Evaluation of energy and indoor environmental performance of mechanical ventilation systems under different climatic conditions

No clear guidelines are available for operating mechanical ventilation systems with bypass control in order to maintain the indoor environmental quality (IEQ) levels recommended by standards with the minimum possible energy use. This paper used dynamic computer simulations to study the energy and IEQ implications of multiple mechanical ventilation strategies for office buildings under different climatic conditions. Although significant cooling energy savings were achieved by bypassing the heat exchanger during the cooling season, the total primary energy savings only marginally decreased in cold and dry climates. This was due to the fan energy use, which even exceeded the cooling energy savings in hot and humid climates.