France's largest battery storage plant goes online near Reims
TagEnergy's 240-megawatt facility, built from 140 Tesla Megapacks, fed 70.5 gigawatt-hours back to the grid in its first four months.
TagEnergy has inaugurated a 240-megawatt, 480-megawatt-hour battery storage plant at Cernay-lès-Reims in northeastern France, the country's largest operating battery energy storage project.
The facility, made up of 140 Tesla Megapack battery containers on just over 3 hectares, connects to the high-voltage grid run by transmission operator RTE and provides services that keep the grid's frequency and voltage stable. It was inaugurated Oct. 1 after four months of operation, during which it fed 70.5 gigawatt-hours back into the grid and completed 145 full charge cycles over 125 days.
TagEnergy chief executive Franck Woitiez said the project shows large-scale electricity storage has become an industrial reality in France.
TagEnergy, founded in 2019, owns the plant jointly with Banque des Territoires, the French public investment bank, which bought a 49% stake in 2025. It is the first project under a three-year partnership between the two to finance several large battery plants in France. ABN AMRO, NORD/LB and Caisse d'Épargne CEPAC financed the project.
Banque des Territoires said battery storage is set to play a growing role in France's low-carbon power system but still struggles to win bank financing because its business models are relatively new.
This brief is based on reporting by Gwénaëlle Deboutte, published Oct. 7, 2026, in pv magazine. Read the original: https://www.pv-magazine.com/2026/10/07/frances-largest-battery-goes-online/
This article was produced with the assistance of AI tools and reviewed by an editor before publication.
