The project in Ville-sur-Haine will consist of 53 "Megapack" battery units from Tesla, able to deliver power for 4 hours or 200 megawatt-hours in all.

Such storage projects are expected to become increasingly important in coming years as increasing amounts of electricity is being generated from renewable sources such as solar and wind.

Eneco is controlled by Japan's Mitsubishi Corp.

(Reporting by Toby Sterling; editing by Jason Neely)