The dynamic impact of window characteristics on shading factor and energy consumption

• We conduct tests on shading factors for different configurations and characteristics of window.
• We obtain the optimal configurations for lighting and energy performance.
• New method is proposed to investigate the dynamic shading effect of different windows.
• The dynamic shading effect of window configuration on energy consumption is considerable.

Together with the evolution of the daylight introduction into building façade systems, energy consumption assessment becomes more and more crucial to evaluate the synthetic performance. Traditional method for evaluating the shading effect was not sufficient to consider the dynamic lighting and energy performance of window configurations due to the varying sun position. In this paper, the field measurements combined with lighting and energy simulations were carried out to explore the optimization of window configurations and characteristics. The shading factors for complex configurations were inspected by field measurements conducted within a lighting sphere, as well as a scaled physical model. It resulted that the complex configurations provided higher energy performance and enough light transmission. Furthermore a new method which integrated the shading factor and solar heat gain coefficient was proposed to investigate the dynamic shading effect of different window configurations. The following energy analysis on a full size building was conducted in e-Quest for energy consumption evaluation. It predicted the considerable potential energy conservation for windows with dynamic solar heat gain coefficient, which encourages the architects to introduce the novel independent design proposal for windows.