Heat from miles underground to power 10,000 homes in UK renewable energy first

The UK's first deep geothermal plant that produces power from heat miles underground and lithium for batteries is being switched on in Cornwall.

Geothermal Engineering Ltd's (GEL) £50m United Downs site will deliver renewable electricity around the clock, generated from the country's deepest well ever drilled, at more than three miles (5km) below the surface. The site will draw up water at extremely high temperatures of more than 190C to drive turbines that will generate power for 10,000 homes.

The water contains a high concentration of lithium, which will be extracted to produce zero-carbon lithium carbonate, which can be used in the production of electric car batteries. GEL said it will produce 100 tonnes of lithium carbonate annually starting from this year - enough to make 2,500 car batteries.

The company said on its website: "Geothermal energy is a form of renewable energy derived from the Earth's natural heat; the term 'geothermal' literally meaning 'heat from the Earth'. "In Cornwall, natural fractures or faults in the rock, known locally as crosscourses, act as reservoirs for hot water within the granite.

The naturally high temperatures found in the granite are ideal for geothermal energy production." Ryan Law, GEL's chief executive and founder, said there were plans to expand the site and develop two other geothermal energy projects in Cornwall, with the potential to produce enough lithium for 250,000 cars a year. The first site will produce three megawatts of power, with the three projects generating up to 10 megawatts of power, GEL said.

Octopus Energy has signed a long-term deal to purchase at least three megawatts of electricity, powering 10,000 homes. Dr Law said there was potential to expand geothermal energy across the UK to generate large amounts of renewable power.

"We're effectively tapping into a massive nuclear power station that someone's already built," he said. "The resource is gigantic," he added.

Dr Law said while the plan to produce deep geothermal electricity in Cornwall had been years in development, the company had not planned to produce lithium, it was "just lucky". "When we tested the water in these very deep wells, we found it is full of lithium," he said.

"It's a very high concentration of lithium and it's a very clean fluid, so it's a natural thing to do as a by-product from the power." Read more from Sky News:Energy price cap to fall in AprilTemperatures to drop after hottest day of year Dr Law said the plant generates power to process the lithium, while the electricity generation process also cools the temperature of the liquid down to a level to be able to extract the mineral. He said the production of critical minerals needed to be scaled up in Europe, to reduce reliance on imports from other countries, such as China.

Energy minister Alan Whitehead said: "The UK's first ever geothermal power is a ground-breaking moment for UK energy innovation, powering thousands of homes with clean, homegrown power.".