Jan 8, 2026
Versailles, France, is set to implement a geothermal transition for its heating network.
The City of Versailles, located in the Yvelines Department of France, has entered into a 32-year agreement with Engie aimed at transforming and upgrading the local district heating system. This initiative will include drilling a geothermal doublet to meet 69% of the network's heating needs by 2030.
The contract was finalized by Versailles Mayor François de Mazières and Engie Managing Director Franck Lacroix. Engie will manage and operate the project through its local subsidiary Verseo Geo.
Mayor Mazières stated, “This is a crucial project for our city. It will address significant issues in the coming years, involving extensive construction, network development in the city center, an extension to the Satory plateau, and a thorough modernization of existing infrastructure. This supports our long-standing sustainable city policy in a historic area with a rich heritage. Geothermal energy is the subtle and consistent energy source that we need to further develop.”
To implement the project, two geothermal wells will be drilled to about 1500 meters at the current boiler room site on Avenue du Maréchal-Juin. Thermal waters with temperatures of 60 °C are anticipated to be extracted from these wells. The project partners estimate that transitioning to geothermal energy will cut CO2 emissions by 900,000 tonnes, roughly 70% of the current total. Geothermal sources will supply 69% of heating needs, while the remaining will come from three existing gas boilers.
Engie plans to invest EUR 110 million in this project, which is expected to span approximately 10 years. The initial phase will run from July 2026 to October 2031, focusing on Versailles's city center, followed by an expansion from April 2027 to June 2035 towards the Satory district. Overall, the geothermal network will expand from 18 kilometers to 35 kilometers.
Geothermal heating initiatives in the Île-de-France region are actively progressing, building on several decades of experience. A new geothermal heating plant operated by an Engie subsidiary is set to open in the commune of Saint-Denis before the end of 2025. France has also released a geothermal action plan with specific measures to increase the deployment of deep geothermal projects fourfold by 2035.
The contract was finalized by Versailles Mayor François de Mazières and Engie Managing Director Franck Lacroix. Engie will manage and operate the project through its local subsidiary Verseo Geo.
Mayor Mazières stated, “This is a crucial project for our city. It will address significant issues in the coming years, involving extensive construction, network development in the city center, an extension to the Satory plateau, and a thorough modernization of existing infrastructure. This supports our long-standing sustainable city policy in a historic area with a rich heritage. Geothermal energy is the subtle and consistent energy source that we need to further develop.”
To implement the project, two geothermal wells will be drilled to about 1500 meters at the current boiler room site on Avenue du Maréchal-Juin. Thermal waters with temperatures of 60 °C are anticipated to be extracted from these wells. The project partners estimate that transitioning to geothermal energy will cut CO2 emissions by 900,000 tonnes, roughly 70% of the current total. Geothermal sources will supply 69% of heating needs, while the remaining will come from three existing gas boilers.
Engie plans to invest EUR 110 million in this project, which is expected to span approximately 10 years. The initial phase will run from July 2026 to October 2031, focusing on Versailles's city center, followed by an expansion from April 2027 to June 2035 towards the Satory district. Overall, the geothermal network will expand from 18 kilometers to 35 kilometers.
Geothermal heating initiatives in the Île-de-France region are actively progressing, building on several decades of experience. A new geothermal heating plant operated by an Engie subsidiary is set to open in the commune of Saint-Denis before the end of 2025. France has also released a geothermal action plan with specific measures to increase the deployment of deep geothermal projects fourfold by 2035.