A lumped transient analysis of a reflector-enhanced photovoltaic system with paraffin PCM for passive thermal regulation

This article investigates a comprehensive study of a concentrated PV (photovoltaic) system with a focus on performance enhancement through an effective thermal management. A paraffin-based phase change material is placed underneath the PV to act as a passive cooling layer especially when a solar reflector is used to concentrate the incident radiation. The mathematical model is based on the energy balance equations for all the system layers and the transient heat transfer problem is solved by an explicit numerical approach. The results indicate that the reflector causes an increase of the solar input, but also a decrease of the electrical efficiency of 8.36% without PCM and 5.09% with PCM due to higher temperatures. However, the addition of the paraffin layer greatly compensates this effect, resulting in a growth in electrical efficiency of 8.77% with reflector and 5.03% without reflector. The system also has a relatively high thermal efficiency of 58.79%. With respect to the thermal behavior, the PCM effect decreases the PV temperature by 4.62%, while the reflector alone increases it by 5.05%. The further marginal increase of 1.33% in PCM temperature confirms its role to absorb further excess heat. This paper introduces a new combined framework for both solar concentration and PCM-based cooling, which has not been sufficiently covered in previous work.