Q?ENERGY and Velto Renewables have inaugurated Europe’s largest floating PV plant in the Haute?Marne region of France.

Comprising over 135,000 solar panels mounted on innovative, French?designed floats, the plant spans 127 hectares of former gravel pits owned by Établissements Blandin. With a capacity of 74.3 MWp, it will supply clean energy to 37,000 people annually—covering 65 % of the Saint Dizier, Der et Blaise conurbation. The project is expected to avoid 18,000 tonnes of CO emissions each year.

The inauguration was attended by Marie?Claude Saget Thyes, Mayor of Perthes; Charles de Courson, Member of Parliament for Marne; and Anne Catherine De Tourtier, President of France Renouvelables, along with the project’s consortium teams: Solutions30, Ciel & Terre, Perpetum, and Velto Renewables.

A pioneering developer employs an innovative solution to revitalize anthropogenic land.

Q ENERGY began the “Les Îlots Blandin” project in 2019, aiming to redevelop a former wasteland to support the region’s energy transition and stimulate the local economy. The goal was to reintroduce economic activity into quarry basins flooded after operations ended in 2020.

According to Velto Renewables, this site posed no land?use conflicts due to its nature. After more than five years of development, construction began in September?2023, with commissioning in June?2025.

Corentin SIVY, Development Director of Q ENERGY France, stated that the relationships built “over more than a decade with municipal politicians, public administrations, and the local economic network allow us to develop projects with a detailed understanding of this region’s specific characteristics and challenges. Without these relationships, a project like this would not have been possible.”

Floating solar is a promising technology, especially in northern France, where it can help exploit the country’s solar potential. Beyond the technical feat, ensuring profitability remains one of the main challenges for designing these parks. Most French floating solar projects share this issue, competing in the same CRE tenders as ground?mounted solar—despite higher construction and maintenance costs. Guaranteeing profitability at Îlots Blandin required extensive planning before reaching its current version, which also includes 2 MW of ground?mounted installations to optimize site production.

A project of this scale wouldn’t have been possible without Q?ENERGY forming a group of private partners dedicated to its execution. Ciel & Terre supplied and installed anchors, floats, modules, and inverters; Perpetum handled procurement of inverters and 16 delivery and transformation centers and built the on?land power plant to complement the floating system; and Solutions30, project consortium leader, managed all wiring, connections, and commissioning.

Following Q ENERGY’s financing in September?2024—secured through over €50?million from Crédit Agricole Transitions & Energies and Bpifrance—the first quarter of?2025 saw the acquisition of half the project by Velto Renewables, a Spanish renewable energy company backed by La Caisse, a global investment group.

Lucas de Haro, CEO of Velto Renewables, remarked, “Velto is intensifying its expansion in France with a clear goal: to establish a long term presence in the country over decades. We have come here to stay. We are dedicated to developing, managing, and supporting long?term projects, in harmony with local specificities—and this is one of the reasons we are proud of our partnership with Q ENERGY in France.”