Simulating Switchable Glazing with EnergyPlus: An Empirical Validation and Calibration of a Thermotropic Glazing Model

Adaptive transparent building envelope technologies could play a significant role in decreasing energy use in buildings and providing a more comfortable indoor environment. In order to evaluate these potentials in an economic and accurate manner, it is essential to have numerical models and simulation tools which correctly reproduce the behaviour of such components at the building level. This paper presents and discusses the empirical validation of models for thermo-tropic glazing, a specific adaptive transparent glazing, by means of a whole building performance simulation tool, EnergyPlus. Moreover, this study highlights the differences between two modelling approaches (EnergyPlus built-in and EMS models) and experimental data. Negligible differences are noted between the two modelling approaches, even though the models do not completely agree with experimental data unless a model calibration is performed. The EMS modelling approach could be successfully extended to other dynamic glazing technologies that do not have a builtin model available in EnergyPlus, provided that an accurate thermo-optical characterisation of the dynamic glazing is available.