The US installed 57.6 GWh of battery energy storage in 2025, up 52% year-over-year and the largest single-year total on record, per SEIA and Wood Mackenzie full-year data released February 2026. Solar-plus-storage hybrid projects were the primary driver, as utility-scale solar developers increasingly pair storage to meet grid operators’ dispatchability requirements and capture the combined ITC stack available under the IRA.
The largest single approved project in 2025: the Darden project in Fresno County, California, permitted by the California Energy Commission in June. At 1,150 MW of solar paired with 4,600 MWh of battery storage, it is the largest solar-plus-storage project approved anywhere in the world. The project generates enough electricity to power approximately 850,000 homes for four hours.
The storage record matters for the lithium demand frame separately from the solar story. 57.6 GWh of deployed storage in one year is a direct draw on battery supply chains: cells, cathode material, electrolyte, and pack assembly. Analyst forecasts for 2026 put the next installation milestone at roughly 80-90 GWh, with the ERCOT and CAISO markets driving the bulk of deployment. The 52% year-over-year growth rate, held over multiple years, is the underlying demand curve that the lithium rebalance thesis is tracking.