A £6.5 million EU grant has been awarded to pump naturally-heated water from an old coal mine in Caerau, Wales to heat 150 local homes.

The Welsh government said the multi-million initiative will “catapult” the area to the “cutting edge” of the UK’s “green energy revolution”.

Cabinet secretary for energy, planning and rural affairs, Lesley Griffiths, today (19 January) announced the £9.4 million project has been awarded £6.5 million in EU funds.

Underground mine water from the workings of the former Caerau colliery, which closed in the late 1970s, would be used to heat houses, a school and a church in Caerau in the Llynfi Valley, South Wales.

Bridgend County Borough Council is investigating how the water, which has been heated by the earth and is a geothermal source of energy, could be extracted, using heat pump technology and a network of pipes, to warm around 150 nearby homes.

The Welsh government said the scale of the scheme will be the “first of its kind in the UK” and would use existing radiators to heat homes without mine-water ever entering residents’ properties.

Griffiths, said: “Our ambition is for our nation to be a world leader in pioneering low carbon energy. This is a cutting-edge model of generating a clean source of renewable energy, drawing on the legacy of our coal mining heritage. It will not only attract further investment to the area, but also address fuel poverty by cutting energy bills and has the potential to be rolled out to Wales and beyond.

“This EU-funded scheme will also create jobs both within the initial construction period and the ongoing supply chain, as well as offering training and educational opportunities in a very innovative area.”

Test drilling carried out at the Old Brewers site in Caerau found the mining void is full of water to a depth of 230 metres.

The results of a feasibility study to determine if the water is warm enough to heat homes is expected by the end of February.

The British Geological Survey has been involved in testing the temperature, chemistry and volume of the mining water, with the temperature expected to be around 20.6 C – warm enough for the scheme to be a success.

Councillor Richard Young, Bridgend County Borough Council’s cabinet member for communities, said it was the volume and temperature of the water at the site that made the scheme possible.

He said: “The next phase is to work through the full scope of the scheme and put everything in place to deliver a trailblazing project for the Llynfi Valley. It will also act as a catalyst for other energy project investments, possibly through the City Deal and other investment.”

While the initial heat network will involve 150 properties there may be potential for the scheme to eventually warm up to a thousand local homes, the Welsh government said.

The scheme is a demonstrator project for the UK Government led Smart System and Heat Programme. The remaining funds for the £9.4 million scheme will be made up by the UK government, Energy Systems Catapult and Bridgend County Borough Council. Other partners include: BGS, Kensa, Egnida, SPECIFIC, Carreg Las, Natural Resources Wales and The Coal Authority.

Findings from the feasibility study will be shared with Caerau residents in an exhibition planned for spring, while construction is expected to start in 2020.

Holland opened the world’s first mine-water power station in 2008 in the town of Heerlen – a Dutch coal-mining area that closed its last mine in the 1970s.

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