The UK’s geothermal energy potential has received a massive boost thanks to some rocks in Cornwall. A £1.8 million research project undertaken by the British Geological Survey has identified huge geothermal energy potential in Cornish granite.
The organisation believes that the special type of Cornish granite has the highest subsurface heat flow of any UK rock-type. This means it can create the highest temperatures at deep levels underground, ideal for geothermal energy projects.
How Geothermal Energy Technology Works
To generate energy from geothermal technology, you must dig a couple of deep geothermal wells, usually a few kilometres deep. This is achieved by drilling into the rock beneath the site where suitable rock has been identified. For the current level of geothermal technology, one well must be significantly deeper than the other.
Once both deep wells have been excavated, water is pumped up from the deepest well. This is then piped through a heat exchanger at ground level and then piped back into the other well. This continuous cycle enables the water to pick up more heat from the rocks it is pumped passed. The generated heat is then extracted and converted into electricity which will most likely be supplied to National Grid.
Geothermal Energy has the ‘Potential to Progress’
The research project that identified the potential of Cornish granite is named ‘Geothermal Power Generated from UK Granites’. Thankfully it is nicknamed ‘GWatt’ for short. The GWatt project is funded by the Natural Environment Research Council (NERC) and should be completed within the next three years.
Those involved with GWatt are scientists from the Camborne School of Mines at Exeter University and Edinburgh-based Heriot-Watt University. The latter’s Chief Scientist, Professor John Underhill, said there is a need to address the UK’s carbon emission targets. He also believes that such targets and overall decarbonisation of the energy system represent a ‘major challenge’ for the UK.
Professor Underhill added, “Geothermal energy has the potential to progress both aspirations [current carbon emission targets and decarbonisation of the energy system in general] and the GWatt project will provide the means by which to test whether hot Cornish rocks will form part of the wider energy mix.”
Geothermal Drilling Projects Underway
The project also features contributors from GeoScience, Computer Modelling Group and the Cornwall and Isles of Scilly Local Enterprise Partnership. Another contributing partner, Geothermal Engineering Limited, already commenced one such deep drilling process towards the end of 2018.
They began drilling deep holes at the United Downs Industrial Estate near St. Day in Cornwall. The deepest well will reach 4.5 kilometres down into the earth. When completed it should generate enough to power around 3,000 homes, which is about 3 megawatts of electricity.
If you are interested in eco-friendly renewable energy generation then email Caplor Energy or call 01432 860644. Caplor are award-winning experts in the design, installation and maintenance of renewable energy systems.