Factor This

Form Energy’s 100-hour battery is almost here

Form Energy’s 100-hour battery is almost here

Episode 54 of the Factor This! podcast features Form Energy co-founder and CEO Mateo Jaramillo, a former Tesla executive pushing for deep decarbonization on the grid. Subscribe wherever you get your podcasts.

A rendering shows a Form Energy battery system planned near Cambridge, Minnesota. Credit: Form Energy / Courtesy.

It sounded almost too good to be true.

Form Energy quietly launched in 2017 as a startup with big ambitions. The company aimed to manufacture and deploy an iron-air battery capable of delivering days of clean power on demand.

The firm was targeting a problem that didn't yet exist, but would become more pronounced as intermittent renewable energy resources displaced fossil fuel assets on the grid. Lithium-ion batteries could fill some of the gap as solar and wind output rose and fell, but only for minutes or a handful of hours. A multi-day, grid-scale energy storage solution would be critical for deep decarbonization, Form Energy's founders posited, even though previous efforts failed to fully capitalize on the opportunity.

Slick project renderings and the promise of a 100-hour storage solution allowed the company to raise nearly $1 billion, which included support from the likes of Bill Gates. Form Energy claimed its iron-air battery could be deployed at system costs that would be competitive with conventional power plants and at less than 1/10th the cost of lithium-ion.

Little was known, or shared, about how the battery might perform in the field. As is true for many emerging technologies, the company's marketing promises were met with some skepticism.

But six years after its launch, Form Energy says it is ready to prove its technology in primetime. The company has signed deals to deploy its battery with such risk-averse utilities as Xcel Energy, Southern Company, and Great River Energy, and recently broke ground on a commercial-scale battery plant in West Virginia.

Form Energy's CEO, Mateo Jaramillo, is quick to dismiss the string of milestones as successes. The former Tesla battery executive acknowledges that the company has yet to put steel in the ground. But the momentum behind a critical technology advancement can't be understated, either.

"I've been in batteries now for almost 20 years, and it is particularly gratifying to see a lot of real activity happening," Jaramillo said on the Factor This! podcast from Renewable Energy World. "I don't love the term hype, but there's a lot of talking. And until we actually produce that, then we can't say that we've gotten to where we want to be despite the long path that we have come down."

How it works

Form Energy didn't invent the iron-air battery chemistry, which dates back more than a half-century. The U.S. Department of Energy commissioned a study by Westinghouse in the 1970s to explore iron-air battery applications for transportation, but those didn't end up being ideal use cases.

At a high level, the basic principle of Form Energy’s battery operation is reversible rusting.  The battery contains an iron anode, resembling an automobile’s brake pad, and an air-breathing cathode. They are submersed in an electrolyte water bath with a permeable separation between them. When the iron is exposed to the oxygen and air, it triggers a chemical process called oxidation – otherwise known as rusting. That oxidation process releases electrons that are separated and sent to the grid – providing electricity when demand exceeds supply.  When there is excess power on the grid, the process is reversed and electrons flow in, releasing the oxygen and causing the iron to unrust, taking it back to a metallic state.

But Form Energy doesn't see itself only as a battery manufacturer. They implement systems, Jaramillo said, not chemistries.

"Nobody actually wants to buy a battery. What they want is electricity when they need it. That means, all they care about is the high side of the medium voltage," Jaramillo said. "If we're only focused on the electrochemical reaction and we get everything from the cell DC voltage wrong, all the way up to the medium voltage, it doesn't matter."

Form Energy's iron-air battery. (Courtesy: Form Energy)

Timing is everything

Much of Form Energy's progress to date can be attributed to timing. Other well-intentioned and capable companies have taken on the multi-day storage challenge only to be too early for the market, Jaramillo said.

Even so, the market for its technology is still emerging. Form has spent years talking with policymakers and utilities about the merits of multi-day storage, which isn't adequately compensated by wholesale electricity markets.

Regulated utilities do, however, understand pricing for reliability, and have the ability to factor it into internal planning processes. One-hundred hours of energy storage also is familiar from pumped hydro, which represents the vast majority of nameplate rated storage on the grid.

"(Timing) was a fear that we had, of course, that it would be too early," Jaramillo said. "In conversations dating back in 2021, when it started to be very evident that that this could play a pretty prominent and impactful role, (utilities) want it right then.

"There's no in between. It was too early and then--now--not fast enough."

The real deal(s)

That sudden shift to go-go led to a deal with Xcel Energy for a demonstration-scale, 10 MW/1,000 MWh project be installed 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.

Michael Webber, an energy researcher and professor at the University of Texas at Austin, and the chief technology officer at Energy Impact Partners, one of Form Energy's investors, said "utilities are clamoring for a solution" that addresses prolonged windless or cloudy days without relying on fossil fuels.

"This," he said, "just might be it."