An exploration of the impact of fixed shading device geometry on building energy performance

Building systems account for 71% of energy used in buildings (USGBC). Researchers have explored solutions for reducing energy use in buildings. One way to minimize energy use is by reducing cooling loads through use of shading devices. This research explored the impact of fixed shading device geometry on energy. The research examined the role of shading device geometry including projection, width and height above window in reducing energy use. Researchers used Carrier HAP software, applied to a case study project in Northern Italy to conduct energy analyses. Researchers developed a single space model studying 376 shading device geometries on four different window configurations. A total of 1504 simulations were run in order to select an optimum for the case study. The optimum shading device was applied to a whole building analysis to determine impact on an entire building against a baseline case without shading devices. In order to help test the results researchers ran simulations in three additional locations including Spain, Italy and Germany. The study showed that fixed shading devices have a positive impact on improving building energy performance, particularly on reducing cooling loads. Negative impacts that shading devices may have on energy use in heating months can be more than offset by cooling season savings. Effectiveness of shading devices is closely related to window configuration and building thermal mass. Recommendations are made regarding use and geometry of shading devices.