Thermal performance of a reversible multiple-glazing roof filled with two PCM

Abstract

Glazed roofs are increasingly used in modern buildings. Integrating multiple-glazing envelope with PCM as a passive solar utilization system can reduce energy consumption of building by latent heat storage. However, the traditional PCM-filled glazed envelope still has a poor thermal performance and thermal regulation as well as climate adaptability. In this work, an innovative reversible multiple-glazing roof integrated with two PCM, silica aerogel and low-e glass was proposed and a numerical study was performed to explore its thermal performance across the season in cold climate (Daqing, China). The new roof with and without low-e glass were investigated, and compared with the traditional air-filled multiple-glazing roof. The influence of melting temperature and thickness proportion of two PCM on thermal performance of the roof was analyzed. And an energy-economy comparison between the new roof and the traditional roof in full life was performed. The results indicate that the new glazed roof can provide excellent thermal performance in both summer and winter, and has the economic feasibility. Taking the traditional roof as a reference, the energy saving rate can achieve 14.08% in summer and 33.74% in winter, respectively, and the total cost is saved 217 Yuan/m2 in full life.