Edinburgh Napier University

  This paper explores the possibility of utilising geothermal energy in an existing district heat network in the Aberdeenshire village of Ban-chory to provide hot water by the creation of a hypothetical geothermal well. It considers a simulated deep geothermal single well with a depth of 5000 m. The well operates by injecting a fluid, chosen as water, into the annulus of the well then pumping it back up the central pipe of the well. As the fluid travels down the annulus heat transfer takes place between the annulus fluid and rock formation. As the fluid is pumped up to the surface heat transfer also occurs between the extraction well and the surrounding annulus, further contributing to the overall thermal transfer model. The hypothetical well was created using the dimensions of existing oil wells which once have reached the end of their lifecycle hold the potential to be repurposed for geothermal use. It was found that the thermal output of the well decreases over time due to the drop in local rock temperature which is a result of thermal extraction. Given this the thermal output after a year of operation was calculated and found that to directly supply the Banchory heat network a volumetric flow rate 4.8m 3 /hr was required. After a year of operation, the sites peak thermal production was 108.4kW which equates to a production of more than 949.9MWh over the first operational year.