Utilising Latent Thermal Energy Storage in Building Envelopes to Minimise Thermal Loads and Enhance Comfort

Given exterior walls as the main drawback of buildings, the present experimental study was conducted to investigate the effect of phase-change material (PCMs) as the building envelope layer on the thermal effectiveness and indoor air conditioning. Two 1 x 1 m(2) cubicles with the same geometry, orientation and construction materials were built as an experimental set-up while adding a PCM layer to the walls of only one of the cubicles referred to as the PCM cubicle and leaving the other wall layers unchanged. The other cubicle is referred to as the Ref. cubicle. Several K-type thermocouples were mounted within the layers at the centre of both cubicles. The same air cooler used to match the indoor conditions of the two cubicles at the beginning of all the examinations was shut down after achieving the desirable temperature at their centre to allow the environment to naturally change the indoor conditions of the cubicles. The indoor cubicle temperature as well as temperature at the interface of layers are acquired. The data collected within nine days respectively showed reductions of 1.5 and 2.3 degrees C in the average and peak indoor air temperature of the PCM cubicle in summer compared to those of the Ref. cubicle. Using the PCM panel in the eastern wall (hot wall) also decreased the heat gain by 44%.

Automated summary

This experimental study found that using phase-change material (PCM) in the exterior walls of buildings can significantly improve thermal efficiency, reduce indoor temperature variations in summer, and decrease heat absorption.