Effect of Building Fabric on the Electricity Demand for Space Cooling for Attaining Thermal Comfort in a South Indian Community Building

The world’s second-largest populous country, India, is likely to experience space cooling-related electricity consumption quadrupling in the next two decades, especially in residential buildings, with only 8% Indian households having air conditioning (A/C) in 2017. With the rapid change in the climate in recent years, resulting in higher environmental and heat stress in India, the ownership of A/C is rising rapidly. However, the conventional building fabrics in India – in general, dominated by burnt brick – has a generally unsatisfactory performance as an insulating material, which is needed when the A/Cs are operational. Therefore, studying the effect of different building fabrics on cooling is essential for reducing and managing the projected electricity demand. The construction strategies might influence climate-specific cooling policies at the state and country levels, encouraging adoption of new low-energy and low-cost cooling technologies at mass-market scale. For high cooling demand projections in India, the objective of this study was to investigate the effect of different building fabric constructions on A/C use, and model resultant aggregated electricity consumption for space cooling reduction strategies in a residential community (Auroville) in southern India. A building thermal model was developed for the community as part of the study, and three scenarios were simulated with different building fabric constructions suitable for Indian context to evaluate the effect on the indoor temperature and use of A/C for attaining thermal comfort. Our results showed the potential of ~1.5% reduction in average daily indoor temperature and ~15% reduction in average cooling electricity consumption during summer by retrofitting exterior walls and roof with insulating materials.