State-of-the-art review on performance enhancement of photovoltaic/thermal system integrated with phase change materials

Solar photovoltaic/thermal (PV/T) technologies have attracted great attention and have been widely studied in recent years. Taking phase change material (PCM) as the cooling and thermal storage medium of PV/T modules is now considered to be an effective approach to improve the overall efficiency of PV. This paper is to provide a comprehensive review of recent progress in PV/T-PCM systems. The experimental and numerical investigations on the cooling performance of the PCM in various PV/T collectors are reviewed and analyzed. The multivariate/ multi-objective optimization strategies used to improve the comprehensive PV/T-PCM performance are summarized, involving the Taguchi method, response surface methodology, and genetic algorithm. By using multiobjective optimization, a better balance among energy, exergy, economy, and environmental performance of the PV/T-PCM system can be achieved. Most PCMs have the drawback of low thermal conductivity. Various heat transfer enhancement methods are employed in PV/T-PCM systems, including nano-enhanced PCMs, porous carriers, microencapsulated PCMs, fins, and system configuration adjustments. The review gives a comprehensive analysis of these heat transfer enhancement methods. The applications of the PV/T-PCM module in different fields such as building, drying, refrigeration, and desalination are also summarized. Finally, challenges and suggestions for further studies are put forward for developing the PV/T-PCM technique in terms of material fabrication and improvement, system optimization, and performance analysis.