Amelioration of thermodynamic performance and environmental analysis of an integrated solar power generation system with storage capacities using optimized ternary hybrid nanofluids

The optimization of heat transfer fluids as cooling agents in solar technologies have gained significant attention, especially with the groundbreaking achievements in nanofluid synthesis and practical utilizations. The synthesis of hybrid nanofluids has shown improved thermal performance in their application as heat transfer fluids in parabolic trough systems. However, the lack of clear understanding regarding the behavior of ternary hybrid nanofluids, (especially with their unique particle type behaviors) hinders further improvement in these systems. In this study, the performance of an integrated solar parabolic trough system is investigated using eight water based-ternary nanofluids with different operational conditions. This study is also carried out to estimate the potential of designing a smaller solar collector that can produce optimal performance by using ternary nanofluids as an alternative to water. From this study, it was estimated that the maximum exergy efficiency of the ternary nanofluid 1 (ZnO-Al2O3-SiO2), 2 (Fe-Cu-Ag), 3 (Fe-Cu-ZnO), 4 (Fe-Cu-MWCNT), 5 (Ag-Al2O3-TiO2), 7 (FeMWCNT-TiO2), and 8 (Fe-Graphene-TiO2) gave values of 69.07%, 66.23%, 66.74%, 66.35%, 68.04%, 69.08%, 67.74% and 68.32% respectively. The MWCNT - Al2O3 - TiO2 (ternary fluid 6), ZnO - Al2O3 - SiO2 (ternary fluid 1), Fe -Graphene - TiO2 (ternary fluid 8), and Ag - Al2O3 - TiO2 (ternary fluid 5) gave the highest useful heat measured as 15,859 kW, 15,858 kW, 15,679 kW, and 15,614 kW respectively. As compared to water, the solar collector's area can be reduced up to 30.45%, 27.66%, 28.17%, 27.76%, 29.46%, 30.48%, 29.18%, and 29.74% for the ternary fluid 1, ternary fluid 2, ternary fluid 3, ternary fluid 4, ternary fluid 5, ternary fluid 6, ternary fluid 7, and ternary fluid 8 respectively. The maximum CO2 emission of 3826 kg avoided was recorded for the ternary fluid 6. The ternary fluid 6 (MWCNT-Al2O3-TiO2) also showed the optimum energy efficiency, exergy efficiency and heat storage capacity.