Analysis
Rusting Iron as a Grid Battery
Ore Energy, an Amsterdam-based startup spun out of Delft University of Technology research, raised a $43 million Series A co-led by Plural and HV Capital, with existing investor Positron Ventures also participating, bringing total funding to $61 million, according to TechFundingNews. The company builds iron-air batteries that store electricity by reversing the rusting process -- charging converts iron oxide back into metallic iron, and discharging re-oxidizes it using oxygen from the air.
“Ore's plan is to build its first manufacturing facility and reach gigawatt-hour-scale production by 2028.”
The pitch is cost and duration, not energy density. Iron-air batteries can store renewable power for up to 100 hours, far longer than lithium-ion's typical four-to-eight-hour window, at roughly a tenth of the cost per unit, per TheNextWeb. That duration profile targets a gap lithium-ion doesn't solve well: multi-day renewable intermittency, exactly the kind of long-duration storage AI data centers need to run on wind and solar rather than gas peaker plants.
The competitive field includes Form Energy, the US iron-air pioneer that has already raised over $800 million and started commercial deployments, which makes Ore Energy a later, better-funded-per-employee entrant rather than a category creator. Ore's plan is to build its first manufacturing facility and reach gigawatt-hour-scale production by 2028.
The counterweight worth noting: Form Energy's multi-year head start on commercial deployment is a real advantage Ore Energy has to close, not just a valuation gap, and $61 million total funding is a fraction of what iron-air's capital-intensive manufacturing scale-up historically requires. What to watch: whether Ore Energy announces a signed offtake agreement with a grid operator or data center developer, the milestone that would separate it from Form Energy's early trajectory rather than just following it.