Successful drilling at UK’s first deep geothermal plant in Cornwall

11th September 2019 | Commercial Energy

Drilling to establish the UK’s first deep geothermal electricity plant has been successfully completed at United Downs Industrial Park in Redruth, Cornwall. Geothermal Engineering Limited (GEL) has established the deepest well every drilled on UK soil, at circa 5.1km vertical depth.

The well is also the hottest, with temperatures of approximately 195C. Initial water flow tests suggest that the project will be capable of producing the UK’s first geothermal electricity. Further testing is now underway.

Geothermal Plant

To establish the United Downs power plant, two deep geothermal wells have been drilled into the granitic rock beneath the site. The wells are directions (j-shaped) to intercept a target geological structure (the Porthtowan Fault). The natural structure enables water to be circulated through the hot rock from the injection well to the production well in a continuous cycle. As the water moves through the rock it picks up heat which is then extracted and converted to electricity at the surface.

The United Downs project was established by GEL to demonstrate the potential of the deep geothermal resource in the UK to produce both zero carbon electricity and heat. The United Downs plants is to supply up to 3MW of electricity, which is enough energy to power 3,000 homes. The electricity and heat energy produced from the plant will be continuous (24/7) as geothermal energy does not suffer from the peaks and troughs that many other renewable power sources are subject to.

Dr Ryan Law, Managing Director of Geothermal Engineering Ltd, said, “We are delighted to have completed the drilling of these technically challenging wells. Reaching our target at the Porthtowan Fault Zone, at such a depth, was a fantastic achievement in geological and engineering terms and the initial flow test are very exciting for unlocking the potential of the granite in Cornwall.”

More information available on the website below