Journal Papers

Journal: Energy and Built Environment, Volume 4, Issue 6

Authors: Sriraj Gokarakonda, Christoph Van Treeck, Rajan Rawal, Stefan Thomas

Abstract: Studies show that people can tolerate elevated temperatures in the presence of appreciable air movement (e.g., by using ceiling fans). This results space cooling

energy savings by reducing the use of air-conditioners and extending their set point temperature (Tset). However, there is little empirical evidence from India on the energy savings from the use of ceiling fans with air-conditioners. To address this gap, we analysed the energy performance of room air-conditioners (RACs) with both fixed speed compressors and inverter technology at different set point temperatures (Tset) and ceiling fans at different Fan Speed Settings (FSSs) in relation to thermal comfort conditions according to the Indian Model for Adaptive Comfort-Residential (IMAC-R) in 15 residential mixed-mode buildings (MMBs). The study showed that using high FSSs with RACs resulted in unnecessary energy consumption. Compared with the mandatory default Tset of 24°C in the Indian RACs, the results showed that at all FSSs, Tset at 28 and 30°C maintained thermal comfort conditions, i.e., the indoor air temperature (Tin) was between the neutral operative temperature (Tneu) and lower 80% thermal comfort band according to IMAC-R and resulted in mean RAC energy savings 44 and 67%, respectively. Furthermore, at different Tset, RACs with inverter technology consumed 34-68% less energy than fixed speed compressors.

Keywords: Room air-conditioners; Ceiling fans; Set point temperature; Thermal comfort