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Durham Energy Institute
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Geothermal Energy

Durham University leads research into the potential for geothermal energy in the UK and abroad. The UK's geothermal resources are significant could supply heat to the UK for over a century. Our innovative research considers water in abandoned mines as a future low carbon heat source. 

We are working with key stakeholders regionally, nationally and internationally, including governments and companies in the Oil and Gas sector, to promote the development of geothermal infrastructure and increase the use of Geothermal heat for industrial and domestic heating. 

Our research in UK Parliament  

In 2019 Helen Goodman MP led a debate in Westminster on the use of abandoned mines for heat using evidence collected by Durham Energy Institute. This follows on from a study by Durham University on using mine water to heat homes in Spennymoor. This study found enough resource to heat a planned development of 200 homes.

DEI has also been working with stakeholders from across North East England to ensure Geothermal energy from mine water is included in regional plans and strategies and considered for new developments.

It is now incorporated as a key pillar in the North East Energy for Growth Strategy and Coal Authority has more geothermal projects in its pipeline for the region than any other region in the UK.

A source of clean renewable energy under our feet is a very exciting prospect, and it's all right here beneath Spennymoor. The research carried out by Durham Energy Institute is very important in helping us better understand this resource and the ways we can best make use of it for a greener, more prosperous County Durham. This research was a key source for me when I led a parliamentary debate on Geothermal Energy, and I'm proud to work alongside the Institute promoting the benefits of this untapped energy source.
Helen Goodman
Former MP Bishop Auckland

What is Geothermal Energy?

Geothermal energy comes from heat produced at the Earth’s core. It is normally associated with volcanic regions e.g. Iceland or New Zealand, but volcanoes are not essential for geothermal energy.

Away from volcanic regions, most countries can access geothermal albeit at lower temperatures. Temperature increases by 25-30°C with each km depth. This means that a well drilled to 2km would reach a temperature of 50-60°.

The key thing is finding water at depth that is essential for bringing heat to the surface heat to the surface. Durham University is researching the UK potential for geothermal energy to decarbonise heat.

Where is geothermal heat located?

The UK has a range of geothermal settings:

Deeper than 1km, temperature 35°C or more

  • Sedimentary basins
  • Radiothermal granites
  • Buried cave (karst) formations
  • Onshore and offshore hydrocarbon wells

Shallower than 1km

  • Flooded abandoned mines 12-20°C

Heat from abandoned mines

Abandoned mines across the UK are flooded with water that can be used to heat homes. Abandoned mines are shallower and cooler than deep geothermal systems. This means that development risks are significantly reduced because we know former mining infrastructure can flow water through existing tunnels and shafts.

The UK has 23,000 flooded abandoned coal mines and 25% of the built environment lies above abandoned coal mines. In addition to providing low carbon, secure energy this can bring economic and social improvements to regions that suffered following the abandonment of deep mining in the UK.

We are working with local authorities, local communities, Parliament, the Coal Authority and industry to explore options for geothermal energy in the North East of England, and to ensure Geothermal energy from mine water is included in regional plans and strategies and considered for new developments.

Geothermal mine water energy is now incorporated as a key pillar in the North East Energy for Growth Strategy, and the Coal Authority has more geothermal projects in its pipeline for the region than any other region in the UK.

DEI has been a central advocate for the geothermal potential of the region, and the opportunities this presents for our economy and to decarbonise heat, providing both the evidence base and enthusiasm to make sure this was a key theme in our Energy for Growth Strategy.
Andrew Clark
Energy Programme Lead at North East Local Enterprise Partnership

How much heat is down there?

The UK's geothermal resources could meet the UK heat demand for over a century. Using it will need changes to how we supply and use energy.

Existing buildings would change their heating systems to use geothermal energy. The UK has one proven deep geothermal energy system in Southampton.

Why aren't there more geothermal systems?

Risk is the biggest barrier to geothermal development. The technology exists to drill wells but it is difficult to predict how much water is present at depths of over 1km.

Abandoned mines are lower risk. Although they are shallower and cooler we know water can flow through tunnels and shafts. Abandoned mines are a good opportunity for UK geothermal because risk is reduced. Also, it uses existing infrastructure that people worked hard to create.

Further Information and Resources