Geothermal Engineering Ltd (GEL), the company developing a deep geothermal electricity power plant at United Downs in Cornwall, says it has found extremely high levels of lithium in the waters extracted for the power plant. It says tests suggest it could produce 4,000 tonnes of lithium per year from sites it is planning by 2026.
The use of lithium is ramping up very fast, as it is used batteries for electric vehicles and other uses, and GEL says “The race is on to produce locally sourced, zero carbon lithium”. At the moment it is mined in South America and Australia and shipped to China for processing and has a high carbon footprint.
GEL says that with partners it has been trialling sustainable, zero carbon methods of removing lithium from the fluid, so far managing to achieve a 95% extraction rate.
Ryan Law, managing director of Geothermal Engineering Ltd said: “Deep geothermal heat and power are already set to help the world reach net zero targets. The addition of lithium production with no carbon footprint or environmental damage will help to drive more geothermal projects forward in the UK and offer more opportunities for green jobs.”
“If the UK is to reach the government target to produce only electric vehicles by 2035, we have to find more sustainable and geopolitically more reliable ways to deliver lithium batteries. Establishing meaningful onshore lithium production in the UK would also encourage a lithium-ion battery-based economy to develop in the UK and could attract further important inward investment opportunities for Cornwall and the Southwest.”
GEL recently announced that Heads of Terms have now been signed on four geothermal sites in Cornwall, each anticipated to deliver 5MW of power and 20 MW of heat. Lithium tests will be conducted at each of the new sites as drilling gets underway.
They could also run it through a membrane to generate electricity due to the high salt content of the water (higher than sea water) before extracting the lithium, see Salt Power
http://www.saltpower.net/
So co-generation – electrical power and
heat (for homes, business, etc. ) via District Heating network
then more electrical power generation via salt gradient
then lithium (and other rare earths) extraction