Solar transmittance analysis of different types of sunshades in the Florida climate
Solar shading devices are an integral part of any building enclosure that impacts the building efficiency and indoor environment especially in the hot and humid climates like Florida. In order to design an energy efficient structure, the solar transmittance of the window-shade system needs to be determined in order to calculate how much total solar radiation they transmit. This paper presents the findings of a comparative study for evaluating the effects of different solar shading devices on the solar transmittance properties of windows with different orientations in the city of Miami, Florida. A rectangular office block was modeled and rotated clockwise in 60° interval from North to South to study the variations in the transmission properties of windows. Commercially available shading products were analyzed under three broad categories, i.e. external, interpane and internal and each type was simulated with six different orientations: North (N), Northeast (NE), Southeast (SE), South (S), Southwest (SW), Northwest (NW). The climatic data file was produced by the software METEONORM. The simulation results were compared to determine a performance metric for the primary and the total solar transmittance of each window-shade system. After selecting the most efficient solar devices, a thermal analysis was performed to estimate the reduction in cooling loads generated by improving the internal operative environment.