Energy consumption of a building with phase change material walls – The effect of phase change material properties

The use of Phase Change Material (PCM) in the building envelope is a promising technology for providing energy savings. In this study, the effectiveness of incorporation a honeycomb PCM to the walls of a retrofitted building in Ottawa, Canada is investigated in terms of reduction of heat flux through the walls. The climatic condition of Ottawa has a low air temperature of about −14 °C in the winter season. Reduction in the heat flux through the building envelope reduces the energy consumption of the building. PCM melting temperature, peak effective capacity, and the thickness of PCM layer have been varied to study their respective effect on the effectiveness of the PCM. Incorporating 1-cm thick PCM with peak melting temperature of 20 °C gives the best performance for a typical summer day with outdoor temperature varying from 15.0 to 26.5 °C. The heat gain and heat loss through the studied building walls is reduced by 41 % and 96 %, respectively. Also, the results show no further improvement in the PCM effectiveness when the thickness of the PCM layer and the peak effective heat capacity are increased beyond 1 cm and 20 kJkg−1K−1, respectively.