Assessing the performance of façade-integrated transparent photovoltaic panels for daylight and energy generation in high rise buildings of hot & dry climate

Abstract

Indian cities are witnessing a boom in the growth of high-rise buildings to accommodate the ever-intensifying population. The modern trend of applying glass on the façades of tall buildings holds a threat due to Indian climates. Though it allows the daylight, reduces the artificial lighting, and provides a good view, the heat gained through the glass façades increases a building's energy consumption. Therefore, an innovative, advanced strategy is required that replaces the glass with alternatives which can potentially minimize the energy demands either by controlling the heat gain or producing the electricity by itself, to match the demand. Transparent photovoltaic facades can ideally solve this purpose, as it allows the daylight and are multi-functional in nature. It produces electricity and fulfils several other tasks of solar protection and glare protection. But, the presence of solar cells may cause undesirable shading or low illuminance levels; hence, it is important to comprehensively assess the daylight performance and also calculate its energy performance. The aim of the current research paper is to determine the effectiveness of integrating the transparent photovoltaic panels over window/glass façades of daytime-occupied high-rise buildings in a Hot & dry climate and the form configurations required to achieve a considerable amount of energy on-site, without affecting the quantity of daylight. In this study, the performance of the amorphous silicon (a-Si) PV window, with 26.7% visibility, was evaluated through simulation using Rhino+Honeybee software over different building sizes & aspect ratios. The results showed that there was a gradual decline in the energy intensity with increase in length and the energy intensity got increased with an increase in floor height. The form with a high aspect ratio had the highest EPI of 228kwh/m2/year. Further, the form with the least aspect ratio achieved a better daylight performance. The findings of this research are potentially valuable for building designers and decision-makers to foresee the behaviour pattern of BIPV facades in energy generation, while affirming a comfortable and luminous environment.