The Soultz-sous-Forêt geothermal power station is the only pilot project of its kind today in France today that is carrying out deep geothermal power generation. Scientific results achieved by the project so far and still to come will be of great significance in the development of the fault basin geothermal energy sector. The project involves developing the use of a geothermal water resource that circulates by convection in the naturally fractured granite bedrock. This technology, known as EGS (Enhanced Geothermal System) is, at the present time, unique in France in terms of its advanced scientific and industrial stage of development.

The outcomes of the Soultz-sous-Forêt plot project are already effective in terms of industrial development. The ES Group and its subsidiary ESG have used the results of this research to assist them in developing the ecoGI project, the first industrial project in France to recover heat obtained by extracting geothermal water, and use it to supply a factory for 8,000 hours per year. A system of heat exchangers extracts calories from this water, which is at 165°, and immediately re-injects it into its natural environment.

Thanks to the Soultz-sous-Forêts site, ÉS Géothermie, a subsidiary of the ES Group, has been able to take advantage of a unique set of skills which have enabled it to check the potential of geothermal energy, respond to the scientific challenges involved, perfect the techniques for using the energy and use them for new projects currently being explored in the Alsace area, and indeed in other European countries.

1997 / First geothermal circuit in the world put into operation – four 3,500 metre deep bore holes– production of electricity providing installed electrical power of 1.5 megawatts – Commissioned in 2008.

Main stakeholder


26 Boulevard du président Wilson

Players involved and their roles