The City of Versailles in the Yvelines Department in France has signed a contract with Engie for a 32-year concession that seeks to transform and modernize the local district heating network. The project will involve the drilling of a geothermal doublet which will supply 69% of the network’s heating requirements by 203o.
The contract between the two parties was signed by Versailles Mayor François de Mazières and Engie Managing Director Franck Lacroix. The project will be managed and operated by Engie through local subsidiary Verseo Geo.
“This is a strategic project for our city. It will be one of the major issues in the coming years, with large-scale construction projects, the development of the network in the city center, its extension onto the Satory plateau, as well as a complete modernization of existing facilities. This reinforces our sustainable city policy, which has been in place for many years in a historic city with a remarkable heritage. Geothermal energy is the discreet and permanent energy source that needed to be developed ,” said Mazières.
Two geothermal boreholes will be drilled to depths of around 1500 meters at the site of the current boiler room on Avenue du Maréchal-Juin. Thermal waters reaching temperatures of 60 °C are expected to be extracted from these boreholes. According to the project partners, the transition to geothermal will reduce CO2 emissions by 900,000 tonnes, or about 70% of the current amount. About 69% of the heating requirements will be supplied by geothermal, with the rest to be supplied by three existing gas boilers.
Engie will be investing EUR 110 million towards the project. The complete project is expected to take around 10 years. An initial phase from July 2026 to October 2031 will focus on the city center of Versailles, while a follow-up expansion from April 2027 to June 2035 will progress towards the Satory district. In total, the geothermal network will be extended to 35 kilometers from the current 18 kilometers.
Activity on geothermal heating projects in the Île-de-France region remains high, further expanding on decades of history and experience. Before the end of 2025, a new geothermal heating plant was inaugurated in the commune of Saint-Denis, operated as well by an Engie subsidiary. France had previously published a geothermal action plan and a set of concrete measures establishing a roadmap to quadruple the deployment of deep geothermal projects by 2035.
Source: MesInfos and Ville de Versailles via Facebook
