Predicted Simulation on the Lighting Energy Saving in a Classroom Using the Sun Shading as the Daylight-introducing Device

Because of the characteristics of the subtropical climate in Taiw an, the abundant daylight can be applied well on the savings of the lighting power. This study was to figure out the illumination environment indoors and to introduce the daylight as far as the inner part of rooms. The field measurement and numerical simulation were adopted. A nine-channel photometer was used to measure the illumination on the table top, and the commercial software which was based on a numerical theory of ray-tracing and radiosity was used. A single-sided day-lighting classroom was taken into account. Close congruence with the experimental results shows the validity of numerical simulations. Results show that the poor uniformity when the daylight is introduced into the interior directly. Simulations show that the improvement in reduction of direct daylight when the shading panel is installed at the proper position, and the benefit on the uniformity and energy saving when the panel can be designed to act as the reflection device.