Multi-Criteria Optimization of Tubular Daylighting Devices for Classrooms in High-Solar Climates through Parametric Simulation

In educational architecture, particularly in high-solar climates, achieving a balance between ample daylight and visual comfort is a significant challenge. This numerical study evaluates the daylighting performance of nine tubular daylight device (TDD) configurations, with diameters of 250 mm, 350 mm, and 540 mm, using one, two, or four units, in a 35 m² classroom located in Batna’s high-sun climate. By combining glare hotspot distribution with a weighted multi-criteria assessment (Daylight Autonomy, Useful Daylight Illuminance, Annual Sunlight Exposure, and uniformity), the research identifies optimal solutions that balance daylight provision and visual comfort. Among them, the 4×350 mm configuration performs best, limiting overlit areas to 20.7% (vs. 37.1% for 4×540 mm) and significantly reducing glare hotspots, while the 2×540 mm and 4×540 mm setups lead to 1.6-fold and 3.6-fold increases in glare zones, respectively, compared to 4×350 mm. This configuration also achieves the highest global score (66.5%) thanks to its low ASE (10%) and high UDI-a (74%). In contrast, the 4×540 mm setup, despite its superior DA (81%), presents unacceptable glare risks (65% ASE) and poor lighting uniformity. The study underscores the importance of prioritizing daylight quality metrics (UDI-a, ASE, glare control) over simply maximizing illuminance in sunny climates. These findings align with EN 17037 and LEED v4 guidelines and offer actionable insights for improving visual comfort in educational spaces.