Whole building energy simulation with complex external shading devices

In this paper an approach for pre-calculating building façade incident irradiance levels under a typical, yet computationally complex, external shading device with state-of-the-art ray tracing simulation techniques is presented. The impact of accurate modelling of direct solar, diffuse sky and inter-reflected irradiance components on resulting levels of thermal comfort and energy demand is analysed and recommendations are given for improvement of modelling capabilities.