A PIONEERING environmental project to produce "the holy grail" of renewable energy in Cornwall is being launched.

The UK's first geothermal power plant – which will be built at the Eden Project if plans are successful – could revolutionise energy production by supplying a "secure, consistent and carbon-neutral source of heat and power".

EGS Energy and Eden believe the vast quantity of geothermal energy stored in the rocks below Cornwall could eventually provide up to 10 per cent of the UK's entire electricity requirements.

Geothermal energy uses water heated deep underground and pumped back to the surface to drive a power station and produce carbon-neutral energy.

This source of energy has been researched in the South West for decades, but now experts insist a Cornish plant is commercially viable and point to the success of a site run by a sister company in Germany.

A spokesman for EGS Energy said: "This could open up the holy grail of renewable energy – a secure, consistent carbon neutral source of both heat and power. The energy would be 100 per cent controllable and on an industrial scale.

"Above all, compared to other clean technologies, it has a small footprint above ground."

The groundbreaking 21st-century scheme would harvest the natural resources below the surface in a poignant echo of Cornwall's magnificent mining history.

The power plant at Eden would consist of a two-borehole system, both around 3-4km deep. Water would be circulated between the bottoms of the two wells, with it being heated by the hot rocks deep underground and returning to the surface at approximately 150 degrees Celsius. There it would drive a binary turbine to create electricity.

Roy Baria, technical director of EGS Energy, was deputy project director at the Rosemanowes Hot Rocks project in Cornwall, the UK's pioneering deep geothermal programme in the 1970s and 80s and worked as chief scientist of the European EGS geothermal programme in France until 2005.

He said: "We are lucky to have found in the Eden Project the perfect partner to take engineered geothermal systems to commercial reality from academic exercise, here in the UK where many of the skills that we bring to bear originated.

"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 carbon dioxide reduction and renewable generation targets."

Different locations within Eden are being looked at as possible sites for the plant. Subject to planning permission and funding, it is expected the project could be completed, the boreholes drilled and the power plant producing power by 2012.

Guy Macpherson-Grant, managing director of EGS Energy, said the cost of the project would be in the region of £15-20 million made up of a combination of private investment and public funding.

One of EGS Energy's partners, BESTEC GmbH, now operates a commercial plant in Landau, Germany.

Mr MacPherson-Grant said the time was right to launch a commercial geothermal plant after decades of research.

Staff at the Eden Project are filled with optimism over the possibility of providing clean energy from the site near St Austell.

Engineer Matt Hastings said: "It's massively exciting to be involved in what could be the resurgence of geothermal energy.

"Landau is the first commercially viable system in Europe. I've been there and it's incredible to see how low-impact it is."