Journal of Korean Institute of Architectural Sustainable Environment and Building Systems ISSN:1976-6483(Print) 2586-0666(Online) 한국건축친환경설비학회논문집

Thermally activated building system (TABS) has been regarded as one promising technology for energy saving and green-house gas reduction due to the efficiency improvement of a cooling/heating equipment, and feasibility of combining other promising technologies such as ground source heat pumps or cooling towers. TABS can be achieved by running hot/cold water through pipes embedded in a building’s construction. Compared to conventional HVAC systems, TABS delivers higher water temperatures for cooling, and lower water temperatures for heating due to large heat exchange areas. Furthermore, water systems have less transport energy and ductwork spaces compared to existing air systems, due to high thermal capacitance of water. Because of the surface condensation problems in hot and humid weather conditions, TABS needs to be integrated with dehumidification system such as variable air volume (VAV) system or dedicated outdoor air system (DOAS). This study aims to evaluate the cooling energy consumption characteristics of thermally activated building system (TABS) integrated with DOAS in office building compared to the TABS with VAV system. In this study, the design cooling load in office building was firstly evaluated and indoor thermal environment was discussed by considering the surface condensation risk. Finally the cooling energy consumption of TABS with DOAS was compared with TABS and VAV system operation. When the total cooling energy consumption during the cooling period is compared, it is found that the integrated operation of TABS with DOAS is 24% more energy-efficient than integrated operation of TABS with VAV. Night-time electric energy consumption accounts for 34% of the total cooling energy consumption.