Xcel Energy received approval from state regulators to construct a multi-day energy storage system that will help maximize the company’s use of renewable energy and maintain grid reliability through extreme temperatures and weather.
The demonstration-scale, 10 megawatt/1,000 megawatt-hour iron-air battery system, developed by Massachusetts-based Form Energy, will be installed on 5 acres of land near the Sherburne County Generating Station in Becker, Minnesota. The project will be located near one of the largest solar developments in the U.S., Sherco Solar, which is now in development and will add up to 710 megawatts of renewable energy to the grid.
Construction of the battery system will start in the second quarter of 2024, with the battery expected to come online as early as 2025. The project is expected to support 15 to 20 construction jobs and generate $9 million in local tax revenue.
“Multi-day battery storage has the potential to help us better harness the renewable energy we generate while ensuring the grid remains reliable for our customers,” said Bria Shea, regional vice president, regulatory policy for Xcel Energy–Minnesota. “We look forward to bringing this system online at our Sherco site and learning more about the role it can play in our larger effort to reach 100% carbon-free electricity.”
The project is one of two battery storage projects to be installed at the sites of retiring Xcel Energy coal plants, with the other location at the Comanche Generating Station in Pueblo, Colorado. The batteries will allow Xcel Energy to store renewable energy such as solar and wind when it is being produced and then later distribute the energy during periods of lower production.
While most existing battery technologies provide fewer than eight hours of energy storage, Form Energy’s iron-air batteries could deliver electricity for 100 hours. The multi-day energy storage systems will strengthen the grid against normal day-to-day, week-to-week, and season-to-season weather variability, as well as to extreme weather events such as severe winter storms and polar vortex events.
In April, the iron-air battery projects received a $20 million contingent grant commitment for its efforts in using emerging climate technologies to reduce emissions and accelerate the clean energy transition. The grant provides $10 million each for the Minnesota and Colorado battery systems, subject to the satisfaction of certain funding conditions.
Xcel Energy has also applied for a grant from the U.S. Department of Energy to reduce the cost of the projects. The company expects a decision on the application later this summer.
In addition to grant funding, Xcel Energy plans to use provisions in the federal Inflation Reduction Act, such as renewable energy tax credits, to further lower the cost of the iron-air batteries.