EFFICIENCY OF LIGHT SHELVES ACCORDING TO LATITUDES IN OFFICE BUILDINGS

Abstract

Light shelves are one of the improved daylight systems, help to contribute energy saving by using daylight effective. Many regional studies have been done about light shelf efficiency especially in recent years. This original paper investigates the effect of different latitudes (0°, 15°, 30°, 45°, 60°, 75°) to the light shelf efficiency on a sample unit for 3 different (3m, 3,9m, 4,8m) office heights. First, suitable light shelf conditions are determined for each condition by using Ecotect & Radiance softwares in CIE Standard Overcast Sky and then desired daylight intervals for offices are compared without and with light shelf. Consequently, it is determined that light shelves increase the desired daylight levels in all conditions for 3 different office heights and light shelf efficiency generally; diminishes with increasing of office heights between 0°-15° latitudes and increases with increasing of office heights between 30°-75° latitudes within. In addition to that the distribution of daylight levels are analysed in plans and results are presented to designers interested in daylight efficient design.

Keywords

• Daylight simulation,light shelf efficiency according to latitudes/office height,daylight in office buildings,design sky illuminance,natural lighting.

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