U.S. Sees Rapid Growth In Utility-Scale Battery Energy Storage, Surpassing 20.7 GW In Capacity

Battery energy storage systems are rapidly expanding as a key component of the U.S. electric power grid. In the first seven months of 2024, the U.S. saw an addition of 5 gigawatts (GW) of utility-scale battery energy storage capacity, according to data from the July 2024 electric generator inventory. This represents a significant increase from 2010, when only 4 megawatts (MW) of such capacity were added. As of July 2024, the total battery energy storage capacity in the U.S. has surpassed 20.7 GW.

These systems play a crucial role in supporting the electric power grid by providing various services. They help balance supply and demand, facilitate electricity price arbitrage by moving power from low-price periods to high-price periods, and enable the storage of renewable energy, such as wind and solar power, for use when needed instead of curtailing these sources when their output exceeds consumption.

Unlike primary electricity sources, battery storage systems do not generate electricity but store it from existing generators or the grid, making them secondary sources of electricity. These systems generally consume more electricity for charging than they deliver to the grid. Despite this, they are included in the Annual Electric Generator Report and monthly electric generator inventory data due to their role in providing capacity to meet demand.

Most utility-scale battery energy storage systems in the U.S. use lithium-ion batteries. Small-scale batteries, defined as having less than 1 MW of power capacity, are reported separately from utility-scale systems. Other energy storage technologies include pumped-storage hydroelectricity, flywheels, and compressed air. Detailed information about how these storage systems work can be found on the Energy Explained page dedicated to energy storage for electricity generation.