A quiet revolution is underway deep beneath our feet. The Earth’s crust, long dismissed as a marginal source of power, is now the arena for a 12 billion pound global race to unlock clean, baseload electricity. British companies are emerging as frontrunners, deploying advanced drilling technologies that could transform the energy landscape.
The concept is simple: tap into the planet’s internal heat by drilling several kilometres down, circulating water through hot rock, and using the resulting steam to drive turbines. Unlike solar or wind, geothermal provides continuous power, unaffected by weather or time of day. This baseload reliability, coupled with falling costs, has ignited a surge of investment.
According to the International Energy Agency, global geothermal capacity could reach 800 GW by 2050, up from 16 GW today. The UK’s Geological Survey estimates that deep geothermal could meet 20% of Britain’s electricity demand. But the real prize is not just electricity: direct heat for homes and industry, plus extraction of critical minerals like lithium from geothermal brines.
The technology is scaling rapidly. The key breakthrough is “enhanced geothermal systems”, or EGS, which use hydraulic fracturing to create permeability in hot dry rock. This expands the resource base from volcanic regions to any location with sufficiently hot rock at depth. Start-ups like Cornwall’s Geothermal Engineering Ltd. and Scotland’s Lease Geotechnical are drilling deeper and cheaper than ever before.
Investment figures are staggering. The UK government has allocated 30 million pounds for early-stage projects, while private capital is flowing in from pension funds and sovereign wealth funds. The 12 billion pound figure reflects planned spending across 15 major projects over the next decade, including three in the UK: the United Downs Deep Geothermal Power project in Cornwall, the Eden Project’s geothermal heating scheme, and a district heating network in Stoke-on-Trent.
But challenges remain. Drilling costs remain high, though they are falling by 15-20% per annum as rigs become more efficient. Seismic risk, though minimal compared to oil and gas fracking, requires careful management. Regulation is also catching up: the UK’s Oil and Gas Authority now licenses geothermal wells, and the government is consulting on a new regulatory framework.
The opportunity for the UK is clear. The country has a unique geological advantage: granite batholiths in Cornwall and Weardale, plus deep sedimentary basins under the North Sea that could be repurposed for geothermal. British firms have decades of experience in offshore drilling, and the supply chain for deep geothermal closely mirrors that of oil and gas. This creates a pathway for job transition as the world decarbonises.
Critics argue that geothermal will never compete with cheap solar and wind. But they miss the point: renewables need storage for 24/7 power, and battery costs are not falling as fast as projected. Geothermal offers a complementary solution, providing firm capacity that reduces the need for gas peaker plants.
The race is global. The United States, Iceland, Japan, Indonesia, and Kenya are all expanding. But the UK’s early mover advantage, combined with its world-class engineering and financial sector, positions it to export technology and expertise. Companies such as Cornish Lithium are also developing geothermal-lithium extraction, aiming to produce battery-grade lithium from geothermal brines by 2025.
If the UK scales its geothermal capacity to 10 GW by 2040, as some projections suggest, it would represent a seismic shift in the nation’s energy mix. The heat beneath our feet is not a marginal curiosity; it is a massive, baseload resource waiting to be harnessed. The drilling rigs are turning. The question is whether we can match the speed of the climate crisis with the pace of our ingenuity.
