On-line application for the calculation of shadows on collecting surfaces

摘要

The calculation of radiation losses on collecting surfaces due to shadows effect of surrounding objects is a key aspect in the design process of both photovoltaics and solar thermal collecting fields. This aspect is of special relevance in small size installations located in residential areas. Even the calculations procedures involved are well known, they are complicated and need skilled planners that usually cannot be afforded within the constrained budgets of this kind of projects. Not only yearly shadow losses are calculated but also monthly averaged values, so that it is possible to use this value to reduce monthly averaged daily solar radiation values used for systems calculation. This work, presents an overlook of the application, details on the calculation procedure used, and one case example.