Optimizing Early-Stage Design for Energy-Efficient Schools in Bandiagara, Mali

In Bandiagara, Mali, extreme heat, humidity, lack of modern amenities, and low literacy rates present significant challenges in building design. Designing a school aims to provide access to quality education, foster community development, and promote sustainable building practices to empower the local community through job creation and the use of local resources. To address these concerns, this study focuses on an early-stage school model to determine the optimal window-to-wall ratio (WWR), rotation, and aspect ratio of the building. The analysis process includes three steps: (1) determining the input values based on ASHRAE 90.1 2019; (2) analyzing models with various aspect ratios (1:1, 1.3:1, 1.5:1, 2:1, 2.7:1, 3.2:1, 4.2:1) to find the optimum energy use along with five different WWRs (0.1, 0.3, 0.5, 0.7, 0.9); (3) rotating a selected model to find the optimal orientation for the lowest energy consumption (30, 60, 90, 120, 150 and 180). The optimal aspect ratio, WWR, and rotation were chosen based on the optimum total energy consumption (cooling, heating, equipment and lighting) over a year. Energy analysis was executed through Climate Studio 2.0 in Rhino 8.14, following ASHRAE 90.1 2019 standards. The findings indicate that aspect ratios of1.3:1 and 1.5:1with WWRs 0.1 and 0.3 with no rotation (0-180o: west-east stretched) have the optimum total energy consumption [kWh/m2] for an educational building in this climate and Bandiagara. These choices could be a framework for designing energy-efficient educational buildings in the early stage without relying on extensive mechanical systems in this region or any other region in similar climates.