Ore Energy Pilots 100-Hour Iron-Air BESS at EDF Lab in France

Why It Matters

The pilot provides the first real‑world evidence that iron‑air batteries can reliably balance renewable generation over days, a critical gap for European grids seeking cost‑effective decarbonisation.

Key Takeaways

• First European 100‑hour iron‑air pilot completed
• Demonstrated multi‑day storage under real utility conditions
• Uses abundant iron, water, air; no rare‑earths
• Targets long‑duration storage, cheaper than lithium‑ion beyond 12 h
• Ore plans European manufacturing facility by 2027

Pulse Analysis

The 100‑hour iron‑air battery pilot completed by Ore Energy at EDF’s Lab les Renardières marks the first multi‑day long‑duration energy storage (LDES) demonstration in Europe. Over several months the modular container system was grid‑connected, cycled through varied load profiles and seasonal conditions, and proved operable in a live utility environment. The test moves beyond the earlier Dutch installation, shifting focus from basic grid‑connection to real‑world behavior, control strategies, and integration with standard grid‑management tools. Data gathered will feed the EU’s StoRIES program, which seeks scalable solutions for balancing wind and solar output over days rather than hours.

Iron‑air technology stores energy by reducing iron oxide to metallic iron during charging and re‑oxidising it on discharge, using only iron, water and air. This chemistry eliminates rare‑earths and critical minerals, enabling a fully European supply chain from production to end‑of‑life. While round‑trip efficiency figures remain undisclosed, the chemistry is inherently low‑cost for durations beyond 12 hours, where lithium‑ion costs rise linearly with storage time. Analysts expect the levelized cost of storage (LCOS) to undercut lithium‑ion in the multi‑day segment, making iron‑air an attractive option for utilities facing prolonged renewable lulls.

The pilot arrives as Europe accelerates its renewable‑energy targets and seeks to close the multi‑day storage gap. Competitors such as Form Energy in the United States and Ireland’s FuturEnergy are also pursuing iron‑air projects, but Ore Energy is currently the sole European operator with in‑house manufacturing in Amsterdam and plans for a dedicated plant by 2027. Policy frameworks like the EU’s Storage Research Infrastructure and growing utility interest suggest a fertile market for LDES. If the forthcoming performance data confirm reliability and cost advantages, iron‑air could become a cornerstone of Europe’s decarbonisation strategy, complementing short‑duration batteries and emerging hydrogen solutions.

Ore Energy pilots 100-hour iron-air BESS at EDF lab in France

Ore Energy pilots 100-hour iron‑air BESS at EDF lab in France · By April Bonner · February 11, 2026

Netherlands‑based iron‑air long‑duration energy storage (LDES) startup Ore Energy has completed a grid‑connected pilot of its 100‑hour iron‑air LDES system at EDF Lab les Renardières in France.

The pilot builds on Ore Energy’s recent grid‑connected installation in Delft, the Netherlands, which the company says showcases the potential for integrating iron‑air systems into existing European distribution networks.

Responding to Energy‑Storage.news’ request for comment, a spokesperson for Ore stated of the project:

“The EDF pilot was structured as a feasibility and operability evaluation, focused on how a multi‑day iron‑air system behaves in a live utility environment over extended discharge periods. The emphasis was on system behaviour, control, and integration.”

They continued, “By contrast, the earlier Netherlands project focused more narrowly on proving that an iron‑air system could be safely and reliably connected to the grid and operated as intended. The key difference is the move from ‘can this connect and run?’ to ‘how does this behave over multi‑day timescales under real‑world utility conditions?’ This also meant a larger overall system configuration and more cycles with varied charge/discharge characteristics.”

Ore stated that the pilot was the first of its kind in Europe, and demonstrated the company’s iron‑air LDES technology’s ability to deliver multi‑day energy storage.

As part of the EU’s Storage Research Infrastructure Eco‑System (StoRIES)‑supported pilot, Ore Energy installed its modular iron‑air battery system to gather real‑world operational data under grid conditions. It demonstrated the ability to store and discharge energy for about four days (100 hours). Over several months, the system was tested with different load profiles and seasonal changes to evaluate charge/discharge cycles, responsiveness, and compatibility with standard grid management methods. The data collected supports the StoRIES initiative’s goal of exploring LDES solutions for multi‑day renewable energy balancing.

Ore Energy claims its systems are designed to maximise renewable energy storage and distribution for reliable grid power during windless, sunless periods. Its iron‑air system uses iron, water, and air to drive a reversible oxidation process.

During charging, excess renewable electricity converts iron oxide into metallic iron, storing energy for up to four days. When discharged, iron is re‑oxidised by oxygen and water, releasing electricity as it rusts again.

These systems rely on abundant resources, with no rare earths or critical minerals, “enabling a 100 % European supply chain from manufacturing to end‑of‑life.” Full‑scale systems use modular 40‑foot containers that deliver multiple MWh of multi‑day storage.

Ore’s spokesperson noted, “The French project was not designed as a performance optimisation or benchmarking exercise, and EDF is not publishing detailed performance metrics such as round‑trip efficiency (RTE), degradation rates, or dispatch profiles from the pilot. What can be said is that the system operated as intended over the assessment period, providing EDF with the data needed to evaluate technical feasibility and operational characteristics of iron‑air storage in a real utility setting.”

Regarding cost comparisons with lithium‑ion, they said:

“Ore Energy is not publishing project‑specific cost or LCOS figures at this stage. That’s in part because it varies greatly depending on the context, use case, and geography. That said, Ore will be able to achieve an LCOS significantly lower than lithium‑ion storage systems at long‑duration.”

They added, “At a directional level, iron‑air systems are not designed to compete with lithium‑ion on short‑duration applications (< 12 hours). Their value proposition is in longer‑duration storage, where lithium‑ion costs scale linearly with duration and become less economical. Because iron and air are abundant, low‑cost materials, iron‑air systems are widely modelled as having lower marginal cost per additional hour of storage beyond the 8–12 hour range. That’s the segment this technology is designed to address.”

Ore Energy is not the first or only company to utilise iron‑air technology. US startup Form Energy is also developing a proprietary iron‑air battery technology that operates through the reversible oxidation (rusting) of iron during discharge. Form Energy, established from MIT labs and led by ex‑Tesla Energy executive Mateo Jaramillo, asserts that its battery can be produced inexpensively with abundant materials, providing a practical ‘multi‑day’ energy storage solution for the grid. The company broke ground on its first project in Cambridge, Minnesota, US, in 2024 and opened a factory in West Virginia the following year.

In the same year, developer FuturEnergy Ireland announced its intentions to build Europe’s first iron‑air BESS. The joint‑venture between state‑owned forestry business Coillte and electricity generation, transmission, and distribution company ESB filed a planning application for the Ballynahone Energy Storage project with Donegal County Council, which granted permission for the project next to Trillick Substation, near Buncrana in County Donegal.

US startup Noon Energy recently launched a 100‑hour+ demonstration project after emerging from stealth mode, using a reversible solid‑oxide fuel‑cell battery.

Ore’s spokesperson highlighted the difference of the company’s technology:

“Ore Energy’s approach to system architecture and modularity (including how iron‑air cells are packaged, daisy‑chained, and controlled within a containerised system to achieve higher MWh capacity) is unique, complemented by a portfolio of granted and pending patents covering aspects of chemistry, mechanical design and electronics. Ore is also the only iron‑air LDES company operating in Europe.”

Additionally, they pointed out that Ore Energy’s systems are manufactured in‑house at the company’s headquarters in Amsterdam. Ore is exploring options in Germany and the Netherlands for its “first‑of‑a‑kind” manufacturing facility, planned to start operations in 2027.