| Title | Geothermal Energy Use, Country Update for United Kingdom |
|---|---|
| Authors | Corinna Abesser, Andres González Quirós, Robin Curtis, Robert Raine, Hester Claridge |
| Year | 2023 |
| Conference | World Geothermal Congress |
| Keywords | Country update, United Kingdom, low enthalpy, direct use, GSHP, WSHP, mine water, EGS, HDR |
| Abstract | In the reporting period, 2020–2022, there has been a sustained resurgence of interest in all aspects of geothermal energy in the United Kingdom (UK), particularly in the provision of decarbonised heat. Currently, the main area of exploitation are shallow geothermal resources using GSHP (Ground Source Heat Pump) systems, but the exploitation of medium to deep geothermal resources continues to be slow. Utilisation of shallow geothermal via GSHPs has accelerated (from a low base) due to the positive impact of the domestic and non-domestic versions of the Renewable Heat Incentive (RHI) scheme in Great Britain (GB). The domestic scheme closed to new applicants in March 2022 and has been replaced by the Boiler Upgrade Scheme (BUS) which currently favours Air Source Heat Pumps (ASHPs). The nondomestic scheme closed to new applicants in March 2021. Funding schemes for Decarbonisation of Public Sector buildings is also generating interest in various forms of geothermal energy to deliver low carbon heat. The Public Sector Decarbonisation Scheme (PSDS) remains the main funding route to install large GSHP on public buildings. Mine water energy is also of increasing interest and significant private mine water projects have been completed in the Northeast of England and others are in development. The most significant developments in deep geothermal have been the completion of the drilling phases of the United Downs Deep Geothermal Project (UDDGP), and the first well of the Eden Geothermal Project (EGP), both in Cornwall. At United Downs, the production borehole UD-1 was completed to a drilled depth of 5275 m (vertical depth of 5057 m), and injection borehole UD-2 to a drilled depth of 2393 m (2214 m depth). At Eden the first borehole has been completed to 5277 m drilled (4871 m vertical depth)– making it the longest geothermal well drilled in the UK. Both deep geothermal projects have encountered permeable structures at depth in radiogenic granites and have undergone a period of well testing to provide information on temperature and permeability of target zones and to enable characterisation of the geothermal resource to understand how the wells will perform and their expected outputs. The Natural Environment Research Council, through the British Geological Survey (BGS), has established a geothermal research site in Glasgow and is currently in the process of building a second site in Cheshire to investigate aspects of mine water geothermal and of shallow, borehole related geothermal energy delivery, respectively, as part a £31m project funded by the 2014 UK Government Plan for Growth of Science and Innovation. The sites are open to the research community and industry to investigate and innovate multiple aspects of geothermal energy. |