Geothermal energy to be drawn from coal mines – the multi-million pound renewable energy idea
In a post-coal world, abandoned coal mines exist all over Britain. These mines are flooded with temperate waters around 20oC, presenting a valuable reservoir of 63MW of potential heat. These mines are already being pumped to avoid disastrous flooding, so the idea to then exploit this extracted water’s heat has become seemingly intuitive.
This type of heat extraction and elevation for commercial use is the very task heat pumps were designed to perform.
Much like when we extract heat from the ground using a heat pump, there are a few parallel concerns to consider in this case:
Potential depletion of the minewater resource (analogous of depleting heat store in the ground).
Achievable flowrates, an important factor in any vertical borehole deisgn.
Potential toxins abraded from the mine walls which may be corrosive or harmful to the heat pump equipment.
The South Tyneside council are deploying a £7m scheme, one of the first of its kind in England, which will draw this trapped geothermal energy from the mines in the former Heburn Colliery in order to heat council-owned buildings in the town.
This project aims to extract the water via boreholes, drilled 300-400m vertically into the Earth. Using heat pump technology, this water will be compressed, elevating its temperature further, ready to be distributed to a heat network.
”This is a highly innovative scheme which will be on the first council minewater district heating systems in the UK” – Cllr Joan Atkinson.
This scheme is a cornerstone in the council’s efforts to become carbon neutral by 2030, touting them as being truly committed to becoming a greener borough. It will help them well on their way, as it is estimated that the project will result in a whopping 319 tonnes reduction in carbon emissions a year.
More information on minewater projects can be found at the following links including articles referenced in this post: