Energy and exergy analysis of photovoltaic systems integrated with pulsating heat pipe and hybrid nanofluids

Solar energy is harnessed from solar radiation and converted into various forms of energy, primarily electricity. It is a crucial part of the renewable energy landscape due to its abundance, sustainability, and potential to reduce greenhouse gas emissions. Photovoltaic (PV) panels have become a critical component in the transition toward sustainable energy; however, the efficiency and longevity of PV systems are significantly influenced by their operating temperature. Excessive heat can reduce the efficiency of PV cells and accelerate material degradation. Pulsating heat pipes (PHPs), with their excellent thermal management capabilities, present a promising solution to these challenges. This paper comprehensively investigates the effect of incorporating a three-dimensional PHP into PV systems, using working fluids with varying thermal properties, namely water, graphene oxide (GO) nanofluid with three different concentrations (0.2, 0.4, and 0.8 g/L) and their mixture with nano-encapsulated phase change material (Nano PCM), forming a hybrid nanofluid, at a concentration of 5 g/L. The collected data are analyzed from energy and exergy perspectives. The findings show that using Nano PCM in the nanofluid-based PV system (at the highest concentration) produces 22.3 Wh/day, increasing the system's electrical power output by approximately 12 % compared to a PV panel with no cooling system. It outperforms the other systems studied, with the highest overall exergy efficiency of 35.4 %. The results also indicate an average improvement in first-law efficiency. Additionally, the study shows varying levelized costs of energy (LCOE) for the system cooled with different coolants.