Europe’s largest floating solar power plant, named Les Ilots Blandin, has been officially inaugurated by Q ENERGY and Velto Renewables in Perthes, Haute-Marne, attended by local officials and representatives from participating companies. The solar park, comprising more than 135,000 panels installed across 127 hectares of former gravel pits owned by Établissements Blandin, has a total installed capacity of 74.3 megawatt-peak (MWp). According to data provided during the event, this infrastructure will annually supply electricity to approximately 37,000 inhabitants, equating to roughly 65% of the population of the Saint-Dizier, Der et Blaise urban community. Project developers estimate an annual reduction in carbon dioxide (CO₂) emissions of 18,000 tonnes thanks to the plant’s operation.
Technical and economic conception of the project
Initiated in 2019 by Q ENERGY, the project required more than five years of development before entering its construction phase in September 2023 and beginning commercial operations in June 2025. The main objective, according to the company, was to enhance a previously artificialized area with no other economic use. To optimize the profitability of the floating solar park, deemed problematic by the operator due to higher costs compared to ground installations, Q ENERGY also included a complementary ground-mounted installation of two megawatts to balance costs and maximize electricity production.
All floats supporting the solar panels were designed and manufactured by the French company Ciel & Terre, which also oversaw the installation of photovoltaic modules and anchoring systems. Additionally, the company Perpetum handled the acquisition of inverters and electrical transformation stations as well as the construction of the complementary ground-based photovoltaic park. Solutions30, appointed by the consortium, undertook essential electrical work including wiring, grid connection, and commissioning.
Funding and project perspectives
Initial funding for the project was arranged in September 2024 by Q ENERGY, raising more than €50mn ($54.47mn) through Crédit Agricole Transitions & Énergies and Bpifrance. In the first quarter of 2025, the Spanish company Velto Renewables, backed by global investment group La Caisse, acquired 50% of the project. During the inauguration, Lucas de Haro, Chief Executive Officer (CEO) of Velto Renewables, highlighted the strategic importance of this partnership in France, affirming that his company intended to sustainably expand within French territory.
Also present at the event, Corentin Sivy, Development Director of Q ENERGY France, recalled that the company has already operated two wind farms in the region since 2010, accumulating a total renewable electricity production capacity of 274 MW in this territory to date. According to his statements, a thorough understanding of local economic and institutional stakeholders was essential to the success of the Les Ilots Blandin project.
