Form Energy brings in more cash as it prepares for mass battery deployment

Rapid load growth and interconnection backlogs across the U.S. are creating acute challenges for utilities. But they’re also opening up new markets for companies with creative technology solutions. 

One company in particular looks poised to benefit: Form Energy.

Form, which makes iron-air batteries out of an old steel factory in West Virginia, just closed a $405 million Series F venture round. The round, led by T. Rowe Price, brings Form’s fundraising total to more than $1.2 billion. 

The fundraise marks a new phase for the long-duration energy storage company: commercial scale.

“The capital in this raise will enable us to get to full commercial production,” said Gabriel Kra, managing director and co-founder of Prelude Ventures, which participated in the round. (Editor’s note: Prelude is also an investor in Latitude Media.) 

Form started construction of its West Virginia factory in 2023. It turned on the production line last month “on time and on budget,” said Kra.

“Building a first-of-a-kind factory for such a huge system – which is 10s of megawatts and hundreds of megawatt-hours – is very complicated. The build-out has exceeded my expectations,” he said.

The next big milestone: proving the commercial-scale batteries work as advertised. 

Form’s long-duration batteries store and discharge electricity by rusting and unrusting iron. The company has more than 13 gigawatt-hours of projects that will come online in 2025 and 2026. The projects range from 100 megawatt-hours to 8,500 megawatt-hours. 

Customers and partners include: Great River Energy, Xcel Energy, Dominion Energy, Georgia Power, the New York State Research and Development Authority, the California Energy Commission, and the Department of Energy.

“The next proof point is actually shipping them off the line and having them meet product specifications and customer expectations. That’s a huge challenge for any company, but my expectation is that by the end of 2025 we will have delivered tens of megawatts of batteries and will be poised for dramatic growth in 2026. It won’t be easy, but that is our expectation,” said Kra.

The Series F comes as customer demand for Form’s technology grows. The company’s 100-hour battery targets multi-day storage applications that can bolster the grid during extreme weather events, balance large swings in renewable generation, and displace high-capacity fossil fuel generation.

Mateo Jaramillo, CEO of Form, said on an episode of the Catalyst podcast that the batteries are bringing both capacity and reliability to the grid. 

“The reason why [100 hours], four days roughly, becomes relevant is because that's where a lot of the material weather events sit in terms of duration,” he told host Shayle Kann. “And in a grid that increasingly is driven by weather, renewable energy, you need to be able to account for that type of intermittency that does inevitably come along.”

New load growth — from electrification, onshoring of manufacturing, and data centers — has forced utilities to re-evaluate their resource planning. Some, like NextEra, are investing in new renewables, while others are planning for more natural gas. Meanwhile, requests for interconnection are piling up for renewable energy projects. 

According to Kra, storage will be a key piece of this response to load growth: “This is the least-cost way to meet the energy and capacity requirements as demand increases,” he said. 

T. Rowe Price and GE Vernova led the round. All existing investors participated in the round as well, including Prelude, TPG Rise Climate, Breakthrough Energy Ventures, Energy Impact Partners, and MIT’s The Engine Ventures.

More details about the raise will be released in the coming days, according to Kra. 

“The success of the raise was an attractive valuation for Form. It was an increase in valuation from our prior raise,” said Kra. “And it’s a testament for the need for the product, the customer demand, and the execution of the company.”