U.S. Energy Storage Market Posts Record 18.9 GWh in Q2 as Longer-Duration Systems Drive Growth

In the second quarter of 2026, the United States witnessed a record installation of 18.9 GWh of battery energy storage systems, according to a report by the American Clean Power Association and Wood Mackenzie. The growth in energy market share increased by 17% year-over-year, despite a 7% overall decline in installed power capacity.

The average duration of installed battery energy storage systems rose from 2.8 hours to 3.5 hours, driven by utility-scale deployments of 4.7 GW/17.6 GWh. However, the total megawatt installations decreased by 8% year-over-year, as key markets reached saturation. Despite this, installations were up 5% year-over-year in the first half of 2026, indicating that 2026 installations will remain consistent with last year's output.

The Community, Commercial, and Industrial (CCI) sector saw a return to historical deployment levels, installing 48 MW in Q2, driven by a long-duration project in California and utility-contracted storage assets deployed in Texas. The residential sector recorded its fourth-largest quarter on record, with 676 MW installed, marking a 15% quarter-over-quarter decline but a 3% year-over-year increase.

Overall, the residential storage market is projected to contract by 4% in 2026 due to tax credit elimination, consumer hesitancy, and challenges in third-party-ownership. However, the top five U.S. markets, including California, Texas, Puerto Rico, Arizona, and Illinois, accounted for 88% of residential storage capacity installed in Q2, with Puerto Rico experiencing the most significant decline in absolute terms.

With a strong pipeline and ongoing technological advancements, storage systems are crucial for meeting rising electricity demand and ensuring grid reliability. According to industry experts, the U.S. energy storage market is expected to grow over 50% in megawatt terms over the next five years, reaching 207 GW and 715 GWh cumulative installed capacity by 2031.