Harmony Energy has energised the Cheviré battery project, now the largest BESS in France.
The 100MW / 200MWh facility, located in the port of Nantes Saint-Nazaire Harbour, is the country’s first large-scale, two-hour duration storage project.
Built on the site of the former Cheviré fossil fuel power plant, which operated between 1954 and 1986, the system is positioned next to the grid operator’s substation.
Equipped with Tesla’s Megapack and Autobidder technologies, the project will provide balancing services to the national grid.
With the capacity to power about 170,000 homes for two hours, Harmony Energy said the facility will support grid resilience, reduce carbon emissions, and help cut energy costs and volatility.
Andy Symonds, CEO of Harmony Energy France, said: “The Cheviré battery project is a landmark achievement for the wider energy transition in France.
It shows how disused industrial sites can be repurposed to enable a more sustainable electrification of our power systems.
This project strengthens energy security, supports affordability, and helps pave the way for a cleaner energy system which is less reliant on burning fossil fuels.
“We began construction on site in summer 2024 and have just achieved energisation, one year later, showcasing how expertise, skill and productive collaboration between teams working on a shared goal can accelerate the transition to net zero.”
Harmony Energy added that the project includes biodiversity initiatives and a community benefit fund, alongside commitments to social and environmental causes.
[Image caption: Harmony Energy Parc de Chevire Andy Symonds Clement Girard. Image credit: Harmony Energy]
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