Neoen Partners with Nidec to Deliver France’s Grid-Scale Battery Energy Storage System

Neoen has signed a contract with Nidec ASI to build France’s largest 248 MW / 496 MWh battery energy storage system in Vernou-la-Celle-sur-Seine, near Paris, France. 

The battery units will be manufactured and assembled in France by Nidec ASI at its newly established facility in La Fouillouse, near Saint-Étienne, and the company will also handle maintenance of the system over 20 years. Situated near the Chesnoy substation, which serves the Paris metropolitan region, the 200 MW battery will deliver frequency and voltage regulation services to the French power grid. It is expected to ease network congestion in the Île-de-France region while supporting greater integration of renewable energy sources. 

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. 

With this new battery announcement, Neoen reinforces its position as France’s leading independent renewable energy producer. The project marks its second major storage initiative, following the Breizh Big Battery (92 MW / 183 MWh) in Pleyber-Christ, Brittany, which is close to completion. In France, the company currently holds a portfolio of 2.2 GW across operational projects, under construction, or being managed, spanning solar, onshore wind, and battery storage technologies.