EIA Report: Large-Scale Battery Storage in US Hits 10-Year High

(Image: Plans for a solar plus storage system that EDF Renewables is designing for Cox Communications in San Diego. Credit: J.Dixx Photography)

The US Energy Information Administration (EIA) released a new report that examines national large-scale battery storage trends over the past decade. Capacity went from seven systems with 59 megawatts in 2010 to 125 systems totaling 869 MW at the end of 2018.

“Battery Storage in the United States: An Update on Market Trends” looks at the state of the market as of 2018, and includes details about applications, cost, ongoing trends as well as market and policy drivers.

“Large-scale battery storage systems are increasingly being used across the power grid in the United States,” according to the EIA. The report found that between 2010 and 2018, the total number of operational battery storage systems more than doubled.

In addition, the report showed that:

• Over 90% of large-scale battery storage power capacity in the United States was provided by batteries based on lithium-ion chemistries.
• About 73% of large-scale battery storage power capacity in the United States, representing 70% of energy capacity, was installed in states covered by independent system operators (ISOs) or regional transmission organizations (RTOs).
• Alaska and Hawaii, with comparatively smaller electrical systems that account for 1% of total grid capacity in the United States, accounted for 12% of the power capacity in 2018, or 14% of large-scale battery energy capacity.
• Historically, the majority of annual battery installations have occurred within the PJM Interconnection (PJM), which manages energy and capacity markets and the transmission grid in 13 eastern and Midwestern states and the District of Columbia, and California Independent System Operator (CAISO) territories. However, in 2018, over 58% (130 MW) of power capacity additions, representing 69% (337 MWh) of energy capacity additions, were installed in states outside of those areas.

The report also explored battery storage costs, which the EIA said are driven by technical characteristics such as a system’s power and energy capacity.

“On a per-unit of power capacity basis, total installed system costs for batteries of shorter duration have been less expensive than long-duration systems,” the report noted. “In terms of costs per-unit of energy capacity, the reverse has been true —longer duration batteries have typically had lower normalized costs compared with shorter-duration batteries.”

Between 2015 and 2017, the average costs per-unit of energy capacity decreased by 61%, the EIA said. In 2015 they were $2,153/kWh, but by 2017 they were down to $834/kWh.