Evaluation of data for developing an adaptive model of thermal comfort and preference

Abstract

Energy requirements in India, and in all developing countries, are rising at over 10 per cent annually and may double after 2020. With the Energy Crisis there is a demand for the promotion of greater saving in energy and efficient use of available energy. This not only has the potential to meet the ever-increasing demand but it must be recognized as an important and sustainable solution for the energy crisis as energy saved is energy produced. Many studies have shown that, to the occupants, the most important consideration is thermal comfort. Thermal comfort is defined by ASHRAE, as that state of mind, which expresses satisfaction with the thermal environment. The context of the study of thermal comfort is the multi-billion dollar air-conditioning (AC) industry. The need to define ‘comfortable environments’ arose from this industry. Before air-conditioning buildings were built on the experience of countless builders of the past, experience being passed down the generations. One of the more contentious theoretical issues in the applied research area of thermal comfort has been the dialectic between “adaptive” and “static” models. Apart from having disparate methodological bases (the former laboratory-experimental, the latter field-based), the two approaches have yielded starkly differing prescriptions for how the indoor climate of buildings should be managed. These prescriptions carry implications for the types of permissible building designs, the means by which their thermal environments are controlled, and the amounts of energy they consume in the production of habitable indoor climates. Static models have led to indoor climate standards that have been universally applied across all building types, are characterized by minimal recognition of outdoor climatic context, and are contributing to an increased reliance on mechanical cooling. In contrast, proponents of adaptive models have advocated variable indoor temperature standards that more fully exercise the adaptive capabilities of building occupants. This approach potentially leads to more responsive environmental control algorithms, enhanced levels of occupant comfort, reduced energy consumption, and the encouragement of climatically responsive building design. Despite these apparent differences, our review of the research literature emerging from both approaches indicated that this seemingly irreconcilable split was primarily the result of narrow definitions of the term “thermal adaptation”, and that there were opportunities to bridge some of the gap between the hypotheses. This paper attempts to discuss the methods of evaluating the thermal preferences of the people of composite climate for developing an adaptive model of thermal comfort and preference.