Photovoltaic panel integrated with phase change materials (PV-PCM): technology overview and materials selection

In recent years, the utilization of phase change materials (PCMs) in photovoltaic (PV) module for thermal regulation has attracted wide attention in this field, as the hybrid PV-PCM technology can not only achieve higher photoelectric conversion efficiency but also make it possible to extract thermal energy stored in PCMs for cascade utilization. Although substantial research has been carried out on PV-PCM systems, the promise of practical application is still far from clear with some barriers unsolved, such as PCMs which need further improvements in both technical and economical view. In this paper, a comprehensive literature review of the state-of-the-art aspects of PV-PCM systems is presented, with the focus on technology overview and materials selection. The concept of hybrid PV-PCM system is first discussed with its general configuration and energy balance, to figure out the key factors affecting its performance. Besides, the development route of PV-PCM research is outlined through a comprehensive review of 104 research articles during 2004-2018, clarifying the representative achievements and existing problems in each stage. Furthermore, PCMs are highlighted in this paper with details on their classification, properties, and application in previous PV-PCM research. In particular a triangle about materials selection criteria and determination strategy of phase transition temperature is proposed. Finally, the challenges and prospects of future research on PV-PCM systems are raised, advocating that more attention should be addressed on new strategies to overcome the existing problems such as insufficient reliability and economic feasibility.