Low-carbon lithium extraction makes deep geothermal plants cost-competitive in future energy systems

Lithium is a critical material for the energy transition, but conventional procurement methods have significant environmental impacts. In this study, we utilize regional energy system optimizations to investigate the techno-economic potential of the low-carbon alternative of direct lithium extraction in deep geothermal plants. We show that geothermal plants will become cost-competitive in conjunction with lithium extraction, even under unfavorable conditions and partially displace photovoltaics, wind power, and storage from future renewable energy systems. Our analysis indicates that the deployment of 33 deep geothermal plants in municipalities in the Upper Rhine Graben area in Germany could provide enough lithium to produce about 1.2 million electric vehicle battery packs per year, equivalent to 70% of today`s annual electric vehicle registrations in the European Union. As this number represents only a small fraction of the techno-economic potential in Germany, this lithium extraction process could offer significant environmental benefits. High potential for mass application also exists in other countries, such as the United States, United Kingdom, France, and Italy, highlighting the importance of further research and development of this technology.