Swiss utility Alpiq has acquired the 100MW/200MWh Cheviré battery energy storage system (BESS) located in the port of Nantes Saint-Nazaire from developer Harmony Energy, marking a further expansion of its European flexibility portfolio.
The Cheviré facility, inaugurated in December 2025, is currently the largest operational battery storage project in France. Alpiq said the asset can supply electricity equivalent to the needs of around 170,000 households for two hours and provides ancillary services to support stability on the French power grid.
The battery is located on the former site of a fossil-fuel power plant, underlining the shift from conventional generation to flexible, low-carbon infrastructure, the company added.
“The acquisition of the Cheviré battery storage facility marks a milestone in the implementation of our growth strategy in the area of flexible plants and for ensuring a sustainable, secure energy supply,” said Amédée Murisier, head of the assets business division at Alpiq. “Flexibility is key to integrating renewable energy and ensuring the stability of electricity grids.”
Alpiq said the transaction supports its broader strategy to integrate rising volumes of renewable generation into the energy system through storage and other flexible assets.
Cheviré becomes Alpiq’s second asset in France. The company is also developing a 100MW battery storage project at La Corne-en-Vexin, which is scheduled to come online in 2027.
With the acquisition, Alpiq’s secured battery storage portfolio now exceeds 750MW across France, Germany and the Nordic countries, with further investments planned in the coming years, the company said.
