Conventional fixed shading devices in comparison to an electrochromic glazing system in hot, dry climate

Electrochromic glazing or exterior shading devices offer shading of the intense direct sun, reduce glare, and improve the daylight luminance within buildings. Additionally, they are important factors affecting energy performance of buildings as they impact the heating and cooling consumption. This analysis investigated the performance and the effectiveness of electrochromic glazing to prevent unwanted solar heat gains from entering a conditioned space. Then, these performances are compared to those offered by conventional fixed exterior shading devices in identical conditions. The aim of this analysis is to provide architects and designers with general guidance and appropriate design strategies for different window treatments and shading techniques during early design stages in hot, dry climate. A typical office building is modeled using DesignBuilder software. Building envelope characteristics, internal loads, and operating schedules including schedules for equipment, occupancy, interior lighting, heating, ventilating, air conditioning, and weather data are all unchanged throughout the simulation process. The windows shading condition and the glazing type are the only varying parameters. The output data show that electrochromic glazing provides the best performance in reducing solar heat gains compared to other tested shading conditions.

► The impacts of solar control devices are different depending on various external and internal load conditions.
► Electrochromic glazing system shows the best performance among all tested alternatives.
► Exterior shading devices offer potential to reduce building cooling load demand and mechanical equipment size.