France Opens Europe’s Largest Floating Solar Farm on Former Gravel Pits

France has transformed a former gravel quarry in Haute-Marne into Europe’s largest floating solar farm, with more than 135,000 solar panels spread across 127 hectares. The Les Îlots Blandin project, located near Perthes, has an installed capacity of 74.3 megawatts-peak (MWp) and is expected to generate enough renewable electricity to meet the annual needs of around 37,000 people.

Developed by Q ENERGY and now wholly owned by Velto Renewables, the facility was officially inaugurated on June 20, 2025. It is also expected to prevent approximately 18,000 tonnes of carbon dioxide emissions each year.

The project uses six water-filled basins left behind by gravel extraction at the Blandin site. Quarry operations ended in 2020, leaving an area that could be repurposed for renewable energy generation rather than requiring an entirely new site.

The project has a total installed capacity of 74.3 MWp. Approximately 72.3 MW comes from the floating installation, while a 2 MW ground-mounted section supplements its output.

Construction began in September 2023 and took around 15 months, according to project information published by Q ENERGY and Grand Est Development International.

The facility is designed to produce enough renewable electricity each year to meet the equivalent of the annual consumption of approximately 37,000 people. It is also expected to avoid around 18,000 tonnes of CO₂ emissions annually.

Q ENERGY initiated the project and worked with several specialist companies. Ciel & Terre supplied the floating solar structures.

while PerPetum handled electrical infrastructure and the ground-mounted installation. Solutions30 was responsible for cabling, grid connection and commissioning.

In September 2024, Q ENERGY announced that the project had secured €50.4 million in financing arranged by Crédit Agricole Transitions & Énergies and Bpifrance.

Velto Renewables, which previously held a 50% stake, completed its acquisition of the remaining interest in November 2025, becoming the facility’s sole owner.