The US battery storage market just posted its biggest quarter ever, adding 20.2 gigawatt-hours (GWh) of new capacity in Q2 2026.
The record quarter brought total battery storage installations for the first half of 2026 to 30.8 GWh – up 23% year over year – according to the new “US Energy Storage Market Outlook” from the Solar Energy Industries Association (SEIA) and Benchmark Mineral Intelligence.
Nearly all the growth came from large grid batteries. Utility-scale projects accounted for about 18 GWh of Q2 installations, supported by seven gigawatt-hour-scale projects – four in Arizona, two in California, and one in Utah.
Arizona alone added a record 6.2 GWh, the strongest quarter ever recorded by a single state. Texas added 3.8 GWh, and California installed another 3.6 GWh. Of the utility-scale capacity installed during the quarter, 44% was paired with solar, while 56% was standalone storage.
