A COMPARISON OF THE ENERGY PERFORMANCE OF A CONVENTIONAL VARIABLE AIR VOLUME SYSTEM WITH A TWO PIPE FAN COIL UNIT SYSTEM FOR AN INSTITUTIONAL BUILDING

Abstract

The problem of climate change is nothing new in the 21st century. Air-conditioning system generates 40-50% of the buildings’ electricity consumption. In accordance to 2007 United Nations Environment Programme (UNEP) report, building sector alone is responsible for 30-40% of worldwide energy consumption and nearly 40% of all greenhouse gas (GHG) emissions. Among the different buildings in Singapore, commercial and institutional building accounted for 16% of the total CO2 emission. Therefore, institutional building is selected due to its high dependant on air-conditioning system. The objective of this study is to reduce the cooling and fan power energy of the selected institutional building. Data collection was carried out for the generation of base cases by using Visual Doe software. In order to meet the objective of the study, several energy conservation measures (ECMs) are implemented in order to cut down cooling and fan power energy of the building. Analyses were conducted for verification of the effectiveness of the recommended ECMs. The research design consists of four stages. They are data collection, verification of the data, generation of base cases using Visual Doe software and recommendation of ECMs. Interview with technical support officer is significant for data collection process. In addition, walkthrough of building is also constructive in determining the occupancy pattern of the building. From the results of the simulation, Two Pipe Fan Coil Unit System (TPFCUS) is shown to be more energy efficient than Variable Air Volume System (VAVS) for the selected building. From the comparison of energy savings achieved for cooling and fan power energy between TPFCUS and VAVS during term time and semester break, TPFCUS appears to cut down as much as 57.4% of cooling energy during semester break as compared to VAVS. Furthermore, there is some limitation of the software which could affect the accuracy of the base cases generated. Simulated results would be improved if more operational information were available.