ENERGY PERFORMANCE OF ELECTROCHROMIC GLASS UNDER SINGAPORE TROPICAL CLIMATE

Abstract

In Singapore, the building sector takes up almost 38% of the nation’s energy consumptions and the cooling system alone consumes half of the total building energy consumptions. It is thus important to have an advanced window system to reduce the overall cooling demand. This study aims to assess the energy performance of the latest electrochromic glazing under tropical climate and figure out the possible connections between energy savings and other parameters such as ambient temperature, solar irradiance, and relative humidity. In this study, two climate chambers were constructed on the rooftop of a campus building at National University of Singapore, with one chamber installed with the tested EC window (Tv=0.03-0.68) and the other with the reference 6mm clear float glass (Tv=0.89). The results showed that 16% energy saving was achieved when the EC glass was in the bleached state and 24% energy saving in the fully tinted state. Furthermore, radiant globe temperature and west-facing solar irradiance were found to have strong linear correlations with energy savings. However, more parameters can be measured to monitor the indoor and outdoor environment of two chambers, and a control algorism should be developed and optimised to improve the daylighting performance and address problems in thermal comfort in future.