Effective Use of Daylight in Office Rooms

The rational use of daylight can significantly reduce the cost of electricity for artificial lighting. This research aims at investigating the parameters of translucent structures of building envelope, and the value of daylight factor, for which maximum efficiency of daylight usage is achieved in office rooms. The study analyzes the dependence duration of daylight autonomy in office rooms, on the value of daylight factor for four European cities. The specific daylight autonomy (h/(year∙m2)) of office rooms were found. It was proved, that regardless the size of the rooms, the maximum specific daylight autonomy in Ternopil city (at illumination of 300 lx, which is prescribed by regulations), with lateral daylight, occurs when the daylight factor is in the range of 1.7% to 1.9%. Maxima – at 1.8%. At illumination of 500 lx, the maximum specific daylight autonomy will occur at a daylight factor range of 2.6% to 3.0%. Maxima – at 2.8%.