The Influence of Design Parameters on the Operational Energy Carbon Emissions of a Commercial Building in Pakistan

Buildings are responsible for 37% of CO2 emissions and 36% of energy use worldwide, making them significant contributors to both energy use and carbon emissions, due to which building energy efficiency is currently a top priority for regional, national, and global energy policy. This study evaluates building design features, such as window wall ratio (WWR), orientation, and shading coefficient (SC) for its single-, low-E double-, and low-E triple-glazed windows. The building analyzed in this study is a hypothetical commercial building located in Lahore, Pakistan (ASHRAE zone 1B). The results show that compared to unglazed windows with a SC of 0.2 and 0.3, peak cooling total load (PCTL) and CO2 emissions are reduced by 17.84% and 17%, respectively, for single-glazed windows. Similarly, low-E double-glazed windows reduce 21.3% and 20.9% in PCTL and CO2 emissions, while low-E triple-glazed windows result in reductions of 21.8% and 21.1%, respectively. Reducing the WWR from 15.14% to 4.94% results in a 5.35% reduction in PCTL and CO2 emissions. Moreover, Using the optimized orientation of the building (180° clockwise from north) further decreases PCTL and CO2 emissions by 8.63%. This analysis concludes that significant energy and environmental gains can be achieved by higher-quality windows, utilizing optimized orientation, and reducing the WWR. In addition to ensuring long-term cost savings, this strategic approach promotes a more sustainable and environmentally friendly future for future generations.