Cheap power under our feet

“UK borrows Iceland’s geothermal techniques to tap the heat at the centre of the Earth to solve our energy woes“

And yet geothermal has proven remarkably resistant to exploitation.

Hot rocks technology, which uses the heat of the Earth’s core to generate power, will soon become a reality in Britain. Plans have been unveiled to tap into geothermal resources at five sites, including one in Manchester with the potential to heat 7m homes. And planning permission has been granted to two projects in Cornwall, considered to be the leading county in hot rocks technology, including a £32m scheme at the Eden Project.

Ministers have struck a deal with their Icelandic counterparts to share technical advice, drawing on their experience in capturing the power of their geysers. Supporters of the technology are increasingly confident that reforms to renewable energy subsidies will make more projects commercially viable.

The technology is surprisingly simple. Water is either pumped into the ground, or drawn from a deep well, and pumped back to the surface, where it is used to heat homes directly or to produce steam to drive a turbine that generates electricity.

A study by Sinclair Knight Merz, engineering consultants, found deep geothermal resources could provide 9.5 gigawatts (GW) of renewable electricity, equivalent to almost nine nuclear power stations and 20 per cent of the UK’s electricity demand. It could also provide more than 100GW of heat, enough to meet the UK’s entire demand for heating homes and buildings.

Hotspots are spread across the UK, but they are more likely to be found in the Lake District, Yorkshire, Lincolnshire, Cheshire, Dorset and Hampshire. Parts of Scotland and Northern Ireland are also considered promising.

To date only one geothermal heat plant, in Southampton, exists. But developers believe they are close to a major technological breakthrough that will make it commercially viable and a source of green energy.

Independent