Enhanced thermophysical properties of organic PCM through shape stabilization for thermal energy storage in buildings: A state of the art review

Thermal energy storage using organic Phase Change Material (PCM) can play an important role in effective thermal management of the building. Organic PCM are widely utilized to regulate the indoor thermal environment of the building because of good chemical and thermal stability, high heat of fusion, and large availability in the required temperature range. However, organic phase change material suffers from problems like low thermal conductivity and leakage during phase transition which limits there applicability in buildings. Therefore, the appropriate approach of preparing Shape Stabilized Composite Phase Change Material (ss-CPCM) with high thermal conductivity and no leakage will significantly improve the thermo-physical properties and increases the applicability of the organic PCM in buildings. This review is an attempt to investigate the effectiveness of organic PCM as ss-CPCM with a specific focus on its applicability in regulating the indoor thermal behavior of the buildings. It discusses in brief about thermal energy storage in buildings, PCM with emphasis on organic PCM, and shape stabilized PCM. In details, it analyzes various porous support materials and their effect on thermo-physical properties of organic PCM. Additionally, a detailed investigation of various types of nanoparticles used to enhance the thermo-physical characteristics of ss-CPCM was conducted. The study suggests that ss-CPCM has the potential to improve the thermal conductivity, minimize the leakage, and effectively regulate the indoor temperature by reducing the peak temperature and increasing the time delay. However, reduction in heat storage capacity of ss-CPCM needs to be critically analyzed. Additionally, factors like real time studies in buildings, annual/seasonal analysis, heat management from ss-CPCM during night, and techno-economic analysis of using ss-CPCM in building envelope need to be addressed.