The UK's first deep geothermal power plant – capable of generating baseload electricity and extracting battery-grade lithium – has been switched on at United Downs near Redruth in Cornwall.

The £50m ($67.09m) facility, developed by Geothermal Engineering, draws superheated water exceeding 190°C from the UK’s deepest borehole more than 5km underground. The heat is used to drive turbines that generate 3MW of continuous electricity. Octopus Energy has signed a long-term agreement to deliver the plant’s output into the national grid.

High lithium concentrations discovered during water testing have enabled co-production of up to 100t of zero-carbon lithium carbonate annually for use in electric vehicle batteries. The electricity generation process cools the geothermal brine to optimal temperatures for lithium extraction.

The project highlights Cornwall’s granite geology and includes plans for site expansion, alongside two further developments targeting a combined 10MW of geothermal capacity and significantly increased lithium output.