A pioneering project to produce power from hot rocks several kilometres under the ground in Cornwall will begin drilling early next year, if a multimillion-pound fundraising drive succeeds.
Abundance, a crowdfunding platform overseen by the main City regulator, will this week launch a bond to raise £5m for the UK’s first commercial geothermal power station, located near Redruth.
Iceland is the world leader in geothermal power, where deep holes are drilled to reach hot rocks, water is pumped down, heated and returned to the surface to generate electricity or provide heating.
Cornwall’s extensive granite means it has long been seen as the most promising part of the UK for the technology, which one study found could provide a fifth of the country’s power.
However, previous plans for geothermal plants in the county have faltered because of problems with financing and risk-averse investors.
The Eden Project, for example, has wanted to exploit the rocks beneath it since 2009, but failed to win European funding.
The £18m United Downs Deep Geothermal Power project near Redruth, by contrast, has already secured £13m in public funding, £10.6m from the European Regional Development Fund and £2.4m from Cornwall county council.
Ryan Law, managing director of Geothermal Engineering Ltd, the UK company behind the project, said: “The big problem is because nothing has been done in the UK before, it’s quite high risk. Finding funding for that risk is extremely difficult.”
Abundance is confident it will raise the final £5m needed, having raised £50m from individuals for renewable energy projects since it started five years ago, and £7m in the last two months alone.
Investors can expect a 12% return on the bond, which has an 18-month term, and will have their capital returned to them if the geothermal plan does not go ahead.
Bruce Davis, the investment platform’s managing director, said: “Geothermal technology is proven to work in Italy and Iceland but hasn’t so far been used in the UK to generate electricity. This is a groundbreaking project.”
Drilling should begin in the first quarter of 2018 and take around five months as Geothermal Engineering Ltd drill a well 2.5km down, followed by a second deeper one of 4.5km, creating a circuit for water to be pumped down the shorter well and return up the other.
If all goes as planned, the Redruth operation could be operational in 2020.
The amount of power the wells are expected to produce will be small, at a capacity of 1-3 megawatts (enough to power 1,500-4,500 homes), similar to a single onshore wind turbine, but geothermal has one big advantage: unlike wind and solar, it can provide constant power if needed, like a nuclear power station.
Chris Goodall, an energy expert and author, said that geothermal would add to the rich renewable energy resources that the county already enjoys. “Energy independence for Cornwall is a realistic, cost-effective objective for the county council. This is a first-rate project,” he said.
Perhaps most importantly, the the project, if successful, could pave the way for geothermal power finally taking off across Cornwall.
Tony Batchelor, known as the grandfather of geothermal in Cornwall for his test research and drilling in the county during the 1970s and 1980s, told the Guardian: “This £18m is basically our chip in the game. Then we look at delivering bigger and better projects.”
Ultimately, geothermal could provide as much as 1,000 megawatts of capacity, said Batchelor, an adviser to Geothermal Engineering Ltd and chairman of Earth sciences consultancy Geoscience. While not a huge amount nationally, it would be significant for Cornwall.
“It’s great that geothermal in Cornwall can at last get going,” a spokesman for the Eden Project said of the United Downs project.
Previous efforts by the council and the Department for Communities and Local Government had put in place the conditions for several Cornish geothermal plants, the visitor attraction said. Eden said that several plants would “greatly reduce risk” and added that it hoped to make an announcement of its own within two months.
However, Goodall cautioned that this latest effort at making geothermal work in Cornwall was by no means guaranteed.
“Pretty much everyone agrees there is a lot of heat down there. But one of the reasons projects have struggled to get funding is that it’s highly fractured and it’s not a given [that it will work]. No one has yet been prepared to put in the highly risky capital to do this,” he said.
Bob Egerton, a Cornwall councillor, said he was sceptical about how big the resource actually was – but it was important to try to exploit it.
“It is a bit of a gamble, but ultimately we hope it will pay off,” he said. “The more we can produce from these sort of resources rather than hydrocarbons has got to be a good thing.”