U.S. Electricity Utilities Expand Battery Use For Arbitrage And Grid Stability

Electricity utilities in the United States are increasingly utilizing batteries for both arbitrage and grid stability, according to recently published data. Arbitrage involves moving electricity from periods of low prices to periods of high prices, making it a strategic approach to manage electricity costs effectively.

As of the end of 2023, U.S. electricity utilities reported operating 575 batteries with a total capacity of 15,814 megawatts (MW). This number is set to grow significantly, with utilities planning to add 35,953 MW of battery capacity by the end of 2028. This information comes from the latest release of data from the EIA-860, Annual Electric Generator Report, which provides detailed insights into battery storage applications, including their use cases, generator configurations, and energy capacity details for planned batteries.

The primary use for these batteries, as reported by utilities, is arbitrage. Out of the total battery capacity, 10,487 MW is primarily used for arbitrage. This process involves charging the batteries by purchasing electricity during low-cost periods and then selling the stored electricity when prices are higher, thereby optimizing cost savings and revenue.

In addition to arbitrage, batteries play a crucial role in enhancing grid reliability through ancillary services. Ancillary services support the transmission of electricity and ensure the stable operation of the power grid. One of the most common ancillary services is frequency regulation, which helps maintain the balance between electricity supply and demand. This service has been reported as a use case for battery capacity frequently.

While many batteries are used for multiple purposes, this recent data release marks the first time utilities have been asked to identify the primary purpose of their batteries. The early release of the EIA-860 data includes this new element, providing a clearer picture of how batteries are being utilized across the energy sector.

Overall, the expanding use of batteries for both arbitrage and grid stability reflects the growing importance of energy storage solutions in the U.S. power market. With the planned increase in battery capacity, utilities are expected to enhance their ability to manage electricity costs and maintain grid stability, contributing to a more efficient and reliable energy system.