Monday, November 9, 2009 - 11:10

EGS Energy Limited and the Eden Project on Friday unveiled plans for a £20 million engineered geothermal system (EGS) power plant on Eden’s site at Bodelva, near St Austell, Cornwall.

Eden’s partnership with EGS Energy, a privately-owned company based in Penzance, is to establish a plant to supply Eden with the electricity and heat to power its site, plus as many as 4,000 households. Any excess power could go on to the National Grid.

A well-attended meeting at Eden's Visitor Centre heard how technical expertise developed at the Hot Rocks geothermal plant at Rosemanowes Quarry near Penryn, Cornwall, from the 1970s to 1991 has been refined in France and Germany. This expertise is now ready to be tried and deployed at Eden in what could be the UK's first EGS plant providing electricity and heat.

An audience of around 150, including leading members of Eden’s Neighbours’ Forum, heard Eden chief executive Tim Smit describe how the earlier geothermal research project at Rosemanowes Hot Rocks project was held up as the “Holy Grail of renewable energy”.

The baseline scientific understanding and engineering skills achieved there had made the Eden EGS plant project possible, and Eden had welcomed the approach of experts from EGS Energy involved in developing further the technology.

Details of the proposal were outlined by the leading geophysicist Roy Baria, EGS Energy's technical director, who was the deputy director of the Rosemanowes project before moving to lead the EU geothermal programme at Soultz in France in 1990.

He said that Cornwall had the best potential to develop geothermal energy in the UK: “Engineered geothermal systems can supply power 24 hours a day. It is renewable and has virtually zero emissions. The footprint is quite small and there is virtually no impact on the environment. This resource that we see has the potential, if fully exploited, to supply ten per cent of the UK’s electricity for 200 years. We are focused on an environmentally friendly solution and it is a pleasure to work with the Eden Project who we see as an ideal partner.”

Dr Joerg Baumgaertner, EGS Energy’s special adviser operations, is one of the managers of the Soultz project. He has been instrumental in developing the first commercial EGS power plant in the world, at Landau in Germany.

Tim German, head of the Low Carbon Cornwall Unit, also spoke at the meeting. He said that Cornwall had the best resources in the UK to develop geothermal power: “We have to consider our own self-sufficiency. Projects like this fit in to the new low carbon Cornwall. I think it is a fantastic project for Cornwall.”

The meeting was chaired by Catherine Mitchell, Professor of Energy Policy at the University of Exeter’s Cornwall Campus, who also conducted a lively question and answer session.

It followed a meeting about the plans for local councillors, planners and network managers. They were informed that with a capacity of 3MW electric and the ability to generate 85 per cent of the time, the Eden EGS plant should produce enough electricity to supply Eden and around four thousand households, as well as the heating for the Biomes and possibly some district heating.

The Eden EGS plant would be made up of two boreholes, driven around 4km into the granite beneath Eden; the rock at that depth is at about 150-160°C. Water injected down the first borehole will be returned to the surface at around 150°C via the second borehole. The superheated water will be used to generate electricity, and will then be returned to the injection borehole.

Construction of the Eden EGS plant will involve an area about the size of a rugby pitch, falling to about half that once fully operational. The buildings would be no more than 10m (30ft) tall. Unlike other sources of renewable energy, the plant would be able to run 24 hours a day for over 300 days a year.

Matt Hastings, Eden’s energy manager, said: “We had very positive feedback from local councillors and the evening presentation to the public provoked a lively debate.

“Generally the mood of the meeting was positive and we are now looking closely at feedback forms filled out by the audience to better gauge how the plans are perceived.

“It is hoped that power will be delivered from late 2012, but this depends on many factors: planning permission, drilling rig availability, drilling progress and so on.

“Now we will continue our work on the environmental statement with the hope of submitting a planning application in early 2010.”