In a filing Monday with the Virginia State Corporation Commission (SCC), Dominion Energy Virginia proposed a groundbreaking battery storage pilot project that the company says could significantly increase the length of time batteries can discharge electricity to the grid.

The Darbytown Storage Pilot Project will test two new technologies as potential alternatives to traditional lithium-ion batteries, both of which could offer strengthened safety features for battery storage.

One of the technologies could discharge energy for multiple days. The batteries in the company’s fleet and across the U.S. have durations that, on average, are limited to four hours or less.

The proposed project comes at a critical time as the company develops the largest offshore wind project in the U.S. and continues expanding the second-largest solar fleet in the nation.

“We are making the grid increasingly clean in Virginia with historic investments in offshore wind and solar,” said Ed Baine, President of Dominion Energy Virginia. “With longer-duration batteries in the mix, this project could be a transformational step forward, helping us safely discharge stored energy when it is needed most by our customers.”

The pilot project, which will be located at the existing Darbytown Power Station in Henrico County, will test two alternatives to lithium-ion batteries: iron-air batteries developed by Form Energy and zinc-hybrid batteries developed by Eos Energy Enterprises.

Form Energy’s iron-air technology has the potential to discharge energy for up to 100 hours, significantly longer than the batteries available on the market today.

“We are pleased to partner with Dominion Energy on the innovative Darbytown Storage Pilot Project and look forward to delivering a 100-hour iron-air battery system that will enhance grid reliability and provide Dominion’s Virginia customers with access to wind and solar energy when and where it is needed over periods of multiple days,” Form Energy’s co-founder and CEO Mateo Jaramillo said.

In addition to SCC approval, the project would require development plan approval from Henrico County. If approved, construction would begin by late 2024, and the project would be operational by late 2026.

The project would add to Dominion Energy Virginia’s growing fleet of battery storage facilities, including three in operation in Powhatan, New Kent, and Hanover counties. The company has three additional large-scale battery storage facilities under development in Chesterfield County, Sussex County, and Dulles International Airport in Loudoun County.

Groundbreaking for Form Energy’s iron-air battery manufacturing facility.Pictured left to right: Secretary Mitch Carmichael, West Virginia Department of Economic Development Secretary; Mateo Jaramillo, CEO and Co-Founder of Form Energy; Secretary Jennifer Granholm, U.S. Department of Energy Secretary; Senator Joe Manchin, (D-WV); Dot Gilliam, Equipment Maintenance Technician, Form Energy; Ted Wiley, President & COO of Form Energy. Credit: Form Energy

Form Energy has secured several deals with utilities to demonstrate its technology.

Xcel Energy is deploying a 10 MW/1,000 MWh Form Energy battery on 5 acres of land near the Sherburne County Generating Station in Becker, Minnesota. The project was recently approved by the Minnesota Public Utilities Commission.

Southern Company subsidiary Georgia Power, meanwhile, plans to deploy a 15 MW/1,500 MWh Form Energy system as early as 2026, pending regulatory approval. And Great River Energy, Minnesota’s second-largest electric utility, aims to partner with Form Energy on a 1.5 MW/150 MWh system.

In May, Form Energy started construction of its first iron-air battery manufacturing facility in Weirton, West Virginia. When fully operational in mid- to late-2024, Form Factory 1 is expected to have an annual production capacity of 500 MW of iron-air batteries.

Eos Energy recently announced a $500 million manufacturing expansion plan that includes a $398.6 million conditional loan commitment from the Department of Energy’s Loan Programs Office.

The Eos Z3 battery contains predominately American components and is specifically designed for mass production and meeting low-cost, long-duration, grid-scale stationary energy storage needs, the company said.