Thermal comfort and energy consumption in cold environment with retrofitted Huotong (warm-barrel)

This study aims to investigate subjective comfort and energy consumption in cold environment with retrofitted Huotong (warm-barrel). A series of experiments was conducted in one experimental room in Hunan University, China in winter. 16 subjects were exposed to the environments at 9, 12, 15 and 18 °C with retrofitted Huotong. During each test, subjective responses and Huotong's energy consumption were recorded. The obtained results indicates that Huotong maintained overall and local comfort in cold environment. With it, 90% acceptable temperature range could be extended to 9 °C. Thermal sensation, comfort and acceptability improved within 15 min after subjects turning on Huotong, while their preference for warm environment was weaken. Moreover, the heating power required for maintaining comfort increased as temperature was lower. When air temperature dropped from 18 to 9 °C, the average heating power rose from 50.3 to 165.6 W for each person. In addition, based on Corrective Power (CP), a new index (Corrective Energy & Power, i.e. CEP) for evaluating performance of both comfort and energy consumption of personal comfort system (PCS) was proposed. This index makes it possible to compare different PCSs in terms of extending acceptable temperature range and energy-efficiency simultaneously.