Enhancing thermal energy and exergy harvesting in concentrated solar power systems using graphene-ZrO2/water hybrid nanofluid: An experimental study

Recent research has witnessed a significant increase in studies investigating the impact of nanofluids on enhancing the efficiency of sustainable energy systems. According to the details that were provided, the present study aims to enhance the heat and exergy efficiency of parabolic trough solar collectors (PTSCs) by using a water-based hybrid nanofluid with dispersed Graphene-ZrO2 at various volume concentrations (water, 0.05 %, 0.075 %, 0.1 %, and 0.125 %) as the working fluid. This research employs the hybrid nanofluid to improve heat transfer characteristics within the C.S.P. system, enhancing thermal energy extraction and exergy utilization. The proposed nanofluid underwent Fourier transform infrared spectroscopy (FTIR) analysis to determine its transmission spectrum across various frequencies. X-ray diffraction analysis was also conducted to elucidate the structural characteristics of two identical water and hybrid working fluids. The maximum thermal efficiency of 68.7 % was achieved for the PTSC system by adding 0.125 % of ZrO2 nanoparticle concentration with a mass flow rate of 3 L/min. Exergy efficiency was found for maximum volume concentration compared to distilled water fluid. Experimental results indicate significant improvements in thermal energy (68.72 %) and exergy harvesting efficiency (16.7 %), demonstrating the potential of graphene-ZrO2/Water hybrid nanofluids as a viable solution for enhancing the performance of C.S.P. systems.