Researchers at Germany’s Fraunhofer Research Institution for Energy Infrastructures and Geotechnologies have begun developing a mobile lithium extraction plant designed to recover the metal from deep geothermal brines beneath the North German Basin — a geological formation estimated to hold one of Europe’s largest lithium resources.
The work is being carried out under the RoLiXX project, a $3.2 million initiative supported by the German Federal Ministry of Research, Technology and Space, involving Fraunhofer IEG and several academic and industry partners. The target is the Rotliegend — a 300-million-year-old layer of sandstone and volcanic rock several miles below the surface — whose geothermal waters are considered highly promising for lithium extraction. Estimates suggest the basin’s underground reserves could contain up to 1.27 trillion tonnes of lithium equivalent.
The project aims to create a dual-use model in which geothermal heat production and lithium recovery happen simultaneously, allowing operators of existing geothermal facilities to extract lithium without disrupting power generation. The pilot system has been deliberately designed for mobility: it weighs approximately 250 kilograms, occupies roughly two cubic metres and can be transported by van or forklift directly to geothermal sites.
A central engineering challenge is preventing corrosion and mineral buildup inside the extraction system, which the team is addressing through an adaptive plant capable of adjusting process parameters and chemical additives based on the local thermal water composition. The system also employs a solid-free extraction process to avoid mineral residues that could interfere with geothermal infrastructure.
Fraunhofer IEG project manager Tilman Cremer said the initiative demonstrated that critical raw materials could be sourced locally. “Europe needs its own sources of strategic raw materials. By developing lithium resources in the North German Basin, Germany could in the future play a central role in covering both German and European demand,” he said. The team plans to analyse samples and drilling data spanning from the Dutch border to Poland to better understand how lithium accumulates and how it can be safely recovered.
