California has installed more than 21 GW of energy storage statewide, making it one of the largest battery fleets in the world, according to the California Energy Commission (CEC). The milestone reflects a broader national acceleration in storage deployment driven by declining battery costs and federal incentives, with Texas also rapidly expanding its storage fleet — though California remains the U.S. leader by a wide margin.

When Governor Gavin Newsom took office in 2019, fewer than 700 MW of battery storage served the grid. The increase to 21,112 MW represents growth of more than 2,500% in approximately seven and a half years. That capacity is equivalent to roughly one-third of statewide peak demand, which exceeded 63,000 MW during the September 2022 heat wave. During that heat wave, battery storage was credited with helping CAISO avoid rolling blackouts during critical evening hours when solar generation dropped off — a role that has only expanded since.

"While Donald Trump is hellbent on burning more expensive fossil fuels and raising costs for Americans, California is proving there's a better way — from new instant rebates putting thousands of dollars back in the pockets of first-time electric car buyers, to an arsenal of batteries across the state that just topped 21,000 MW, the nation's largest, helping power the world's fourth-largest economy," Newsom said. "California is showing the world what real economic security looks like. It's one that can't be held hostage by foreign conflicts and Big Oil. The Golden State is leading the charge on building a reliable, affordable clean future."

Of the total 21,112 MW serving Californians, nearly 16,000 MW comes from 310 utility-scale battery systems located within California. An additional 2,000 MW comes from utility-scale battery facilities in Nevada and Arizona. These resources are part of the California Independent System Operator (CAISO) grid, which serves about 80% of Californians. Another 3,000 MW comes from more than 300,000 smaller battery systems installed at homes, schools, farms, businesses, and industrial facilities across the state. The vast majority of these installations are lithium-ion systems, typically providing two to four hours of discharge duration — enough to bridge the gap between peak solar hours and peak evening demand, but short of the multi-day coverage that emerging long-duration technologies aim to provide.

Solar surpasses natural gas

Energy storage systems that capture solar power reduce the need to rely on gas peaker plants. For the first time, Californians used more solar energy than natural gas during the first half of 2026.

Comparing January through June of 2024 to the same period in 2026, solar power usage grew by 22%, while natural gas usage dropped by 51%, according to the CEC's analysis of state grid data. Over that same period, battery storage capacity on the grid grew by 80%, giving solar power a destination even after sunset. This dynamic directly addresses California's well-documented "duck curve," where abundant midday solar generation creates a surplus that must be curtailed unless storage is available to absorb and shift it to evening hours.

"California has always prioritized innovation, investing in the science and technology of the future and advancing the goalpost on what is possible," said CEC Chair David Hochschild. "Seeing solar surpass gas on the grid is proof that our vision of a 100% clean energy future is absolutely possible."

While seasonal factors play a role — solar production is strong and electricity use is relatively moderate in spring — the trend underscores how the growing contribution of solar and battery storage is reshaping the operation of California's grid.

This shift reflects years of investment in clean energy infrastructure. Since 2019, California has added more than 37,000 MW of clean and renewable energy resources to the grid, leading the nation in deployment of new electricity resources and transforming the state's electric system.

Looking ahead

California estimates that more than 52,000 MW of battery and long-duration energy storage will be needed by 2045 as electricity demand grows from continued electrification of transportation, buildings, and industrial operations. With the current total, California is now 41% of the way toward that goal. Meeting the remainder will likely require commercialization of long-duration storage technologies — such as iron-air, flow, and thermal batteries — that can discharge for 10 hours or more and are currently advancing through pilot and early commercial stages.

Batteries are essential to California achieving 100% clean electricity retail sales by 2045. The latest figures, from the end of 2024, show that 67% of retail electric sales come from clean energy.

This progress is increasingly evident on the CAISO grid. Last year, clean energy resources met 100% of grid demand for at least some portion of the day on 279 days. In the first half of 2026, the CAISO grid reached that mark on 92% of days.

The state is committed to deploying clean energy infrastructure as quickly and safely as possible. The CEC's Opt-In Certification Program, California's accelerated permitting program for clean energy infrastructure, has approved 1,850 MW of battery storage and 1,450 MW of solar generation in the past year, with more than 3,000 MW in the queue and additional projects being added. These projects undergo rigorous environmental and safety review by the CEC and include agreements that provide benefits to the communities where projects are located.