The energy and digital transitions require a large amount of mineral raw materials, some of which are considered ‘critical’ by the European Union. These Critical Raw Materials (CRM) are predominantly imported from non-European countries, subject to high geopolitical risks. However, the EU has largely untapped resources at its disposal in geothermal fluids, some of which contain significant amounts of CRMs. The project CRM-geothermal therefore proposes to combine the extraction of mineral raw materials and geothermal heat, a renewable energy resource from the ground that is available 24 hours per day.
Preliminary calculations show that extraction of CRM from geothermal fluids has the potential to produce significant amounts of the EU needs. Combined extraction of heat and minerals maximises returns on investment, minimises environmental impact, requires no additional land-use, leaves no mining legacies, has near-zero carbon footprint, and enables domestic supplies of CRM.
Although CRM are known to occur in geothermal fluids, there are still many uncertainties concerning their occurrence in different geological settings and the sustainability of their extraction. The actual extraction process is also a major challenge, requiring technology development. Hence, the project has the following objectives:
- Establish an overview of the potential in geothermal fluids for a large range of CRM elements across the EU and third countries;
- Determine the source of selected CRM, their mobility and potential for sustained extraction from geothermal brines;
- Develop and optimise innovative extraction technologies for selected CRM from geothermal brines that can form a business case for new EU SMEs;
- Assess the environmental-social-economic viability and foster ethical sourcing of CRM;
- Demonstrate at a pilot site the extraction technology for at least one CRM at the scale of a miniplant and evaluate the total sustainability of the system.
The possibility to replace conventional mines with extraction of CRM from geothermal brines offers a path to a socially acceptable and environmentally friendly mining industry.