On the comparison of occupancy in relation to energy consumption and indoor environmental quality: a case study

The present work focusses on the investigation of the correlation between occupancy, energy performance of the building as well as the quality of the indoor environment in terms of the thermal and air quality aspects. In this respect 3 different types of rooms (use and occupancy), situated in a building of the National University of Singapore campus, were selected. The building is equipped with an advanced BMS system capable of assessing the energy performance, the thermal behaviour and the air quality of all sections, thus providing guidelines towards a zero energy performance maintaining an acceptable indoor environment. The results indicate that strong correlation between energy consumption and occupancy is identified while the levels of illuminance do not seem to be strongly influenced by the amount of people. The indoor concentration of CO2 which is related to human exhalation, found to be high especially during the class hours. This is attributed to the insufficient performance of the mechanical ventilation central system which cannot be adjusted accordingly.