51% of California’s electricity during the month of May. This was the first time the clean energy source produced more than half the state’s power for an entire month. But it wasn’t just a milestone for California; it was a milestone for the whole world. California was the first major economy to cross the 50% threshold for an entire month. In June 2025, Hungary produced 47% of its power with solar, but Hungary’s GDP is far smaller than that of California.
The only fossil fuel that California burns at appreciable levels is natural gas and solar is steadily diminishing its use. Solar didn’t just out generate gas in May. It has outproduced it throughout every month of 2026 leading up to it.
The Trump administration keeps saying that the sun doesn’t shine at night, but California’s massive deployment of battery energy storage provides the state with plenty of power at night by shifting midday solar production to the evening hours. It is not unusual for batteries to provide a quarter of the state’s electricity for portions of the night.
Ten years ago, solar power only accounted for 17% of California’s electricity. There were only 61 megawatts of battery storage. Now the California Independent System Operator, which manages the state’s grid, has 16 gigawatts of storage, an increase of over 26,000%.
California will undoubtedly break the 50% threshold again and with increasing frequency and in the coming years, more states and countries are likely to join the club.
**********
References
California was mostly solar-powered in May — a global first
