Long-duration battery project in the works

Wind farms produce electricity when it’s breezy. Solar panels generate energy during the day. Low-cost, long-duration storage has the potential to serve cooperative members when the wind isn’t blowing and the sun isn’t shining.

A Great River Energy pilot project has the potential to solve the challenges posed by the variable nature of the most common types of renewable energy. As renewable resources supply ever-greater portions of energy on the electric grid, the value of storage resources will rise.

Great River Energy recently announced plans to eliminate coal from its power supply portfolio and add 1,100 megawatts (MWs) of wind energy by 2023. The cooperative has access to abundant energy from the Midwest energy market to ensure electricity remains reliable.

Great River Energy is developing a long-duration energy storage pilot project on a 1-acre site adjacent to its natural gas peaking plant in Cambridge, Minnesota. The Cambridge Energy Storage Project will be a 1 MW, grid-connected storage system capable of delivering its rated power continuously for 150 hours, far longer than the four-hour usage period available from utility-scale lithium-ion batteries today. The battery is expected to be complete by the end of 2023.

“Commercially viable long-duration storage could increase reliability by ensuring that the power generated by renewable energy is available at all hours to serve our membership,” said Jon Brekke, vice president and chief power supply officer at Great River Energy. “Such storage could be particularly important during extreme weather conditions that last several days. Long-duration storage also provides an excellent hedge against volatile energy prices.”

First-of-its-kind technology

Great River Energy is working with Form Energy of Somerville, Massachusetts, on the project. This is the first commercial deployment of Form Energy’s proprietary long-duration energy storage technology.

Form Energy’s aqueous air battery system uses safe, cheap and abundant materials. Form Energy was founded in 2017 and has raised more than $50 million in funding. Investors include MIT and Bill Gates’s Breakthrough Energy Ventures.

Why does long duration matter?

Long-duration storage will help maintain reliability during extreme conditions, such as a heat wave or polar vortex. Low-cost, flexible energy storage solutions can also provide more capability to fill gaps in wind and solar energy production that would otherwise require starting a power plant.