Quantification of thermal adaptation in air-conditioned buildings of composite climate, India

Abstract India has diverse climatic conditions and thermal adaptation can play an important role in defining thermal comfort conditions in air-conditioned spaces. Taking present study as scope, a field study was conducted in nineteen air-conditioned buildings of the composite climatic region of India. The objective was to evaluate thermal environmental conditions in air-conditioned spaces and to quantify adaptation based on air temperature and Standard Effective Temperature (SET*) approaches of thermal comfort. The study ascertains thermal neutrality, comfort bandwidth and thermal acceptability with respect to air temperature and SET* approaches. The research methodology was through a questionnaire administered to building occupants for recording thermal, relative humidity and air speed sensations. Simultaneously, thermal environment variables were also recorded considering Class-II protocol of field measurements. During the study, total 1020 responses were collected. The neutral temperature of the group was found to be 27.5 °C and 26.36 °C based on air temperature and SET* approaches, respectively. Furthermore, thermal acceptability for both 80% and 90% limits were determined for both the approaches as per the method proposed by referred field studies of thermal comfort. The subjects showed a significant adaptation to outdoor temperatures and observed variation in comfort temperature with SET* approach was found to be nearly different. In addition to variation in comfort conditions, the result shows a higher thermal acceptability in conditioned environment.