Xcel Energy to build multi-day battery storage project using Form Energy's iron-air batteries

Minnesota-based electric utility, Xcel Energy on Thursday (July 6) announced that it has received approval from the state regulators to build a multi-day battery storage system to help the company maximize the use of renewable energy and maintain grid stability through extreme temperatures and weather.

The demonstration scale, 10MW/1,000MWh iron-air battery system developed by Massachusetts-based Form Energy will be installed near the Sherburne County Generating Station in Becker, Minnesota. The energy storage project will enable Xcel Energy to store the renewable energy generated from solar and wind and distribute it later during periods of lower production.

"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 battery storage project will be located near Sherco Solar – one of the largest solar project in the US currently under development – and will add up to 710 MW of renewable energy to the grid.

According to the company, the Sherco project is one of two battery storage projects to be installed at the sites of retiring Xcel Energy coal plants, with the other location being the Comanche Generating Station in Pueblo, Colorado.

Currently, most of the battery technologies provide fewer than eight-hours of energy storage, however, Form Energy's iron-air batteries can deliver electricity for 100 hours. The multi-day energy storage systems, the company holds, 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.

Earlier in May, Xcel Energy received $20 million grant commitment from Breakthrough Energy Catalyst for using emerging climate technologies to reduce emissions and accelerate the clean energy transition. This grant promises to provide $10 million funding each for the demonstration projects in Minnesota and Colorado and is expected to lower the cost of the iron-air batteries.

To drive down the cost further, Xcel Energy has applied for a grant from the U.S. Department of Energy to reduce the cost of the projects and a decision is expected on the application later this summer. In addition to the grants, the company 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.

The construction of the Minnesota battery storage system will begin in the second quarter of 2024, with the battery expected to come online as early as 2025.