Form Energy, the American startup behind the iron-air battery, has announced its first project outside the United States: a 10MW/1,000MWh installation in Ireland, planned with developer FuturEnergy Ireland and anticipated to come online in 2029.
The company, led by a former Tesla Energy executive, is commercialising an iron-air battery built to discharge at full rated power for roughly 100 hours. The chemistry is deliberately plain: the cell works through the reversible oxidation of iron, breathing in oxygen and rusting as it discharges, then un-rusting under an electric current as it charges. Where lithium-ion systems cover a few hours, the design is aimed squarely at multi-day gaps in wind and sun.
Industry outlet Energy-Storage.News, which reported the 18 March announcement, carried an enthusiastic verdict from FuturEnergy Ireland CEO Peter Lynch. “Form Energy’s battery solution is set to fill a critical gap in Ireland’s power system. Their pioneering 100-hour, iron-air battery technology will provide a first opportunity to deliver large volumes of clean power across multiple days, and in doing so provide a boost to Ireland’s energy goals,” Lynch said, adding: “The technology is modular, scalable and locationally flexible, enabling it to simultaneously solve local grid congestion and the linked issue of wasted renewable power.”
The timing suits Ireland’s policy machinery. The government’s Electricity Storage Policy Framework, published in 2024 and described by ministers as a first of its kind, identified long-duration storage as central to the country’s energy and emissions targets. Renewables covered roughly half of Irish electricity demand in December 2025, yet the grid operator EirGrid has struggled to integrate that wind-heavy supply, paying for costly curtailment when generation outstrips demand.
The deal had a ceremonial seal as well: Foreign Affairs and Defence Minister Helen McEntee attended a signing on 17 March, St Patrick’s Day, at Form Energy’s Massachusetts headquarters. The partnership “will help boost and expand Ireland’s clean energy usage”, McEntee said, arguing that “Ireland and the United States need to be able to work together to take on today’s challenges, meeting the needs of affordable energy with new technologies.”
For now the project is a demonstration, sized to prove that clean power can be delivered in large volumes across several days rather than to anchor the national grid on its own. If the 2029 target holds, it would be the first iron-air deployment of this scale seen anywhere in Europe.
Sources
- Battery Technology | Form Energy
- US 100-hour battery startup Form Energy’s first overseas deployment ‘set to fill a critical gap in Ireland’s power system’ – Energy-Storage.News
