Development and validation of a numerical heat transfer model for PCM glazing: Integration to EnergyPlus for office building energy performance applications

Glazing filled with Phase Change Materials (PCMs) or PCM glazing arises as a strategy to improve the office buildings’ energy performance by providing thermal inertia to glazed façades. PCM glazing can reduce office buildings’ cooling energy consumption in warm climates. Literature shows a good understanding of PCM glazing thermophysical properties. However, nowadays, it is unfeasible to estimate the energy consumption of offices with PCM glazing based on annual energy simulations. Therefore, this paper aims to integrate a novel, developed, and validated PCM glazing heat transfer model for building energy performance applications into EnergyPlus. In order to do this, a numerical heat transfer model of a double-clear glazed filled with PCM based on literature is developed. This model is validated experimentally and integrated into EnergyPlus, a state-of-the-art building energy simulation tool. Annual simulations are carried out for an office room with different WWR, façade orientations, and PCMs in four climate conditions to show the model’s capability to estimate the energy consumption and cooling peak load reductions. The results show that double-clear glazing filled with PCM can reduce the energy consumption of an office building up to 9.1 % and reduce the cooling peak loads up to 10.5 % compared to the same office building with a triple-clear glazing filled with argon. The best results were observed in warm climates with significant diurnal temperature variations.