Experimental assessment of position of macro encapsulated phase change material in concrete walls on indoor temperatures and humidity levels

Abstract This paper presents the results of experimental investigation on macro encapsulated phase change material (PCM) incorporated in concrete walls of room models in real conditions. The focus of this study was to evaluate the effect of positions (externally bonded, laminated within and internally bonded) of macro encapsulated PCM in concrete walls on indoor temperatures and humidity levels of room models. Experimental results indicated that PCM models could adjust the indoor temperature and humility levels, however, its effectiveness was found to be greatly dependent on the position of PCM in concrete walls. The model with PCM laminated within the concrete walls showed the best temperature control and was effective in reducing the maximum temperature by up to 4 °C. Whereas, the model with PCM placed on the inner side of concrete walls showed the best humidity control and reduced the relative humidity by 16% more than the control model. Therefore, it can be concluded that PCM models are thermally efficient and by reducing the relative humidity they provide comfortable and healthy indoor environment. Moreover, it is shown that the application of PCM in public housing flat of Hong Kong is economically visible with a recovery period of 11 years.