Critical Raw Materials

CRM-geothermal is a research project funded by the Horizon Europe with the aim of combining the extraction of mineral raw materials and geothermal heat, a renewable energy resource from right beneath our feet that is always on and always available.

A large amount of mineral raw materials are needed in the energy and digital transitions, some of which are considered ‘critical’ by the European Union and the UK. Most of these Critical Raw Materials (CRM) are imported from non-European countries where environmental and ethical standards may be less strict than in the EU and the UK. The EU and UK has largely untapped resources at its disposal in geothermal fluids, some of which contain significant amounts of CRMs.

Graphic: 'Leonnidas'

The technology solutions developed by CRM-geothermal will help Europe and the UK achieve the strategic objectives of the EU Green Deal and the Agenda for Sustainable Development as well as reducing dependency on imported CRM.

The objectives of CRM-geothermal are:

  • To get an overview of the raw materials potential for a wide range of CRM elements across the EU and third countries such as the UK

  • To find and verify sources of selected CRM, their mobility and the potential for sustainable extraction from geothermal fluids

  • To develop and optimize new extraction technologies for specific CRM from geothermal fluids that can form a business case for new EU and UK SMEs

  • To ensure the sourcing of CRM is ethical, transparent, traceable and environmentally, socially and economically viable

  • To demonstrate extraction technology for at least one CRM at the scale of a pilot mini-plant and evaluate the system’s sustainability

The objectives of CRM-geothermal are:

Combined extraction will be cheaper and better for communities due to the potential to cover a major percentage of current and future demand.

Having a domestic and more resilient CRM supply chain by reducing imports shores up the market and reduces political risks.

More trustworthy and ethical supply chains for CRM.

A better understanding of societal resistance to extraction and increasing demand for materials by society.

Overseas suppliers will be encouraged to move towards more ethically acceptable production of CRM.

More geothermal projects (with combined extraction) will speed up the energy transition.

Graphic: ‘Leonnidas’

Cornish Lithium are running the fluid testing for CRM at United Downs

When will the testwork be taking place?

The testwork is taking place during the months of June and July 2023. The drilling rig required for equipment deployment is arriving on the 13th of June. The drill rig will be used to deploy the equipment into the existing borehole drilled in 2019, and no other drilling will be taking place, only testwork. The work will be permitted by Cornwall council under a General Permitted Development Order (GPDO) and the Environment Agency.

The GPDO application number is PA23/03827

Where will the testing be happening?

The sampling and testwork being hosted at two boreholes that have been previously drilled by Cornish Lithium, one near United Downs and the other within the Cornish Lithium site on the United Downs Industrial Estate.

What test work is being undertaken?

The testwork will be a combination of hydrogeological testing and geochemical sampling of the fluids. To characterise the fluids for CRM contents samples will be taken and analysed for their chemical constituents. Hydrogeological testing comprises of several stages of pumping the borehole and injecting fluid through specially engineered tools that can isolate the geological structure of interest. No further drilling will take place.

Why this testwork is needed?

Understanding the reservoir properties of the geothermal fluids that naturally flow deep underground is required for the potential future hosting of a demonstration extraction plant at United Downs. Part of the larger CRM project is that Cornwall will host this pilot plant to trial extraction technologies currently being developed by other project partners.

CRM members involved

Several members of the larger project team will be undertaking the testwork. This will include the British Geological Survey, GFZ (Helmholtz Centre, Potsdam), and Cornish Lithium (CL) who will be overseeing the test work. The drilling contractor that will be operating the work-over rig will be Priority Drilling Limited, who have drilled three other boreholes for CL previously.

The primary objectives for the testing at United Downs
  • Recharacterise the geochemistry within the permeable structures.
  • Confirm that maximum flowrates of boreholes given current borehole configuration.
  • Undertake cross-well monitoring between the boreholes during flow rate tests.
  • Determine aquifer properties and permeable structure continuity.
  • Characterise hydraulic conditions.
 Airlift testing and tracer testing

Airlift testing will allow us to gain more reliable hydraulic testing and flow rates. It involves isolating the permeable structures and using air pressure to bring fluid to the surface of the borehole.

Tracer testing allows us to determine capacities and recharge mechanisms for the geothermal reservoirs. It involves the injections of an inert substance and deploying it through the packer system into the structure.

2019 drill rig at United Downs

Funded by the European Union. Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or CINEA. Neither the European Union nor the granting authority can be held responsible for them.

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