EIA: over 16% of US utility solar added so far in 2026 has storage on site

More than 16% of the utility-scale solar capacity added in the US in 2026 through September is co-located with operable battery storage, up from 2% in 2017, the U.S. Energy Information Administration reported on October 30, 2026, using generator data operators report on its EIA-860 and EIA-860M surveys.

The share could climb from here. Solar additions scheduled for the last three months of 2026 could lift this year's figure to 19%, and operators' plans for 2027 and 2028 put it above 30%. Those are reported plans, not plants.

As of September, 18% of US utility-scale solar capacity is co-located with batteries, EIA says, in a solar fleet that makes up 13% of total US utility-scale generating capacity. By our comparison, this year's projected 19% for new additions roughly matches the installed fleet; the next jump is in the 2027 and 2028 plans. The pairing is regional: in California, Arizona, New Mexico and Nevada, the share of solar generation co-located with battery capacity is more than double the national average, EIA says.

Pairing lets a plant work the price curve, EIA says: wholesale prices in regions with a lot of solar tend to fall when solar output is high and rise as it fades, and a plant with its own battery can send its solar output to the grid or into storage depending on the price, managing the combined output to maximize its value. Batteries and solar at the same plant often enter commercial service at different times; EIA's monthly generator inventory tracks both, which is how it identifies the co-located ones.

The storage side of that build has its own record: US grid batteries stood at nearly 52 GW at the end of June 2026, per EIA's August count.