The Effect of Shading Position on The Thermal Comfort Commercial Buildings Through Energy Retrofitting

The Surabaya building sector is a prime target for energy efficiency initiatives, given its substantial contribution to overall energy consumption. Commercial buildings, often filled with glass to harness natural lighting, inadvertently raise room temperatures and increase cooling demands. Thus, ensuring thermal comfort within these structures becomes paramount. An energy use survey reveals that air conditioning accounts for a significant 62% of consumption, underscoring the need for retrofitting, especially in commercial buildings. This study centers on retrofitting strategies, focusing on the application of shading devices to glass exteriors, aimed at reducing solar heat gain and, consequently, heat transfer through the building envelope. The research investigates two shading positions: horizontal and vertical, each with specific opening angles and width variations. The Computational Fluid Dynamics method, assisted by CFD software, serves as the simulation tool, exploring shading opening angles at 0°, 30°, and 45°, and shading widths at 20% and 60% of the window glass height. Simulation results highlight the efficacy of horizontal shading, boasting a 60% width of the glass height and a 45° opening angle, which reduces temperatures by a significant 2.5278°C. Additionally, a cost-benefit analysis reveals substantial electricity consumption savings post-retrofitting, amounting to 7619.9 kWh. This translates to best-case cost savings of Rp15,586,068 and worst-case savings of Rp10,390,712, with respective payback periods of 1.57 and 2.52 years.