Passive cooling in tropical residential buildings using thermal and energy performance analysis

Abstract The sharp rise in global energy consumption has led to a sharp increase in carbon emissions, primarily due to the continued dependence on fossil fuels as the main energy source. Building operations are a major contributor, accounting for approximately 34% of total energy use, with air conditioning systems alone responsible for 7% of global electricity use. In response to the escalating threat of global warming, many countries have committed to adopting net-zero carbon strategies by 2050. Solar shading devices, as critical elements of building facade design, offer significant potential for cooling load reduction by controlling heat gain from the sun through windows and other glazed surfaces. While various shading geometries have been implemented in buildings worldwide, their effectiveness varies based on window orientation and local solar angles in different climatic conditions. Although numerous studies have investigated shading devices in tropical climates, there is limited research focusing specifically on optimizing shading geometry for residential buildings in the Philippines. The research aims to address this gap by evaluating the performance of different shading geometries applied to a typical two-storey residential building in Manila, Philippines. The Integrated Environmental Solutions Virtual Environment software was utilized for a series of numerical simulations to assess how variations in solar shading devices impact solar heat gain and indoor thermal comfort. Results indicate that incorporating shading mechanisms, such as horizontal overhangs and blinds, reduced cooling loads by up to 5% annually, with monthly reductions up to 29 kWh. Additionally, indoor operative temperatures decreased across different scenarios, maintaining a comfortable range of 25−27.2°C. The investigation’s findings shall augment the expanding body of knowledge on effective solar shading geometry and inform future facade design practices in the Philippine context.