Ore Energy Signs Europe's Largest Iron-Air Battery Deal, Committing 1 GWh of Multi-Day Storage to Dutch Supplier Budget Thuis

Overview

Amsterdam-based startup Ore Energy has signed an agreement to deploy up to 1 gigawatt-hour of iron-air long-duration energy storage for Dutch energy supplier Budget Thuis, with a committed first phase of 400 megawatt-hours scheduled for delivery in 2028, according to Energy-Storage.News. POWER Magazine described the agreement as the largest iron-air energy storage offtake in continental Europe to date, and the first with a European energy supplier.

What We Know

The deal pairs a multi-day storage technology with a mass-market retailer. Budget Thuis is one of the largest energy suppliers in the Netherlands, serving more than 1 million customers, and is part of Nuts Groep, as reported by ESS News.

Ore Energy’s batteries can store electricity for up to 100 hours, in contrast to lithium-ion systems that are typically designed to deliver energy over a few hours, according to Electrek. The same outlet notes that the technology uses iron, water, and air and is designed to help fill multi-day gaps in renewable energy generation. The cells can be configured for discharge durations ranging from 24 to 100 hours, Electrek reported, and Ore Energy packages each system as a megawatt-hour-scale unit inside a 40-foot enclosure, per Energy-Storage.News.

The chemistry relies on reversible rusting. During discharge, metallic iron oxidizes — rusts — releasing electrons and generating current, and during charging an electrical current reverses the rust back into metallic iron, according to Silicon Canals. Because the system uses only iron, water, and air, Ore Energy says it can rely on a European supply chain and avoid many of the critical minerals used in conventional batteries, Electrek reported.

The agreement follows a pilot with French utility EDF. In February, Ore Energy announced the completion of a project it described as Europe’s first grid-connected iron-air long-duration storage pilot; conducted between August and November 2025, it demonstrated up to four days of energy storage under real-world utility conditions, according to Electrek.

Aytaç Yilmaz, cofounder and CEO of Ore Energy, framed the deal around grid curtailment. “European grids are already curtailing clean power at scale, wasting electricity that costs billions to generate, while we stay dependent on fossil fuels to cover the gaps,” he said, according to Electrek. Yilmaz added: “We believe iron-air will become as important for wind as lithium-ion has been for solar,” as reported by ESS News.

For the buyer, the rationale is price stability. Annemarie Buitelaar, CEO of Budget Thuis, said the deployment is “about reducing exposure to volatile fossil fuel prices while giving customers access to cleaner and more predictable electricity over time,” according to Electrek.

Ore Energy is a science startup spun out of TU Delft and was founded in 2022, according to Energy-Storage.News. The company emerged from stealth with €10 million in funding from Positron Ventures and SPRIND, Silicon Canals reported.

What We Don’t Know

The published reporting does not disclose the financial value of the Budget Thuis offtake or the timeline for phases beyond the initial 400 megawatt-hours. It also does not specify where in the Netherlands the systems will be sited or the expected round-trip efficiency of the deployed units.