The thermal power budget approach to estimate the geothermal potential of closed mines

Over the past 5 years, research at the Institut National de la Recherche Scientifique (INRS) in Québec City has focused on the concept of thermal power budget to evaluate the geothermal potential of abandoned and flooded mines. The objective of this paper is to describe this new resource assessment concept and show how it was applied to a variety of mine sites, both open pit and underground, at the early stage of geothermal development. This considers not only the volume of water in the mine, as well as initial and final temperatures, but also the volume of rock involved in heat exchange and water inputs, such as precipitation and groundwater. The gigantic open-pit mines in the Thetford Mines area contain geothermal resources with promising potential for cooling data centres. Studies have also been carried out in Yellowknife (Northwest Territories) to assess the amount of thermal energy that could be produced from a world-scale underground mine integrating geothermal heat pumps.