Lithium in Geothermal Waters
The granite rocks that underlie Cornwall are rich in lithium and heat. This means there is significant potential for lithium-enriched geothermal waters across the region. These waters can be accessed via boreholes drilled from the surface in to permeable geological faults at depth. Once the waters have been pumped to the surface, it is possible to selectively extract the lithium compounds using environmentally responsible Direct Lithium Extraction (DLE) technologies. By utilising geothermal energy to power this extraction, there is the opportunity to produce zero carbon lithium. Cornish Lithium aims to produce battery quality zero carbon lithium chemicals directly from the geothermal waters.
Lithium was first discovered in ‘hot springs’ in deep Cornish mines in 1864, by Professor Miller of King’s College in London. Historic records indicate the presence of such lithium-enriched geothermal waters across the whole of Cornwall, the most South Westerly county in the UK, where they circulate naturally within permeable geological structures. These highly permeable geological structures cut across the region and can penetrate to many kilometres deep. Cornish Lithium is evaluating the economic viability of extracting lithium from these waters through regional exploration and targeted drilling campaigns. There are two main opportunities within this work stream:
Lithium from ‘shallow’ geothermal waters (approximately 1-2km depth). These waters are warm and there is potential to use this heat energy to aid the lithium extraction process.
Read about our flagship United Downs project here.
Lithium from ‘deep’ geothermal waters (depths of over 5km). Deeper waters are significantly hotter than at a shallower depth, which means there is potential for the geothermal waters to be used to produce zero carbon electricity as well as heat. This electricity could be used to power a lithium extraction plant and enable lithium to be extracted from the same waters. Lithium produced in this manner has the potential to have a net zero carbon impact.
Read about the pilot lithium extraction plant that Cornish Lithium is building at the United Downs Deep Geothermal Project, in collaboration with Geothermal Engineering Limited through our joint venture GeoCubed.