Alpiq has acquired the Cheviré operational battery energy storage system (BESS) in western France from Harmony Energy, expanding its push into flexible assets used to balance renewable power and support grid stability. The Swiss energy company said the deal closed on January 21, 2026, and described Cheviré as the largest battery storage facility currently operating in France.
Located in the port of Nantes Saint-Nazaire, the Cheviré site has 100 megawatts (MW) of power capacity and 200 megawatt-hours (MWh) of energy capacity. Commissioned in December 2025, the facility can provide ancillary services to the French electricity grid, including rapid-response support for frequency stability. Alpiq also said the asset could, if required, cover the electricity needs of roughly 170,000 households for two hours—more than the entire city of Nantes.
Alpiq framed the acquisition as a key step in its broader strategy to expand flexible generation and storage, which it says is increasingly necessary as wind and solar output grows and becomes a larger share of national power mixes. Beyond batteries, the company pointed to other flexibility resources such as pumped storage hydropower as critical tools for managing volatility in renewable production and stabilizing grids within fractions of a second.
Cheviré was developed and commissioned by Harmony Energy, a European energy storage developer founded in the United Kingdom in 2010. Harmony launched its French subsidiary in early 2022 to advance battery storage projects in the country. The Cheviré BESS sits on the site of a former fossil-fuel power plant that operated with coal, gas, and oil from 1954 to 1986, positioning the project as a symbolic redevelopment tied to France’s energy transition.
The transaction is Alpiq’s second operating footprint in France. The company said it is also developing another 100 MW battery storage facility in La Corne-en-Vexin that is expected to become operational in 2027. More broadly, Alpiq reported it has secured a battery storage pipeline of more than 750 MW across France, Germany, and the Nordics, with nearly half of that capacity already operational or under construction. Over the next few years, the company expects its storage portfolio to expand to multiple gigawatts as it pursues additional investments in key European markets.
Alpiq also highlighted its existing commercial presence in France, where it has operated since 2002 and has become one of the country’s leading electricity and gas suppliers. In 2025, Alpiq said it supplied more than 25 terawatt-hours (TWh) of energy to French customers and purchased about 5 TWh of electricity, primarily generated from renewable sources. The company also noted it bundles and markets power from decentralized production facilities totaling around 2,000 MW of installed capacity, positioning that activity as part of its role in integrating renewables and providing flexibility solutions. Alpiq added that it recently signed a strategic partnership agreement with Vialis in early December 2025 related to the development of the Lac Blanc / Lac Noir hydropower project in the Vosges.
KEY QUOTE:
“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. 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.”
Amédée Murisier, Head of Business Division Assets and Member of the Alpiq Executive Board
