Comparative Energy Analysis of a Constant Air Volume (CAV) System and a Variable Air Volume (VAV) System for a Software Laboratory

The objective of heating, ventilating and air conditioning (HVAC) systems is to satisfy users when it comes to health, indoor air quality (IAQ), and thermal comfort. Air conditioning systems employed to provide thermal comfort and indoor air quality consume a significant part of building energy requirements. Any effort to minimise energy consumption improves cost effectiveness and economics. A variable air volume (VAV) system is a choice in that direction. In this research, a relative energy consumption analysis of a constant air volume (CAV) system and VAV system has been performed. For the purpose of this study, a software laboratory was taken and the load pattern was determined. For the derived load pattern an energy analysis of major components of the HVAC system was carried out. It was found that energy savings in the chiller varied from 14 % to 20 % and that fan energy savings were between 20 % and 48 %. To meet indoor air quality (IAQ) requirements a ventilation strategy based on air quality demand control ventilation (DCV) was evaluated. This took into account the contaminants generated from both human and other sources such as the building and equipment, etc.