Energy storage company Form Energy said it signed a contract with utility Great River Energy to jointly deploy a 1MW/150MWh pilot project.

This system will be the first commercial deployment of Form Energy’s proprietary long-duration energy storage system. Form Energy said its aqueous air battery system leverages some of the safest, cheapest, most abundant materials on the planet and offers a clear path to low-cost, long-duration energy storage. Great River Energy is Minnesota’s second-largest electric utility and the fifth largest generation and transmission cooperative in the U.S.

The project with Great River Energy will be a 1-MW, grid-connected storage system capable of delivering its rated power continuously for 150 hours, far longer than the two to four hour usage period common among lithium-ion batteries being deployed at utility-scale today, Form Energy said. This duration allows for a fundamentally new reliability function to be provided to the grid from storage, one historically only available from thermal generation resources, the company said.

“The electrical grid is increasingly supplied by renewable sources of energy. 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. 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,” said Great River Energy Vice President and Chief Power Supply Officer Jon Brekke.

Leading up to the decision to deploy the pilot project, Form Energy conducted a portfolio optimization study of Great River Energy’s unique system characteristics with Formware, a proprietary software analytics platform design to help energy planners model future grids. Formware was purpose-built to model high penetration renewables at the system level and determine how all types of storage enable cost-effective renewable energy integration.

The tool helps planners reduce exposure to extreme weather events and minimize uncertainty around commodity prices under a variety of future grid scenarios.

“Our vision at Form Energy is to unlock the power of renewable energy to transform the grid with our proprietary long-duration storage. This project represents a bold step toward proving that vision of an affordable, renewable future is possible without sacrificing reliability,” said Mateo Jaramillo, CEO of Form Energy.

Great River Energy announced plans to transition its portfolio of power supply resources in the coming years. The electric cooperative plans to phase out its remaining coal resources, add significant renewable energy, and partner with Form Energy on its grid-scale battery technology.

“Long-duration energy storage solutions will play an entirely different role in a clean electricity system than the conventional battery storage systems being deployed at scale today, said Jesse Jenkins, an assistant professor at Princeton University who studies low-carbon energy systems engineering. “Lithium-ion batteries are well suited to fast bursts of energy production, but they run out of energy after just a few hours. A true low-cost, long-duration energy storage solution that can sustain output for days, would fill gaps in wind and solar energy production that would otherwise require firing up a fossil-fueled power plant. A technology like that could make a reliable, affordable 100% renewable electricity system a real possibility.”

Founded in 2017, Form Energy has raised over US$50 million in funding. The company is backed by investors Eni Next LLC, MIT’s The Engine, Breakthrough Energy Ventures, Prelude Ventures, Capricorn Investment Group and Macquarie Capital.