Effect of External Shading and Window Glazing on Energy Consumption of Buildings in Bangladesh

Abstract

Energy efficiency of buildings is attracting significant attention from the research community as the world is moving towards sustainable buildings design. Energy efficient approaches are measures or ways to improve the energy performance and energy efficiency of buildings. This study investigated various energy-efficient approaches for residential building. External shading controls the solar energy on a window and the energy transfer within the room through the window. In the present study, the effect of overhang and fin on single clear glazing window as well as the effect of advanced glazing on the solar energy transmitted into or lost from the room through the fenestration areas have been evaluated for typical residential buildings in Bangladesh, using EnergyPlus software in different frontage wall orientation. Four types of glazing (single clear, double low-E opaque, double layer argon gapping, and double clear glazing) and six types of window shading ( with different dimensions of overhang and fin) are used in this project. It was found that appropriate overhangs or side fins in the north, south, west and east windows would lead to the optimal reduction of the annual energy transferred into the buildings and can have an energetic behavior equivalent to high performance glazing. As 'V well as the energy consumption for north facing window with overhang and side fin in left side is the lowest and generously shaded (like north facing) south-facing window can also be used for residential building with considering cp index i.e., ener 11 gy consumption can be reduced by proper window shading. In addition, double low-E opaque glazing in window is more efficient for energy saving in building. But with considering illuminance and energy consumption Double low-E clear (Argon) is best selection for Bangladeshi climate.