Geothermal energy in France: a snapshot in 2025

As of the end of 2025, geothermal energy in France is strong of 209 000 shallow geothermal systems (< 200 m) and 73 deep systems that produce heat for a total of 7.1 TWh. In addition, France has two systems that produce electricity using EGS technology in Soultz-sous-Forêt in Alsace and Bouillante on the overseas island of Guadeloupe in the East Caribbean. While shallow geothermal systems can be installed broadly in the whole French territory, deep systems require specific conditions that are mostly found in the two main sedimentary basins, the Paris Basin to the north and the Aquitanian Basin to the west. In these two basins, as well as the basins of the ECRIS system, the development is the most dynamic with 19 permits for the development of heat production. The Rhine Graben, that hosts Soultz-sous-Forêt, sees the development of a combined heat and lithium development with 7 ongoing research permits. In addition, strong developments are happening in French overseas volcanic islands, both in the Caribbean (Guadeloupe and Martinique) and in the Indian Ocean (La Réunion and Mayotte), with 8 research permits delivered.For its development, the French government has implemented financial support that covers several aspects from risks at the drilling stage to long-term risks. In 2023, the French government has put forward an action plan to accelerate geothermal development with 27 main actions that aim at increasing in 2028 the produced heat and electricity from geothermal. In the French geothermal energy ecosystem, and to contribute to the national action plan, the BRGM is a major contributor for the geothermal energy resources assessment. For deep geothermal, the BRGM is investigating the resources both through existing data at regional scale (GeoScan Hexagone with first application in Paris Basin) and in dedicated geothermal areas with new acquisitions (GeoScan Arc and GeoScan IdF). In addition, favourability maps have been or are being finalised for open and closed loop shallow geothermal systems. Overall, France is a dynamic territory for a diverse range of geothermal energy, from shallow to deep and high enthalpy systems with a strong aim to develop further in the near future.