On the potential of building adaptation measures to counterbalance the impact of climatic change in the tropics

Abstract

Climate change is one of the most significant environmental issues facing communities, while poor construction and absence of effective air-conditioning (AC) predominantly cause indoor overheating. Although AC may help meeting indoor comfort, it increases the vulnerability of low-income residents, triggers large energy consumption, and generates anthropogenic heat, which worsens heat stress outdoor. The capacity of buildings to maintain comfortable thermal conditions without mechanical cooling is the key factor protecting occupants against the rising temperature. Residents of Darwin, Australia, will be largely affected by increasing temperature where the annual peak ambient temperature may increase by 7.4 °C in 2060, while the number of hours above 30 °C will rise by 70%. Based on regional climate modelling for the Australian area and using a building energy simulation platform, we computed that by 2060 the indoor air temperature in a typical residential building may exceed 30 °C for over 4000 h under free-floating condition, with a peak daytime and night-time temperatures of 39 °C and 36.5 °C, respectively. The sensible thermal energy need for cooling per unit area under thermostatically controlled condition will increase from the current level of 110.7 kWh/m2 to 196.8 kWh/m2 in 2060. Different adaptation techniques when applied to the typical residential building yield to the peak indoor air temperature drop by 3.3–12 °C, and cooling energy needs reductions by 23.5–195.3 kWh/m2 (12–99.7%) for low, medium, and high retrofit buildings compared to the typical residential building in 2060. Our study indicates that improved building quality is necessary to enhance survivability and energy efficiency in Darwin considering the role of building adaptation measures to counterbalance the impacts of global warming.