Prediction of Indoor Visual Environment and Lighting Energy of an Anidolic Light-duct System in Classrooms

Classrooms are mostly occupied during the daytimes. However, most of the domestic school classrooms depends upon electric lighting due to the lack of proper daylighting design. Our recent survey on school classrooms revealed that most of the classrooms used textile curtains or manually operated blinds to block strong sunlight near the windows, then those shading devices significantly reduced entire illuminance levels across the classrooms. Daylighting in classroom have many benefits for teachers and students. Non-image optics, well known for its application to solar concentrators, was used to set up novel daylighting systems that aim at an efficient collection and redistribution of the diffuse component of daylight. These innovative devices are called anidolic systems. The purpose of this study was to analyze indoor visual environment in terms of DA, and lighting energy of classroom installed anidolic horizontal light-duct system by using dynamic lighting simulation program(DAYSIM). The simulation result showed that the system improved DA of deep zone reducing about 30% of lighting energy in classroom