Energy audits in university buildings in a tropical climate: assessments of air conditioning consumption

We evaluated aspects of energy consumption by air conditioning units in the Polytechnic School (PS) and the Faculty of Architecture (FA) of the Federal University of Bahia (UFBA), Brazil. The methodology involved a Level I energy audit based on energy consumption data in those two departments, information concerning the efficiencies of air conditioning units in operation between 2013 and 2018, and interviews with management agents and users. We encountered mid-level indicators of energy use, corresponding to 58 kWh/m²/year in the PS and 40 kWh/m²/year in the FA. Energy consumption for airconditioning represented 36% of the total electrical energy consumed by the PS, and 19% of the total consumed by the FA. This research is innovative as it contributes to determining air conditioning energy use indices that can serve as benchmarks for other universities in tropical climates. The study also demonstrated the importance of incentivizing the use of natural ventilation to reduce energy consumption while providing comfort-level thermal exchanges. The results of this investigation can be used to elaborate management plans for rational electrical energy consumption in different university departments.