The new Solector® Sun Shading Estimator is a graphical interface tool to estimate and compare thermal performance of glazing and framing systems (for curtain walls and storefronts) with various types of Kawneer solar protection devices on the façade. Those include Versoleil™ SunShades (single and multiple horizontal or vertical blades and a variety of outrigger systems) as well as the InLighten™ Interior Light Shelf and the 1600 PowerShade™ Sun Shade System.
The tool estimates the annual cooling energy savings for the selected location and input parameters, taking into account both heat transmission through the envelope sections as well as solar heat gain calculations. This includes: (i) hourly weather data for all major locations in the United States (ii) the thermal properties of the glazing, framing and remaining spandrel section, if any, and (iii) resulting direct and diffuse solar gains through the façade for every hour in the year, including the effects of solar protection devices for the selected location and façade configuration/orientation, using the Perez all-weather anisotropic sky model. The Solar Heat Gain Coefficient (SHGC) for any combination of glazing and framing systems is precalculated using THERM*/WINDOW** calculations.
The space cooling load is then calculated for each hour of the year following the heat balance approach. Two user-selected scenarios run in parallel, and the relative percentage of annual cooling energy savings for each scenario (compared to no shading on the same façade) is provided below the figures, along with average shading fractions for every working hour of each month.
This tool helps ensure that architects and designers are aware of how various design inputs and products impact the thermal performance of a space (one floor) with one exterior façade, including the effect of solar protection devices. Note that this tool, although it considers heat and solar gains with hourly climatic data for any given scenario, is intended to provide estimates for initial design considerations and cooling energy/shading ability comparisons between framing, glazing and shading alternatives on a relative basis. Kawneer understands that these are complex calculations, involving an array of variables and underlying assumptions. Absolute numbers can only be accurately predicted using advanced whole-building energy simulation tools, which do not include Kawneer sun control products in default options. Therefore, the relative percentage of cooling energy savings is presented in this graphical tool to provide a reliable and relative evaluation of different design options.
* THERM is a state-of-the-art computer program developed at Lawrence Berkeley National Laboratory (LBNL) for use by building component manufacturers, engineers, educators, students, architects, and others interested in heat transfer.
**Berkeley Lab WINDOW is a publicly available computer program for calculating total window thermal performance indices (i.e. U-values, solar heat gain coefficients, shading coefficients, and visible transmittances).
By using this tool, the user confirms that they have read the above and understand the underlying assumptions and generalizations.