Quantitative evaluation of thermal performance and energy saving potential of the building integrated with PCM in a subarctic climate

Abstract

This research quantitatively investigates the thermal performance and energy efficiency of the residential building integrated with nine PCMs (PCM19 to PCM27) in different cities of subarctic climate (Dfc according to Koppen-Geiger climate classification). The thermal performance was evaluated by using the concept of average temperature fluctuation reduction (ATFR), maximum temperature reduction (MTR) and discomfort hours. ATFR allowed estimating the monthly PCM performance and determining the periods where it worked the best. MTR was used to quantitatively estimate the effect of PCM on maximum air temperature reduction during different seasons (swing and summer) while the concept of discomfort hours was used to investigate the effect of PCM on human thermal comfort. Thereafter, the concept of annual energy savings was used to evaluate the possibility of using a few PCMs for the whole Dfc climate zone. Finally, economic and environmental analyses were performed to evaluate the utility of PCMs in the subarctic climate. The results showed that the residential building integrated with PCM demonstrated better performance in terms of ATFR, especially during the warm season. Based on maximum temperature reduction results, PCMs with low melting temperatures were optimum during swing season, whereas PCMs with high melting temperatures were optimum in the summer period. According to the energy analysis results, the annual energy savings for the subarctic climate were up to 10000 kWh. It was confirmed that few optimum PCMs (PCM23 and PCM24) can be used for the whole subarctic climate to enhance the energy efficiency of the building. Finally, from the economic analysis, the payback period varied from 16 to 32 years while from environmental analysis, the annual CO2 savings up to 4817 kg were obtained. Conclusively, PCMs can significantly improve the thermal and energy performance of the buildings in the Dfc region.