Britain is sitting on a source of cheap energy. No, not coal – though this cheap energy comes from an unexpected consequence of our industrial past.
The coal industry left behind 23,000 or so abandoned mines. Over the decades, many of these mines have naturally flooded with water, which is heated by the ground to between 12°C and 20°C. This geothermal heat can be extracted, boosted, and used to heat homes. And it’s starting to happen. It has been successfully trialled at 350 homes in Gateshead and will be expanded to around 1,500 homes in the next few years.
The system effectively replaces standard household boilers with a giant, communal heat pump by transferring the heat to a “clean loop” of hot water that flows through a home’s pipes and radiators – meaning no dirty mine water enters the home.
And because most of the warmth in the heat pump is transferred rather than generated, they are typically three to five times more efficient than conventional heating technologies like gas boilers, which heat the water from scratch.
As a result, those homes using heat generated in the Gateshead mine project are being given a 5 per cent discount on their heating bills compared with if the heat had been generated by a gas boiler.
