The Eden Project in Cornwall will become the first place in Britain to be powered by geothermal energy as part of a wider scheme launched this week.
The pioneering project will see two boreholes drilled around two and a half miles below the ground to tap into the heat contained in the granite outcrops found there. These hot rocks are relatively close to the surface in Cornwall, making it an ideal location.
If planning permission is granted for the proposals, the £15 million power plant will be constructed within the same site as the Eden Project centre. It is hoped that it will be ready by 2012.
Water will be pumped down one hole and heated as it moves through the porous rock at the bottom before being pumped back up the other. It will return to the surface under pressure and at temperatures of around 150 degreees Celcius, where the heat will be converted into electricity.
Spare heat in the water could be utilised to heat local buildings or to grow exotic produce at Eden out of season.
Eden and its commercial partner EGS Energy estimate that the plant will produce up to 3MW of electricity – equivalent to powering nearly 5,000 homes. In comparison, the average wind turbine will generate up to 2MW, but only in the right weather conditions. Energy beyond the requirements of the Eden Project itself could potentially be sold to the National Grid.
Matt Hastings, Eden’s Energy Manager, said: “It’s a massively exciting project – a way of making sure Eden has a source of green power but also of feeding heat and power into the local community and into the National Grid. We will only need a quarter or a fifth of the electricity that will be generated. Cornwall leads the way in wind and wave energy technology. Now we're trying to do the same in geothermal power.”
Roy Baria, Technical Director of EGS Energy, stated: “With the geology in the vicinity of the Eden Project being ideal for creating our power plant and its reservoir, we would not only expect to be able to supply virtually all of the Eden Project’s power and heat requirements but generate surplus power that could be fed into the grid to help meet the Government’s CO2 reduction and renewable generation targets.”
Secretary of State for Energy and Climate Change Ed Miliband attended the launch of the pilot project, and the Government will be monitoring its progress for signs of its potential on a much larger scale. Experts believe there is enough energy contained in the granite beneath Cornwall to provide 10 percent of the UK’s electricity.
Germany has already built a geothermal plant and scientists across the globe are also looking at ways to harness the power from the Earth’s natural hot rocks.