“Hot rocks” research comes to fruition with Britain’s first deep geothermal power station

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Planning permission for Britain’s first deep geothermal power stationwas granted by Cornwall Council this month.

Twenty five years ago, the idea of producing renewable energy from hot rocks deep underground was an enticing prospect but unproven commercially.Today, after decades of research, advances in technology and support from engineering and environmental consultancy Wardell Armstrong, it’s set to become reality with the go-ahead given for Britain’s first deep geothermal power station.

Geothermal Engineering Ltd is to create a 10 megawatt geothermal power plant at United Downs near Redruth, Cornwall. The plant will generate sustainable electricity by drilling to approximately 4.5 kilometres underground and tapping the geothermal heat. The wells will be the deepest onshore wells in Britain. As a by-product, the plant will also be able to export up to approximately 50 megawatts of hot water for renewable heating.

Planning permission for the project was granted by Cornwall Council this month. Wardell Armstrong played a key role in formulating and supporting the planning application, including carrying out the environmental impact assessment and a seismic hazard assessment.

Although local reaction has been generally very positive, a prime concern was to ensure that the noise involved in drilling would be at an acceptable level and within prescribed environmental health limits. Detailed noise modelling was used, as well as demonstrations with a noise meter as part of the public consultation exercise.

Seismic risk assessment was also necessary in the light of the new technology being applied. Unlike earlier unsuccessful attempts to create electricity by artificially creating a fractured rock reservoir deep underground, the approach taken by Geothermal Engineering Ltd involves drilling into pre-existing natural geological structures. Professor Julian Bommer from Imperial College, London, and Professor Bob Pine from the Camborne School of Mines (part of University of Exeter) were both involved in this highly specialised assessment.

The Geothermal Engineering plant will produce enough sustainable electricity to power nearly 10,000 houses, as well as being able to supply significant amounts of hot water for district heating and industrial uses.

Haydn Scholes, now director of renewable energy for Wardell Armstrong, was involved in the original 1980s “Hot Rocks” geothermal research project in Cornwall. “This is a very welcome advance.” he said, “It’s taken a long time to get here but it’s so good to see the efforts of so many people come to fruition.”, “Hopefully this will be the first of many and once again will put Cornwall at the leading edge of renewable energy developments in the UK”.

Ryan Law, managing director of Geothermal Engineering Ltd, said: “Decades of research have proved that Cornwall is a suitable location for deep geothermal plants. Combined with Government financial stimuli in the form of the Deep Geothermal Challenge Fund and the Renewable Heat Incentive, we’re seeing a real shift towards a renewable economy with the associated knowledge base and jobs that it will bring.”

About Wardell Armstrong Wardell Armstrong (www.wardell-armstrong.com) is a leading independent engineering consultancy specialising in environmental development and management. With a strong heritage dating back more than 170 years, the firm is today helping to tackle some of the world’s most pressing environmental challenges like renewable energy generation, waste management and environmentally responsible mining.

Wardell Armstrong provides wide-ranging renewable energy experience – covering wind, biomass, waste to energy, geothermal, hydro, wave, tidal and solar energy projects. Wardell Armstrong supports local and regional government organisations that need assistance with their sustainable energy strategies and carbon management plans. The firm also offers advice and practical support to utility companies, energy project and land developers, landowners, venture capitalists, smaller businesses and farm scale operations.

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  1. Would like to know what kind of rocks were they drilling to? How do they know what they are? Porosity,conduction,water. Or dry with fracking? Hotter than normal geothermal gradient? If so how did you know?

    To much of an ad and not enough meat.

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