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Artist's impression of Eden's Geothermal Energy Project

Eden Geothermal Energy Project

Eden Project is a partner on a groundbreaking geothermal energy project right here on our site, to harness naturally occurring sustainable energy from the rock deep underground.

Why geothermal is so groundbreaking

What we're doing

Eden Geothermal logo

In partnership with EGS Energy and Bestec UK, we've set up a new company – Eden Geothermal Ltd – to build a geothermal plant on the Eden Project site, using the heat from the granite underground.

We’re working on the basis of the power plant producing all the heat and power Eden needs plus enough electricity for the equivalent of up to 7000 homes.

On a site the size of a football pitch close to the main gate, we have drilled a single well 4.9km deep into the rock. This first phase of the geothermal plant will produce enough heat for Eden’s Biomes, offices and nursery greenhouses.  

Its success will pave the way for a second well and electricity plant, so that by 2025 Eden should be exporting enough renewable electricity and heat to wipe out its carbon footprint.

The £16.8m project has been funded by the European Union, Cornwall Council and an institutional investor.  

How deep are we drilling?

What is geothermal energy?

Did you know?

The 4.9km is only 25cm wide – that’s the size of a pizza!

Geothermal energy is the heat in the rock beneath our feet. Worldwide, natural spas have been enjoyed for millennia, and in active volcanic and tectonic areas, like Italy, hot rocks have been producing power for a hundred years.

Advances in engineering mean that lower temperature resources in geologically stable regions are now usable.

When we have completed the second phase, the power plant at the north end of our site would be an 'engineered geothermal system' (EGS). See how they work, below.

Diagram explaining how geothermal works

How geothermal works

In construction

Two boreholes, each around 25cm wide, are drilled into the rock to a depth of about 4.5km. Water is pumped down one borehole into the natural fractures in the rock to create an engineered heat exchanger between the two boreholes.

In operation

Cold water is injected down one borehole, picks up heat from the rock and is pumped back up to the surface at about 180°C.

This hot water runs through a binary cycle turbine to make electricity.

What's so good about geothermal?

  • Geothermal power is the only renewable energy resource not affected by the weather; it is 'on' 24 hours a day, with plants typically running over 90% of the time.
  • The surface area of the plant is the smallest of any power source, and with buildings no higher than 10m, geothermal energy has a low impact on the landscape.
  • It's estimated that geothermal could provide 20% of the UK’s electricity needs, but this is in addition to a vast amount of heat – perhaps even all the heat the UK needs. At present, there aren’t any geothermal power plants generating electricity in the UK.

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Drilling at Eden's geothermal energy site

Gus Grand, Executive Director, Eden Geothermal Ltd

“If we can begin a [geothermal] industry here that learns how to drill cheaper and quicker, and bring costs down, the renewable problem is solved.”

Dig deeper into Eden Geothermal

Funders and delivery partners

Eden Geothermal is being part-funded by the European Regional Development Fund and Cornwall Council with commercial funding from Gravis Capital Management through GCP Infra. Eden Geothermal is working with a number of delivery partners: Eden Project, EGS Energy, Bestec UK, and the University of Exeter.

European Union – European Regional Development Fund logo
HM Government logo
Cornwall Council logo
Gravis logo
Eden Project logo
EGS Energy logo
Bestec UK logo
University of Exeter logo