UK's first deep geothermal plant starts Cornwall drilling

The rig on site at the United Downs Industrial Estate
Drilling has started this week near St Day in Cornwall to demonstrate the potential of the geothermal resource in the UK to produce electricity and renewable heat. The pioneering demonstration plant at the United Downs Industrial Estate will supply up to 3 MWe (Mega Watt electrical) of electricity, enough to power 3000 homes.

Two deep geothermal wells will be drilled into the granitic rock beneath the site, the deepest of which will reach 4.5km making it the deepest onshore borehole in the UK. Water will be pumped from the deepest well at a temperature of approximately 190°C and extracted heat will be converted into electricity and supplied to the National Grid.

The low carbon energy source does not suffer from peaks and troughs that many other sustainable power sources are subject to and it is hoped that this innovative approach will be replicated in other suitable sites in Cornwall and Devon. Dave Schofield, Director of Energy Systems and Basin Analysis at the British Geological Survey said 'Geothermal energy in the UK has the potential to significantly contribute towards reaching our CO2 emission target; the Cornish geothermal project has the potential not only to supply electricity and heat, but also to demonstrate technical and economic feasibility of this form of clean energy.'

The project has received around £18 million in funding, including £10.6 million from the European Regional Development Fund. The British Geological Survey is just one of the delivery partners in the project and is well placed to help provide good science to the United Downs programme and projects linked to it including microseismic monitoring as well as geochemistry and hydrochemistry analyses.

More information on geothermal energy


8 November 2018