Evaluation of Angular Distribution Models to Estimate Sky Diffuse Irradiance on Tilted Planes in Urban Environments

Abstract

The great growth of cities in the last century, together with the scarcity of developable land, has led to the growth of high-rise cities, limiting the access to solar radiation for their inhabitants. For this reason, it is crucial to have models that allow an accurate assessment of the amount of solar radiation that can be received in highly obstructed environments. In this work, it has been evaluated and compared the performance of an angular distribution model against a simpler irradiance model to estimate the diffuse irradiance received on tilted planes located in obstructed environments. To this end, a total of 320 urban scenarios were considered derived from the combination of different orientations and inclinations of the tilted plane, and different orientations and aspect ratios of the urban canyon. Models were evaluated against the diffuse irradiance values obtained by the ISO 15469:2004(E)/CIE S 011/E:2003 model and radiance measurements performed by a sky scanner at the radiometric station of the Public University of Navarre (Spain).