Thermal performance of solar control coatings: a mathematical model and its experimental verification

The experimental validation of a mathematical model that predicts the shading coefficient (SC) and the solar rejection factor (SRF) of various types of solar control coatings is presented. The model allows us to input the solar absorptance and predict the temperature of the solar control glazing as a function of the thermal emittance (epsilon) and exterior temperature for typically AM2-solar radiation. With the additional knowledge of the solar reflectance, the SC and SRF are calculated. The model is tested using a chemically ZnS-CuxS solar control coating deposited on a 6 mm clear glass and the results are compared with those for commercial glasses.