• Neoen announces the launch of the largest battery in France, with a capacity of 496 MWh
• Located in Vernou-la-Celle-sur-Seine, 90km km southeast of Paris, this battery will support the Île-de-France area of the electricity network
• Nidec ASI will supply the battery modules, which will be assembled in France, near Saint-Étienne
• Construction is scheduled to begin in the summer of 2026, with the asset expected to start operating in 2028

Neoen, one of the world’s leading renewable energy companies, has signed a contract with the Japanese group Nidec ASI for the construction of its Vernou-la-Celle-sur-Seine battery. With an installed capacity of 248 MW / 496 MWh, it will be the largest battery in France and the first to be connected to RTE’s 400 kV high voltage transmission network. Construction is scheduled to begin in the summer of 2026, with the asset expected to start operating in 2028.

The battery packs will be assembled in France by Nidec at its new production facility in La Fouillouse, near Saint-Étienne. This order from Neoen supports the growth of Nidec’s business in France, which recently announced plans to double the production capacity of this facility. Nidec will also be responsible for the maintenance of the storage system for the next 20 years.

Located close to the Chesnoy substation which supports the Paris metropolitan area, this battery, with a capacity of 200 MW at the point of connection, will provide frequency and voltage regulation services to the French electricity grid. It will help to relieve congestion in the Île-de-France area of the electricity network as well as enable a higher penetration of renewable energy.

As part of ongoing community engagement, a committee consisting of members of the local council of Vernou-la-Celle-sur-Seine, a local association, public authorities, and the sub-prefecture of Fontainebleau, has been set up. Additional studies will be completed prior to the start of construction to ensure the project is fully integrated into its environment. In addition, Neoen will fund local projects related to sustainable development, such as energy-efficiency upgrades for public buildings. Local residents will also receive direct economic benefits through vouchers that will help them to reduce their energy bills.

With the announcement of this new battery, Neoen cements its position as France’s leading independent renewable energy company. This is its second large-scale storage project after Breizh Big Battery (92 MW / 183 MWh) in Pleyber-Christ, Brittany, which is currently nearing completion. In France, Neoen has a portfolio of 2.2 GW under construction, in operation, or under management, spread across its three technologies: solar, onshore wind, and battery storage.

Guillaume Decaen, CEO of Neoen France, said: “After several years of development and engagement with residents and local organisations, we are proud to see this exceptional project come to life. This battery will contribute significantly to the protection and stability of the Île-de-France network and will enable Neoen to offer innovative solutions to its customers. Ten years after delivering France’s largest solar farm at Cestas, Neoen is demonstrating that renewable energy generation and large-scale storage are taking their place in the energy mix of our country.”

Xavier Barbaro, Group CEO of Neoen, said: “Neoen has developed a unique know-how in energy storage around the world, and is now contributing this expertise to France. This major project is also a testimony to the strong relationship we have with our partner Nidec: it will be our twelfth battery together, totaling over 1 GWh of cumulative capacity. We are delighted to be able to make this announcement during President Macron’s visit to Japan, illustrating the ability of our two countries to cooperate and work together on the energy transition.”