Multi-objective optimization to balance thermal comfort and energy use in a mining camp located in the Andes Mountains at high altitude

Abstract

The mining industry is the largest electricity consumer in Chile. Sustainability reports of Chilean miningcompanies show that electricity consumption of mining camps is 350e500 kWh/m2per year. Despitecold climate conditions, mining camps show overheating, and 40% of the minersfind them uncom-fortable. Mining camps’energy access is difficult because they are located in remote zones. This paperaims to optimize the building envelope and HVAC system to minimize the total energy consumption andeliminate the overheating risk of a real mining camp located at 4400 m.a.s.l. The mining camp is30,000 m2, built of timber prefabricated lightweight modules and hosts 1700 workers. The electricityconsumption of the baseline case is 330 kWh/m2year and shows overheating. Multi-objective optimi-zation is implemented to minimizing the electricity consumption while avoiding overheating. A hybridmultidimensional optimization algorithm implemented in GenOpt, a building energy simulation pro-gram (EnergyPlus) and several scripts developed in Pyhthon for optimizing discrete variables andcalculating the overheating risk of each thermal zone are coupled. Two different cases are optimizeddepending on the heating systems: electric heaters (Case I), which is the current situation; and heatpumps with chilled beams with free cooling option (Case II). This paper shows that an efficient HVACsystem (Case II) is crucial for achieving thermal comfort and minimizing electricity consumption, whichreaches 112.9 kWh/m2year, representing a significant reduction of 66% compared to the baseline case.The optimization process provides not only the optimum set of energy-efficient strategies but also a setof feasible solutions close to the optimum that allowsflexibility to choose other strategies based oneconomic, transportation and on-site construction constraints.