Dynamic vertical green walls & shading systems integration to enhance energy efficiency & thermal comfort: A case of educational building skin retrofit in a Mediterranean city

Background Since 1900, the Mediterranean coast has experienced a notable increase in average annual temperatures, rising from 20°C to 24°C.This upward trend in outdoor climate plays a significant role in determining indoor environmental quality (IEQ) particularly in educational buildings. With growing concerns about energy consumption and urban climate change, This paper examines the potential of movable green walls on building facades to improve urban ecosystems. Unlike traditional passive green walls, active green walls offer dynamic aesthetics and provide various benefits, including shading, passive cooling, and opportunities for personal expression in urban environments. The primary aim of this research is to evaluate the shading effectiveness and energy performance of DVGS in hot climates, specifically within educational settings, to enhance their design as an architectural feature. ^{1 , 2} Methods A comprehensive approach is employed, specifically designed for the local climate of Egypt, utilizing DVGS to achieve comfort in temperatures and natural sunlight while reducing power consumption to enhance energy efficiency & thermal comfort for the occupants. The novelty of this paper lies in its comparative methodology, enhanced by software simulations (DesignBuilder7.0.2.006-Energy Plus plugin),(hyperlink: https://www.openstudio.net) to address design challenges in the existing educational building. Results The paper highlights the benefits of dynamic vertical green systems (DVGS) in educational institutions, revealing a significant reduction in energy efficiency and air quality. Louvers reduced chilling energy usage by 10.95% and heating energy usage by4.8%, while green walls reduced chilling energy and heating energy usage by 19.14% and 12.94% respectively. Louvers also reduced carbon dioxide emissions by 13%, while green walls reduced emissions by 28.43%. The vegetation layer’s thermal properties improved relative humidity by4% and 8%, respectively, in hot arid environments. DVGS installations also reduced electricity costs by 35% and 41.5% during August peak months. Conclusions The implementation of DVGS significantly improves indoor environmental quality by enhancing energy efficiency, thermal comfort and natural daylight.