Alpiq is consistently pursuing its growth strategy in the area of flexible assets: the Swiss energy company has acquired the Cheviré operational battery storage facility in the port of Nantes Saint-Nazaire (France) from Harmony Energy, a leading European developer of battery energy storage systems (BESS). With an output of 100 megawatts (MW) and a capacity of 200 megawatt hours (MWh), it is currently the largest battery storage facility in the country. The facility in western France was inaugurated in December 2025 and can provide ancillary services for the national electricity grid or cover the electricity needs of 170,000 households for two hours.
With the acquisition of the Cheviré operational battery storage facility in the port of Nantes Saint-Nazaire in France on 21.01.2026, Alpiq is once again underlining its commitment to better integrating the rapidly growing production of electricity from renewable energy sources into the energy system, thereby contributing to a sustainable energy future. Battery storage facilities and other flexible assets, such as pumped storage hydropower plants, are indispensable for balancing the volatility of electricity production from wind and solar energy and stabilising grid frequency within a fraction of a second.
“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,” says Amédée Murisier, Head of Business Division Assets and member of the Alpiq Executive Board. “Flexibility is key to integrating renewable energy and ensuring the stability of electricity grids. We are investing specifically in flexible power plants and storage facilities that help strengthen security of supply and deliver sustainable solutions for our customers. France is a strategic market in this regard, and Cheviré represents a milestone on our path to strengthening and further expanding our position as a provider of flexibility solutions in Europe.”
In terms of installed capacity (100 MW) and storage capacity (200 MWh), the Cheviré BESS is currently the largest battery storage facility in operation in France and in Alpiq’s portfolio of operating BESS assets. It is an important element in the country’s security of electricity supply and a powerful symbol of the energy transition. The battery storage facility is located on the site of the former Cheviré fossil-fuel power plant, which was operated using coal, gas and oil from 1954 to 1986. The BESS can use stored electricity, mainly from climate-friendly production, to provide important ancillary services for the national electricity grid. If required, it can also supply 170,000 households – more than the entire city of Nantes – with electricity for two hours.
The Cheviré BESS was developed and commissioned by Harmony Energy, a leading European developer of energy storage projects. Harmony Energy was founded in the United Kingdom in 2010, followed by the establishment of its subsidiary, Harmony Energy France, in early 2022 to implement storage projects in France.
