Investigating the potential of mine-based geothermal energy systems

Geothermal energy, the thermal energy harnessed from Earth's crust, is a renewable, low-carbon resource. Underground mines offer a cost-effective means for geothermal utilisation due to elevated geothermal gradients and accessible void spaces. Mine-based geothermal systems can leverage mine ventilation exhaust, mine water, and rock strata; however, mine water based geothermal recovery systems stand out as the dominant mode, particularly in abandoned and flooded mines, where heat pumps can be further utilised to extract thermal energy efficiently. This paper delves into diverse aspects of mine water-based geothermal systems, including different configurations, critical parameters, and critical factors of implementing the technology, including water quality assessments and heat conduction challenges in mine water. The paper presents the results of preliminary modelling of fluid flow and heat transfer in flooded mines, analysing the main parameters influencing the flow and heat exchange processes. By addressing these aspects, the paper aims to contribute to successfully implementing mine water based geothermal systems, thereby advancing sustainable energy solutions in the mining industry.