Photo from Spanish geothermal heat from old mines: Hunosa
About one-quarter of British homes sit on a coalfield. An estimated 2 billion cubic metres (2 trillion litres/4.4 billion gallons) of warm water occupy the old mine shafts. At the surface, the water’s warmth can be used to heat buildings above ground with a little supplemental warmth from an electrical heat pump. Once its heat has been absorbed, the water is then returned to the mine workings to be warmed up again. The water is hot enough to heat homes in winter, and cool enough to keep them mild when temperatures rise, with just 25% of the carbon emissions of gas. Heerlen in the Netherlands has connected 500 houses and commercial facilities of building space to the town’s district heating network this way. Locations in Nova Scotia and Spain have come up with similar projects. Hopefully we’ll be next.
www.bbc.com/future/article/20210706-how-flooded-coal-mines-could-heat-homes