Geothermal Energy Underexploited In UK Says Report

We’ve seen lively debates recently over the merits of solar power, wind turbines and tidal power in Scilly.

But one form of renewable energy seems to have been overlooked, even though one St Mary’s building has been using it for years.

A report by the Renewable Energy Association says the UK could generate up to a fifth of its power needs through the use of geothermal energy.

It states there are ‘hotspots’ dotted around the country, particularly in Cornwall, the Lake District, East Yorkshire, Lincolnshire and Cheshire. Areas with large granite deposits are known to have higher geothermal potential due to the retention of heat by the rocks.

But many people are unaware that our Islands’ Health Centre has been using geothermal energy to provide heating and hot water for years.

Dr Adrian Davis, who worked on the project team that built the centre in 1997, said they were keen to explore the use of renewable energy to reduce energy costs. He said they were lucky to have a visionary architect, Barry Briscoe from Cornwall, who suggested using a ground source heat pump to tap into the heat generated within the earth.

The system is composed of a long loop of tubing buried in the ground around the Health Centre. A fluid, similar to that in a fridge is pumped through and transfers heat from the ground to the building.

Adrian says it works “like an air conditioning unit in reverse.”

The big advantage is that there are no unsightly panels or turbines to spoil the building.

And while Adrian, who retired from the practice several years ago, says he doesn’t know the recent running costs, he says the system has been quietly ‘chugging away’ for years with minimal maintenance.

He said most people who work in the building have actually forgotten it’s there.

The Renewable Energy Association criticises the Government for failing to support the geothermal industry in the same way it has helped solar and wind generation and says we’re falling behind other countries such as Germany and Sweden.


One Response to Geothermal Energy Underexploited In UK Says Report

  1. Jonathan Smith June 11, 2012 at 3:56 pm

    This is very interesting and an area ISREC is very interested in. We’re hoping to do more investigative work later this year on geothermal.

    Recently Transition Penwith did an event on geothermal and here are some notes from it – hopefully they’re useful (sorry about long reply!).


    – you don’t have to go down very far before the rocks start getting very hot, particularly granite where radio-activity is leading to even greater heat than elsewhere in the UK

    – the process involves drilling two 4km holes not far from each other but both located over a known fault line in the granite. There are several well known fault lines running North-West to South-East across the south of Cornwall. One ran near Lands End but the map didn’t include the Scillies so although you’re made of granite you won’t necessarily have a fault line.

    – one such fault line runs under United Downs near Redruth where there also happens to be an industrial estate as well as convenient electricity grid connections so this is the proposed test site.

    – water will be pumped down one of the holes; make its way along the fault heating up in the process; rising to the surface via the other hole as steam; this will turn turbines and generate electricity; the cycle will then continue.

    – it’s a known technology which has been in use elsewhere (particularly California) for years

    – they need to raise another £3 million pounds before they can go ahead but one of the things that puts off investors is that you can’t currently purchase a licence to extract heat like you can to mine tin or anything else; it feels like nothing more can happen until this is possible.

    – if it does all work out then there could be numerous small scale geothermal plants with surface buildings not much more intrusive than a typical unit on an industrial estate.