Engineers connect UK’s first geothermal power plant to grid

We are supporting the development of pioneering renewable energy by connecting the UK’s first geothermal power plant to the grid.

The facility at the United Downs industrial site near Redruth is designed to generate power and heat from the naturally hot granite rocks deep beneath the Cornish landscape.

Operated by Geothermal Engineering Ltd (GEL), it will generate up to 3MW of electricity which will be enough to supply up to 10,000 homes.

At the heart of the power plant is the United Downs geothermal well, the hottest and deepest onshore well in the UK, reaching a depth of more than 5,000 metres.

Heat from deep within the granite is brought to the surface and used to produce renewable energy.

Our engineers modified an existing 33kV connection point that was no longer is use so the geothermal plant can now feed into Lanner primary substation and Rame bulk supply point substation. This required recommissioning the site and updated equipment to monitor voltages being exported to the grid from the plant.

Adrian Parker, NGED’s Major Projects Director, said: “By providing a connection to the electricity distribution network, we are playing a key role in enabling energy generated at United Downs to be exported and used locally.

“The project highlights how network infrastructure is evolving to accommodate emerging technologies and supporting the transition to cleaner sources of energy, while making use of Cornwall’s unique geological resources.”

As well as electricity, the geothermal plant will produce lithium from the mineral-rich water that is used in the power generation process.

Lithium is used to make rechargeable batteries for electric vehicles (EVs) and GEL predicts the plant will produce 10,000 tonnes annually by 2030, enough for around 250,000 EV batteries a year.