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Underground mines in Arctic and Subarctic regions require the preheating of mine intake air during win-ter. The cold fresh air of those remote areas can be as severe as-40 °C and commonly needs to be heated to around+3 °C. This extensive amount of heating is usually provided by employing large-size air heaters, fueled by diesel, propane, natural gas, or heavy oil, leading to high energy costs and large carbon foot-prints. At the same time, the thermal energy content of a diesel generator sets (gen-sets) exhaust is known to be one-third of the total heating value of its combusted fuel. Exhaust heat recovery from diesel gen-sets is a growing technology that seeks to mitigate the energy costs by capturing and redirecting this commonly rejected exhaust heat to other applications such as space heating or pre-heating of the mine intake air. The present study investigated the possibility of employing a simple system based on off-the-shelf heat exchanger technology, which can recover the waste heat from the exhaust of the power gen-eration units (diesel gen-sets) in an off-grid, cold, remote mine in Canada for heating of the mine intake air. Data from a real mine was used for the analysis along with environmental data of three different location-scenarios with distinct climates. After developing a thermodynamic model, the heat savings were calculated, and an economic feasibility evaluation was performed. The proposed system was found highly viable with annual savings of up to C$6.7 million and capable enough to provide an average of around 75% of the heating demand for mine intake air, leading to a payback period of about eleven months or less for all scenarios. Deployment of seasonal thermal energy storage has also been recom-mended to mitigate the mismatch between supply and demand, mainly in summertime, possibly allow-ing the system to eliminate fuel costs for intake air heating.