Why geothermal energy?

By 2050, in the working life of anyone in their mid-thirties, greenhouse gas emissions in the UK will be net zero, and to achieve this, all electricity and heat will have to be as close to zero emissions as possible.

From a slow start, low carbon energy development in the UK has picked up in recent years, with a record 67 straight coal-free electricity days between April and June 2020. But it is a huge task to get to and stay at zero emissions, and concerns about the intermittency, visual intrusion and land take of renewables on one hand, and the cost and security issues around nuclear on the other, mean that new technologies are needed.

Geothermal energy is a renewable source of power and heat…

  • that runs 24 hours a day, whatever the weather,
  • on the smallest surface footprint of any energy source,
  • with no buildings higher than 10m,
  • that could supply the UK with 20% of its electricity needs,
  • and can help support the  electricity grid with despatchable power
Benefits of geothermal energy

Advantages of geothermal

  • Unlike other renewable electricity generators, geothermal plants are ‘on’ 24 hours a day, and have very little visual or surface impact. Geothermal power is permanently available and independent of the weather.
  • The technology relies on the heat from the earth, a virtually infinite resource, unlike fossil fuels. It does not rely upon the use or import of raw materials as for example biomass does. With no variable fuel costs or fuel supply issues, geothermal plants can be run at full tilt and have a typical capacity factor of more than 90% – i.e. they are in active use for almost all the time. 
  • With many people’s disquiet at the visual intrusion, expense and intermittency of other renewable resources on one hand, and dismay at the expense and security issues around nuclear development on the other, geothermal electricity offers an acceptable face of low-carbon energy development. 
  • As a distributed base load electricity generator, and with the potential to be used as a dispatchable load that can be ramped up and down at will, geothermal generators can help support the national grid and local distribution grids, a feature becoming ever more important with increasing numbers of solar and wind developments.
  • Geothermal generates both heat and power. The by-product heat can provide affordable heat to local heat networks, agriculture and industry, creating jobs and replacing imports with home-grown produce from geothermally heated green houses and fish farms. Geothermal heated spas and swimming pools for year round use can support tourism.
  • The development of the geothermal industry will produce a number of high value jobs, through direct employment and spin-off industries. Based on a study by the Geothermal Energy Association, 100MW of installed capacity should produce between 1400 and 1700 full-time high-quality jobs, and build academic and engineering excellence in the Universities of the region.
  • When Eden Project and EGS Energy took a geothermal exhibition to the Royal Cornwall Show in 2013, we asked the question ‘Do you support geothermal development in Cornwall?’ Over 99% of those who responded said ‘yes’.

Types of geothermal energy technologies