US battery storage boom extends into 2025; nearly 19 GW under construction

US developers of large-scale battery storage stations have 18.7 GW of new capacity under construction, according to S&P Global Commodity Insights Market Intelligence data, indicating another strong year for the grid's electrochemical shock absorbers.

Capacity under construction has grown by a net 4.5 GW since late November 2024 despite project completions in recent months. Developers broke ground at an accelerated pace, exempting projects under existing federal tax incentives that could be repealed or amended by the Republican-controlled Congress.

If schedules remain on track, capacity under construction would put the industry on pace to exceed the record of about 11 GW completed last year, Market Intelligence data shows. This would continue the ascent of a technology that emerged in 2024 as the second-largest resource added to the US grid.

The US Energy Information Administration expects 18.2 GW of utility-scale battery storage resources to come online this year, or 29% of anticipated capacity additions, second only to solar with 32.5 GW of anticipated new capacity.

The under-construction assets are part of a broader pipeline of projects at various stages of development, totaling over 150 GW of planned capacity additions through 2030, according to Market Intelligence data. This compares with almost 30 GW of nonhydroelectric energy storage online as of the end of 2024.

Although developers plan to add more than 38 GW in each of the next three years, they started out with ambitions for 34 GW of new capacity in 2024 — of which less than a third came online last year. Developers slowed their commissioning pace to finish 2024, completing 3,209 MW of battery power storage capacity in the fourth quarter, down 9.2% from a year ago and about 13% lower quarter over quarter, Market Intelligence data shows.

Battery peakers proliferate

Most big battery stations online and under construction are lithium-ion systems designed to discharge up to four hours of energy storage. They are frequently installed together with solar farms, effectively creating zero-emission peaker plant alternatives to natural gas.

Among the biggest new battery peakers that entered operations in 2024 were Calpine Corp.'s Nova Power Bank Project in Riverside County, California. Of this, 620 MW/2,480 MWh came online last year, and another 60 MW/240 MWh is under construction.

Others included the 380-MW/1,416-MWh Gemini Battery Storage Project, operating with the 690-MW Gemini Solar Project outside Las Vegas, and the 300-MW/1,200-MWh Atrisco Battery Storage Project in Bernalillo County, New Mexico, as part of the 360-MW Atrisco Solar Project.

Arevon Energy Inc. energized the first phase of its more than $2 billion Eland solar-plus-storage power plant in Kern County, California, in 2024, including 300 MW/1,200 MWh of storage. A second phase is under construction.

"There are literally thousands and thousands of projects in various stages of development," Arevon CEO Kevin Smith said in a recent interview.

Approximately four dozen battery projects or major phases sized 100 MW or larger came online across the US in 2024. Of the total 11,093 MW completed last year, 6,749 MW was at stand-alone sites, while 4,434 MW was colocated with other power plants, mostly solar, according to Market Intelligence data.

More than 80 battery peakers with power storage capacities of at least 100 MW are under construction, the largest of which is AES Corp.'s 700-MW Rexford 1 Battery Storage Project, arising together with a solar facility in Tulare County, California.

Projects completed, under construction and in the deeper development pipeline remain heavily weighted toward California, the Desert Southwest and Texas, with significant additional clusters in the Northeast and Northwest.

California leads with over 12 GW in operation, according to Market Intelligence data compiled Feb. 20, followed by Texas with almost 8.8 GW in operation, Arizona with over 2 GW and Nevada with about 1.4 GW.

But Texas has 64.3 GW of planned storage additions, almost twice as much as California at about 33 GW. Another 17.5 GW is planned in Nevada, along with 12.7 GW in Arizona, 4.9 GW in Oregon, 3.3 GW in New York and 2.5 GW in Indiana.