UK launches first geothermal power plant using Earth's capabilities deep underground

The United Kingdom is marking the launch of its first geothermal power plant, introducing a new form of renewable electricity that harnesses superheated water from deep beneath the ground.

The facility near Cornwall in the far south of the country was switched on this week after nearly two decades of development, a process that required Geothermal Engineering Ltd (GEL) to drill the deepest onshore well ever completed in the UK, according to British media reports.

Water extracted from deep underground—heated by surrounding rocks—will not only drive turbines capable of generating electricity for about 10,000 homes but will also supply the country’s first domestic source of lithium, a critical mineral widely used in green technologies.

The Earth naturally produces heat that can be captured by drilling below the surface to create a renewable and continuous energy supply for heating and electricity generation, a process known as Geothermal energy. Temperatures increase the deeper one drills. At relatively shallow depths, the heat can already be used to warm homes and businesses.

Although geothermal methods have been used in parts of the UK before, this project reaches far greater depths—almost 5 kilometers below the surface—where temperatures approach 200°C.

"You drill deep boreholes into the ground, and then fractures within the granite rock are used to circulate the water that pick up the heat [that is] used for electricity production," explained Dr Jon Gluyas Monaghan, head of geothermal at the British Geological Survey (BGS), speaking to the BBC. Granite is especially suited for this technology because it effectively stores and conducts the Earth’s heat.

The achievement marks the first time such a project has been completed in the UK, largely because drilling to such depths is technically complex and financially demanding. The development has cost roughly £50 million (about $66 million) so far, financed by private investors and support from the European Union.

Experts say geothermal power offers advantages that many other renewable sources lack, most notably its ability to deliver a constant and reliable energy supply. Unlike fossil fuels such as Natural gas and Oil, it is also less vulnerable to price volatility.

By Nazrin Sadigova