Despite ongoing supply chain issues, US developers plan to install 25GW of utility non-hydroelectric energy storage capacity through 2023, almost five times the 5.4GW in commercial operation nationwide at the end of last year, according to new figures from S&P Global Market Intelligence.

The research house expects 9.4GW of energy storage capacity to come online this year and a further 15.6GW in 2023 ,with nearly 60% to be co-located with other – chiefly solar – power plants.

Developers added 1.33GW of energy storage capacity in the fourth quarter of 2021, exceeding the previous two years combined, and energised more than 3GW last year.

That surge pushed cumulative installed nonhydroelectric storage capacity to 5.41GW entering 2022 and “marked the start of a multi-gigawatt annual market,” wrote S&P market report author Garrett Hering.

While developers fell well short of the more than 5GW of intended projects in 2021, “the still-robust expansion highlights the rise of electromechanical energy storage as a major resource for US utilities and independent grid operators seeking to manage the variability of wind and solar energy and find alternatives to natural gas-peakers,” said Hering.

California and Texas are expected to remain at the heart of the US utility energy storage market for the foreseeable future. On 1 January, the two states had nearly 3GW of total US power storage capacity and 20GW of the 25GW expected to be online through 2023, according to S&P.

These numbers do not reflect the deeper project development pipelines under study California Independent System Operator (Caiso) and Electric Reliability Council of Texas (Ercot), which manage the main bulk electricity grids and markets in those states.

Substantial power storage development is also underway in other southwestern states, especially in Nevada, as well as Hawaii, Massachusetts, and New York.

The great majority of projects completed in 2021 were lithium-ion battery systems with two to four hours of energy storage capacity.

Four hours is rapidly becoming the industry standard and projects with greater energy storage duration will become more prevalent as technology evolves over the next several years, John Hensley, vice president of research and analytics at industry body American Clean Power Association, told Recharge recently.

Clean energy advocates and industry players are lobbying Congress to approve federal tax credits for standalone non-hydroelectric storage, a move they say would turbocharge sector development at scale and help provide the foundation necessary for the US power sector to become 80% carbon-free by 2030.