Let’s start this article by examining exactly what is geothermal energy. Essentially, geothermal energy comes from the heat that the earth naturally produces. It is a clean and sustainable form of energy and is extracted from shallow ground all the way down to the point where magma is formed.
The temperature in shallow ground remains consistently between 10-16 degrees Celsius. This heat can be extracted using geothermal heat pumps and used to heat and cool buildings. Technologies are fast developing to maximise what we can do with geothermal heat.
In the UK, the country’s first geothermal electricity plant has just sprung into action. It is located in the United Downs Industrial Estate in Cornwall, in the south of the country and is expected to provide sufficient energy to power 3,000 homes according to Geothermal Engineering Ltd.
Geothermal has received accolades by those in the know, including the US Department of Energy, which claimed that geothermal power is a vital and clean energy resource. It went on to sing its praises further by explaining that one of the key elements that makes this energy source so promising is its ability to supply power 24/7 without emitting any greenhouse gases.
Currently, geothermal energy is responsible for a mere 0.4% of the energy mix in the United States. However, with more and more research being undertaken in this area, there is little doubt that the US and other countries will try to increase this percentage in the coming years. The UK has already taken its first step to introducing geothermal energy.
Down in Cornwall, there are plans for two geothermal wells, which will be drilled into granite rock. The deeper of the two will plunge a staggering 4.5km below the surface of the earth. Water will be extracted from the deeper well and will emerge at a temperature of approximately 190 degrees Celsius. This water will then be fed through a heat exchanger when it reaches the surface in order to extract the heat from the water. Then, it will be sent back into the ground where it will heat back up again. This will work in a continuous cycle and the heat that is extracted will be converted into electricity and transmitted to the National Grid.
The managing director of Geothermal Engineering Ltd has high hopes for the geothermal sector in the UK. He explains that the geothermal resources in the country remain largely untapped and that they have the potential to provide up to 20% of the country’s electricity and heat energy in a sustainable and reliable way.
As coal plants are rapidly closing, more energy is needed from somewhere and geothermal seems as good a source as any from which to extract it.
The geothermal plant in Cornwall has received around £18 million in funding from a range of sources, including over £10 million from the European Regional Development Fund. Other sponsors include the British Geological Survey, GeoScience Ltd and the University of Plymouth Sustainable Earth Institute.
There is no doubt that the earth has to reform its energy consumption habits and it needs to do so fast. Tapping into yet another clean and sustainable energy resource is excellent news for anyone concerned with the future of our planet as it takes us one step closer to an emissions free future.