James Watt School of Engineering researchers to take part in ground-breaking project to establish geothermal energy as a viable technology for Scotland’s central belt by creating at least three new geoenergy facilities.
The University has recently unveiled its participation in a ground-breaking project to establish geothermal energy as a viable technology for Scotland’s central belt by creating at least three new geoenergy facilities. The HotScot consortium behind the project involves universities, institutional bodies, and partners from the industry.
The proposal is one of 17 shortlisted for financial support from academic funding body UK Research Institute (UKRI), with the final bid to be submitted in late 2020. Between three and five former mines are to be selected for the development of new mine-water ground heat exchange or storage sites following screening by academics from the universities involved, and other partners.
Working closely in partnership with other members of the consortium, (Heriot-Watt University, Stirling University, British Geological Survey, Community Energy Scotland, ENGIE, Envirocentre Ramboll, Scottish Enterprise, SSE Enterprise, Synaptec, Synergie Environ, and TownRock Energy) a University of Glasgow team led by the energy and sustainability research group’s head professor Gioia Falcone will contribute to creating the criteria that will determine feasible sites, aiming to balance optimal resource exploitation with the benefits to the local economy. They claim that investment in mine-water geothermal could deliver economic growth totalling £303m, and 9,800 jobs.
This new project follows research gained from an earlier test site established by the UK Geoenergy Observatory (UKGEOS) in Rutherglen, Glasgow. With 12 boreholes fitted with hydrogeological sensors, it was designed as a model of future mine-water geothermal energy plants allowing researchers to better understand heat flow in underground water channels.
Holyrood has committed to make Scotland a net-zero greenhouse gas emitter by 2045, beginning with the decarbonisation of the region’s power production. The long history of resource extraction has left scars across the central belt (also known as the Midland Valley), from spoil heaps and quarried rock faces to flooded mine-workings that burrow under even the University’s Western Infirmary Campus development; but these also present opportunities to decrease the cost of new green energy systems.
The true number of abandoned mines across Scotland is unknown, as owners were only required to register closed sites from the mid-19th century onwards, leaving earlier ones to be discovered by chance, redevelopment work, or subsidence. Some of these redundant mine-workings draw flows of warm water from Scotland’s hot sedimentary aquifers deep beneath the surface of the central belt and may be cheaper and easier to access (extract low-grade heat from) than traditional geothermal boreholes.
However, the natural flooding of these mines also provides a risk of groundwater contamination.
A 2019 paper (Digging deeper: The influence of historical mining on Glasgow’s subsurface thermal state to inform geothermal research) by NM Burnside, who is also of the University’s energy and sustainability research group conducted research on the topic. SM Watson and R Westaway noted that research in the late 1980s after the oil crisis had identified the hot sedimentary aquifers in the Midland Valley as a potential geothermal energy source, but that the prevailing view of the time was that the cost and risk of exploitation would be too great. They posit that horizontal flow from hot aquifers into mine workings led to lower heat flow readings than obtainable, such that exploitation is more feasible and rewarding than previously thought.
At present, the Scottish government has failed to meet its previous goal of providing 11% of Scottish heating needs through renewable sources by 2020, achieving only 6.3% in 2018. At the rate that the proportion increased from 2017 to 2018, they would have only achieved 7.9% by now.
Announcing the project, the consortium claimed geothermal energy from such abandoned mines could meet 8% of Scotland’s domestic heating demand. This cannot be verified at present.Professor Shipton, who is leading the project, has co-published 36 papers, articles, and project reports to date with University of Glasgow academics, most recently with Dr Alistair McCay, and two other external authors, on the effects of fluid flow within shales (published in The American Association of Petroleum Geologists Bulletin, and funded by Nuclear Decommissioning Authority EPSRC). Dr McCay’s main research interests are in-ground heat exchange using subsurface hydraulic systems.
