UK’s First Geothermal Power Plant Launches in Cornwall

News By Jake Scolding

UK’s First Geothermal Power Plant Launches in Cornwall, Delivering Renewable Energy and Zero‑Carbon Lithium

The UK’s first commercial geothermal power plant has officially gone live in Cornwall—marking a landmark moment not only for low‑carbon energy generation but also for domestic critical mineral production.

Geothermal Engineering Ltd (GEL) one of the project partners of the Critical Minerals Challenge Centre, has switched on its United Downs power station near Truro, becoming the first facility in the country to generate electricity from the Earth’s natural heat. The project’s launch represents nearly two decades of development, including the drilling of the deepest and hottest onshore well ever created in the UK at over 5 km.

A New, Constant Source of Renewable Power

The £50 million project taps into naturally fractured Cornish granite, where geothermal fluids reach temperatures close to 200°C. The geothermal fluid heats a secondary fluid in the binary power plant which turns to a vapour at a much lower temperature than water, this drives turbines to generate up to a consistent 3 MW of electricity—enough to power up to 10,000 homes through a Power Purchase Agreement (PPA) deal with Octopus Energy.

Unlike solar or wind, geothermal power offers continuous, 24/7 renewable electricity. GEL CEO Dr Ryan Law described the milestone as “a huge advancement for geothermal power in the UK,” emphasising its importance for energy security and price stability.

The British Geological Survey has called the launch a “major step forward”, noting that the UK holds significant untapped geothermal potential, though high drilling costs remain a barrier to wider deployment.

 

A Breakthrough for Domestic Lithium Supply

In addition to generating electricity, the United Downs geothermal wells produce hot, mineral‑rich fluids containing commercially significant concentrations of lithium carbonate. This offers the UK its first opportunity to develop a secure, domestic source of a critical mineral essential for electric vehicles and energy storage technologies.

Professor Frances Wall, Project Lead of the Critical Minerals Challenge Centre, emphasised the significance of this development when speaking on BBC Radio 4’s Today programme:

“Alongside the heat, what they’re doing is extracting fluids from 5 kilometres deep in the earth to bring up the heat. As those fluids come up they will also have some minerals in them. Here in Cornwall that water has extracted lithium from deep in the granite and by putting an extraction plant next to the power station then they can take out the lithium and sell that potentially for battery manufacturing in the UK.”

GEL expects to begin producing around 100 tonnes of zero‑carbon lithium carbonate annually, with plans to scale production to 18,000 tonnes per year as additional sites are developed. With UK lithium demand expected to rise dramatically over the next decade, the Cornwall project represents a major step toward a resilient, low‑carbon supply chain.

National Significance for Energy Security and Critical Minerals

Government leaders have welcomed the launch as a model for integrated clean energy and minerals strategy.

  • Chancellor Rachel Reeves called the project “a huge opportunity for Cornwall to unlock investment, drive economic growth, support jobs, and establish the region as a vital player in Britain’s energy security.”
  • Minister for Energy Security and Net Zero Dr Alan Whitehead emphasised that domestic lithium production will help power the next generation of British EVs.
  • Industry groups highlighted that geothermal heat extraction and critical minerals recovery are “naturally complementary” processes, improving project economics and strengthening UK mineral resilience.

Catalysing a New UK Geothermal Sector

GEL already has two further deep‑geothermal sites in the pipeline, expected to deliver an additional 10 MW of renewable electricity by 2030. The UK government recently appointed its first Geothermal Minister, signalling growing national interest.

Cornwall’s unique geology—with naturally permeable “crosscourse” faults and higher‑than‑average surface heat flow—makes it the most favourable region for deep geothermal development in Britain. But geothermal potential also exists in Scotland and the Northeast, where resources remain under‑explored.

Globally, investment in next‑generation geothermal has surged, driven partly by the energy demands of major tech companies such as Google, Meta, and Microsoft. As the UK seeks to scale its clean power capacity and secure critical mineral supply chains, the United Downs project provides a powerful demonstration of what deep geothermal can deliver.

A Double First for the UK

With United Downs now generating electricity and producing zero‑carbon lithium, the UK has entered a new phase of renewable energy innovation—where clean power and critical minerals can be sourced from the same local resource.

As GEL expands its operations, the project is expected to play an increasingly influential role in Britain’s journey toward net‑zero emissions, resilient supply chains, and energy independence.