Deriving daylight frequency distribution curves from solar radiation data to be used to implement energy saving policies in Palermo, Italy

摘要

The paper presents proposed guidelines for developing a simplified tool to be used for assessing the compliance of proposed projects with city regulations, with reference to the daylighting aspects First, the algorithms proposed for calculating the internal illuminance in a point, based on the assumption of perfectly diffusing glazings, are discussed. The result is a light transmission factor, which is a function of the position of the point and of the geometrical and physical characteristics of the room. Then, the daylight input data to be used for such calculations are presented. In order to provide designers with easy to handle data, this information is presented as frequency curves, showing the illuminance cumulative frequency distribution for a year relative to eight fundamental vertical orientations. There are different curves depending on the building type. These curves are obtained by considering only the data relative to hours and days consistent with the profile of use typical of that type of building.