Basic Study on Performance Evaluation according to Separation Distance of Internal Double Light-Shelf Reflector

Abstract

As lighting energy consumption increases, various studies are carried out to solve such a problem. As a solution to the problem, a variety of studies are conducted since the performance of light-shelf using external natural light is excellent. The light-shelf is divided into external, internal and mixed type light shelves, and also it is divided into single light shelf and double light-shelf according to reflector's installation type. Preceding studies on light shelves are mostly simulation studies. In this regard, this study aimed to conduct an experiment research of double light-shelf, and the study results are as follows: 1) When a double light-shelf is applied, average illuminance increases compared with a single light-shelf. 2) When an internal double light-shelf is applied, uniformity factor declines compared with a single light-shelf, and this is a factor to consider in installing a light-shelf. 3) In case of the internal double light-shelf selected in this study, when separation distance diminishes, uniformity factor improves. Also, when separation distance is 100mm, indoor illuminance distribution is high, which is advantageous to lighting energy reduction. Therefore, proper separation distance of an internal double light- shelf is 100mm on the summer solstice.