ABSTRACT
Enhanced geothermal systems (EGS) appear as a tangible solution for developing decarbonized electricity production and/or renewable heat at high temperatures for industry in Europe. Based on operational geothermal plants (Soultz-sous-Forêts, Rittershoffen) located in the Upper Rhine Graben (URG), it turns out that thermo-hydro or chemical stimulation techniques could be applied to naturally fractured reservoirs to enhance the hydraulic performance of the geothermal wells. However, the main challenge for EGS is the potential occurrence of induced seismicity related to post-drilling hydraulic stimulation or done during sustainable geothermal exploitation, which could generate severe societal concerns. Moreover, after several years of geothermal exploitation in the URG, there is a very low environmental impact characterized by negligible carbon dioxide emissions. As the exploited geothermal resource trapped in the fractured crystalline reservoirs is a Li-rich brine, it is likely in the near future that geothermal lithium for batteries could be produced with a neutral carbon footprint.
