The paper can be access online for free at https://pangea.stanford.edu/ERE/db/WGC/papers/WGC/2020/08025.pdf.

Keywords: geothermal, heat, energy, Scotland, UK, aquifers, mines, granites, minewater, groundwater, water, thermal, networks, business, commercial, models, case, feasibility, studies, policy, on the rocks, Scotch, whisky.

Abstract:

Despite valiant efforts, there are still no significant geothermal energy projects installed in Scotland, and only a few significant open-loop ground-source heat pump projects. This paper tells the stories, in brief, of these efforts, primarily made by a small company TownRock Energy (TRE). They gathered insight and best practice from projects around the world, from New Zealand to Iceland, California to the Netherlands, Kenya to Hungary. Outlined in this paper are the most important factors to consider when designing an economically viable geothermal heat network in a country with old cold rocks.

In 2015 the Scottish Government launched the Geothermal Energy Challenge Fund, which awarded a total of £234k to five consortia of businesses, local authorities and universities to complete site-specific geothermal heat network feasibility studies. TRE was heavily involved, and whilst none of the original projects were taken forward for test drilling, various consortium members went on to spend the following years hunting for the perfect demonstration sites. TRE has advised clients from all sectors, including airports, universities, and distillers, via over a dozen feasibility studies and business cases, evaluating fractured granites, hot sedimentary aquifers and most commonly flooded coal mines. The findings have been distilled in this paper.

Economic, environmental, social and political parameters all impact the business case. Risk analysis and mitigation is critical. The heat market requires substantial expansion through local and national government spear-heading the development of heat networks. The public sector holds most of the cards to reduce risks and increase incentives to investors in heat networks, or implement direct public sector investment in projects with initial low-returns but long lifetimes.

With the decarbonisation of heat appearing ever higher on the political and social responsibility agenda, the legislative, financial, and social barriers are closer than ever to being broken down. This is a new dawn of low-carbon heat for a country which most importantly needs a sustainable fuel source for the creation of the ‘fire water’ the world adores. Slainte mhath!