Comparative assessment of energy performance, GHG emission, and environmental performance of exterior wall alternatives for the buildings in an educational campus in Kolkata, India

The building sector contributes to 40% of energy consumption and one-third of the greenhouse gas emissions globally. The building’s energy use involves operational energy (OE) for comfort and operations, along with the embodied energy (EE) embedded in the building materials and the energy spent over the building’s lifetime during building construction and maintenance. This paper aims to establish a methodology for estimating both the embodied and operational energy and embodied and operational GHG emissions of an educational institute campus in Kolkata, India while exploring the cumulative energy and environmental performance of various façade construction materials. The study further identifies the best-performing façade construction material in terms of energy and environmental performance. The embodied and operational energy and the environmental performance of the seven masonry units, two types of mortar, and two kinds of plaster options are compared. The operational energy was in the range of 146 to 166 kWh/m2/Year for the base case, which involved the typically practiced solid burnt clay brick walls. The study revealed, that replacing the conventional solid burnt clay bricks along with cement mortar and cement plaster, with cement stabilized soil blocks in combination of cement mortar and gypsum plaster can curtail the overall energy requirement by 19.35% and improve the environmental performance by reducing the cumulative GHG emissions by 8.31%. A complete life cycle analysis covering the entire building lifecycle stages is also carried out and the cement stabilized soil block walls show 5.0% lesser life cycle energy consumption and 6.14% lesser life cycle GHG emission over the baseline.