A new assessment by the British Geological Survey has quantified the geothermal resource beneath the UK: enough heat to power the nation for centuries. The catch? Extracting it costs more than fossil fuels, at least for now.
The report, published today, estimates that deep geothermal energy could supply up to 20% of the UK’s heating demand by 2050, if investment in drilling and infrastructure accelerates. “The heat is there, but so is the price tag,” said Dr. Eleanor Finch, lead author.
“We’re talking about capital expenditure comparable to offshore wind, with a longer payback period.” Geothermal plants, which tap into hot rocks 3–5 km underground, produce baseload power with zero carbon emissions. However, drilling costs have remained stubbornly high, averaging £12 million per well.
The report notes that Cornish granite alone holds enough heat to generate 500 MW for 50 years. Yet without government subsidies or carbon pricing, developers shy away. The UK currently has one geothermal power station, in Cornwall, generating 3 MW.
Compare this to Iceland, where geothermal supplies 25% of national electricity and 90% of heating. “Iceland sits on a tectonic plate boundary; we do not,” Dr. Finch said.
“Our geology requires deeper, more expensive wells. But the heat is still there.” The report calls for a national drilling programme to de-risk the technology, similar to the early push for North Sea oil.
“We often hear about the energy transition as a problem of physics or engineering,” said Dr. Vance, commenting on the story. “But increasingly, it appears to be a problem of economics and political will.
The heat beneath our feet is abundant. The challenge is spending money to save the planet.” With the UK aiming to decarbonise heating by 2050, geothermal offers a firm, weather-independent source.
The question remains whether the nation is willing to pay the upfront cost to tap it.
