TL;DR
Neoen is launching France’s largest battery project in Vernou-la-Celle-sur-Seine with a 248 MW / 496 MWh capacity. Connected to the 400 kV grid, it will stabilize energy flow and integrate renewables. Partnering with Nidec, the batteries will be assembled locally in France. Construction starts in 2026, targeting operations by 2028 to bolster national grid reliability.
PROJECT SNAPSHOT
Company: Neoen
France Project Capacity: 248 MW / 496 MWh
Japan Project Capacity: 100 MW / 400 MWh
Location (France): Vernou-la-Celle-sur-Seine
Location (Japan): Hyogo Prefecture
Technology: Battery Energy Storage System (BESS)
Construction Start: 2026
Commissioning: 2028
Partners: Nidec ASI (France), Equans & Toho (Japan)
Grid Connection: 400 kV transmission network (France)
Neoen, one of the world’s leading renewable energy companies based in France, announced new developments in its native market. It signed a contract with Japan-based Nidec ASI for the construction of its battery project at Vernou-la-Celle-sur-Seine, some 90 kilometers southeast of Paris. It marked an entry into the Japanese energy storage market as a first project in the country.
Neoen plans to build France’s largest battery, a 248 MW / 496 MWh BESS will support the Île-de-France electricity network, with construction starting in summer 2026 and operations expected in 2028. This project will be the first to be connected to RTE’s 400 kV high voltage transmission network.
Nidec will assemble the battery packs at its newly expanded facility in La Fouillouse, near Saint-Étienne. It will strengthen Neoen’s longstanding collaboration with Japan’s Nidec business in France, it is planning to double the production capacity for this facility. For the next two decades, Nidec is responsible for the maintenance of the storage system.
Located near Chesnoy substation and supporting the Paris metropolitan area, this 200 MW battery system will provide frequency and voltage regulation services to the French electricity grid. It helps to reduce pressure in Île-de-France and make it easier to bring more penetration of renewable energy.
A committee was overseeing as part of ongoing community engagement, having members of the local council of Vernou-la-Celle-sur-Seine, a local association, public authorities, and the sub-prefecture of Fontainebleau. Extra studies are being conducted before construction to ensure the project is fully integrated into its environment. Neoen is financing sustainable development projects, such as upgrading the energy efficiency of public buildings. Residents will benefit economically with this project through vouchers in the form of lowering the energy bills.
Neoen is positioning as France’s leading independent renewable energy company with this announcement. After the current project, Breizh Big Battery (92 MW / 183 MWh) in Pleyber-Christ, Brittany, which is nearing the completion, this is Neoen’s second large-scale storage project. Across its three technologies in France: solar, onshore wind, and battery storage, Neoen has a portfolio of 2.2 GW under construction, in operation, or under management.
Guillaume Decaen, CEO of Neoen France, stated that after years of project development and coordination with local residents and organisations, the project has reached the implementation stage. Protection and stability of the Île-de-France network is supported by this battery and also it helps Neoen to offer innovative solutions to its customers. A decade after opening France’s largest solar farm in Cestas, in France, Neoen is exhibiting that renewable energy generation and large-scale storage are taking their place in the energy mix.
Xavier Barbaro, Group CEO of Neoen, stated about the company’s global expertise in energy storage as they launch a unique new project in France. He also stated that this major project marks their twelfth collaboration with Nidec, bringing their combined capacity to over 1 GWh. He also announced this partnership during President Macron’s visit to Japan, calling it a perfect example of French-Japanese cooperation and working together in this energy transition.