| Abstract |
Due to its large diversity of geothermal resources, France has set up ambitious objectives for the development of each type of geothermal energy. The use of geothermal heat is expected to be multiplied by 6 between 2006 and 2020, thanks to the use of ground-source heat pumps as well as geothermal district heating. This development, supported for long by efficient risk mitigation schemes, has been boosted by the implementation of a renewable heat fund. Geothermal power capacity must increase from 17 MW to 80 MW during the same period, in order to replace the use of fossil fuels for power production in overseas departments and to improve the French know-how in EGS. In this context, industry formed a dedicated professional association (AFPG) in 2010 and ADEME produced a strategic geothermal roadmap in closed link with industry and experts. Several years after the definition of these objectives, the situation for ground-source heat pumps remains unsatisfactory: the market is very hard for individual housing, with a significant decrease these last five years. The situation is better in office buildings where the possibility to have a single system for heating and cooling is appreciated. Some work is being done in terms of standards, certification and environmental regulation. The French thermal regulation for buildings, focusing only on primary energy, does not help geothermal energy. France has a remarkable experience in geothermal district heating: 37 doublets or triplets are operating in the Dogger aquifer of the Paris basin, which is a unique concentration in the world in terms of low enthalpy. There have been many new doublets and rehabilitations of existing doublets since 2007, and many others are still expected in the next years. A specific management of the Dogger aquifer has been put in place to prevent use conflicts. In addition, some operations are also carried out in the intermediate aquifers of the Paris basin (at a 600-1000m depth), as the Albian and the Neocomian aquifers. Two different contexts should be distinguished for power production: in overseas department, geothermal energy must be developed to enhance the energy independence of these territories. The single existing power plant, located in Bouillante in Guadeloupe, encountered technical and social issues from 2009 to 2012 but is now running again properly. A partial reinjection has been put in place and the first power unit has been rebuilt. Surface exploration has been carried out in Martinique Island. In Dominica, the geothermal potential has been estimated through exploration drillings paid by the French Agency for Development and an interconnection with Guadeloupe and/or Martinique is envisaged. In the mainland, the Soultz EGS pilot plant, which is a worldwide reference, has been connected to the grid. It also inspired Ecogi project, which aims at producing industrial vapor: the first well has been realized and the second one will be drilled in 2014. Thanks to the new feed-in tariff put in place in 2010, many CHP projects are emerging and will allow France to develop its expertise in EGS: 8 permits have been delivered and 10 other are under examination. To boost innovation, the French government has put in place the “Investment for the Future” programme that funds several RD&D actions: we can mention notably two demonstration projects in high enthalpy, Fongeosec in the south-west of France and Geotref in the French West Indies, a laboratory of excellence “G-Eau-Thermie Profonde” located in Strasbourg and a project of Institute of Excellence, Geodenergies, which aims at developing underground technologies for decarbonated energies. In addition, the government launched in 2013 a huge debate on energy transition to update the environmental policy that was determined in 2007 through the “Grenelle Environnement” process. |