Geothermal energy from abandoned coal mines

Mine water energy

One quarter of residential properties in the UK sit on the coalfields.

When underground mines are abandoned, the pumps that kept them dry are often switched off and the mines fill with water. This water is heated by geological processes, and remains stable year-round.

The Coal Authority have calculated that the constantly replenishing water within these mines could provide all of the heating requirements for the coalfields population. It could also be used as heat and energy for horticulture, manufacturing, and other purposes.

The abandoned coal mines in the UK present an enormous opportunity to the UK as a source of geothermal energy.

Jeremy Crooks – Head of innovation at the Coal Authority

The water in these mines is a low carbon, sustainable heat source, which under the right conditions can also compete with public supply gas prices.

In the case of a district heating network, this energy can be transferred to a pipe network using a heat exchanger, and then distributed to nearby homes.

Seaham Garden Village

In partnership with Durham County Council and the Coal Authority, Tolent Construction are developing an exemplary Garden Village at Seaham, County Durham.

This development has the potential to make Seaham Garden Village the first large scale mine energy district heating scheme in the UK.

The proposed Seaham Garden Village development
The proposed Seaham Garden Village development

The Seaham Garden Village development will consist of 750 affordable homes, 750 private homes, a school, shops, and medical and innovation centres.

It is to be built immediately adjacent to the Coal Authority’s Dawdon mine water treatment scheme. This scheme protects vital drinking water abstraction from Durham Magnesian Limestone, and pumps 100 to 150 litres of mine water per second to the surface for treatment.

Remediation of mine water at Dawdon mine water treatment scheme

This mine water is warmed by geothermal processes to provide a continuous supply of water at 18 to 20°C.

With mine water temperatures unaffected by seasonal variations, there is a potential 6MW of low cost, low carbon sustainable energy available for local space heating use from the Dawdon treatment scheme all through the year.

The scheme is also unusual in that it does not use metal pipes, due to the lower temperatures involved.

Heat from abandoned coal mines is an innovative and practical solution to one of the big challenges facing the economy – decarbonising heat supplies. There would be wider benefits to this sustainable energy source too, as it would also attract new investment, create employment and deliver lower fuel bills to Seaham Garden Village and to other district heating schemes to be built on the coalfields.

Jeremy Crooks – Head of innovation at the Coal Authority

The method of delivery is much cheaper than district heating schemes using higher temperatures, where metal piping is essential and has greater temperature losses, making networks such as Seaham Garden Village much more viable than most district heating schemes.

Our specialist mine energy team can provide advice, support and consultancy to a range of external stakeholders about projects across the UK.