An investment from the European Regional Development Fund (ERDF) worth up to £10.6m will enable a revolutionary geothermal venture at United Downs to move forward.

The United Downs Deep Geothermal Power project, which is the first of its kind in the UK, will explore the geothermal resources at depth and hopes to use the energy to drive a demonstration power plant supplying electricity to the local grid. This project will be led by Geothermal Engineering Limited (GEL).

The granite that lies beneath Cornwall is heat-producing and the rocks here are hotter than anywhere else in the UK, making it the best place to extract energy for both heat and power. To unlock the potential at United Downs two boreholes, or "wells" will be drilled, one 2.5km deep and the other 4.5km deep. The deeper of the two wells would be the deepest onshore hole in the UK.

Water will be circulated between the wells, collecting heat from the rocks, before being brought to surface at a temperature of about 1,750C and being fed into the demonstration power plant. The plant will generate 1MW of clean renewable electricity, which is enough to meet the electricity needs of about 1,500 households.

GEL project manager Peter Ledingham, a graduate of the Camborne School of Mines, said: “Cornwall has the best geothermal resources in the country but we have yet to press home our competitive advantage. By drilling and testing the deep wells at United downs we hope to prove the quality of the resource and demonstrate the viability of generating renewable electricity from it.

"The project therefore offers significant potential for economic growth in Cornwall and Isles of Scilly, building on its reputation as a ‘green and marine’ region.”

Julian German, deputy leader of Cornwall Council, said: “I am very excited about this announcement. This is a great opportunity to utilise the unique geology we have in Cornwall and presents a chance to lead a new emerging sector. Deep geothermal heat and energy could be a game changer for energy costs to both residents and businesses and help us eliminate fuel poverty in Cornwall."

Mark Kaczmarek, Cornwall councillor for Carharrack, Gwennap and St Day, added: “My working background is in mining here in Cornwall and I have first-hand knowledge of how hot some places can be at depth. This is great news and a very exciting project for United Downs Gwennap and will be the first of its kind in the UK supporting skilled employment.

"This will once again put Cornwall on the map of innovation. If successful, the geothermal energy produced could supply a significant amount of renewable energy for local residents and businesses and will be an asset for the local area.”

The drilling will begin in early 2018 and take about six months. Testing the wells, characterising the geothermal system and installing the power plant will take a further 18 months, with a target commissioning date in early 2020. If this pilot project is a success, it will be a catalyst for further investment in Cornwall and the Isles of Scilly with the potential to develop a new geothermal industry in the county.