Optimizing MWCNT-Based Nanofluids for Photovoltaic/Thermal Cooling through Preparation Parameters

Multiwalled carbon nanotubes (MWCNTs) were employed as added particles for nanofluids in this practical investigation. To identify the most appropriate nanofluid for cooling PVT systems that are functional in the extreme summer environment of Baghdad, the parameters of base fluid, surfactant, and sonication time used for mixing were examined. Water was chosen as the base fluid instead of other potential candidates such as ethylene glycol (EG), propylene glycol (PG), and heat transfer oil (HTO). Thermal conductivity and stability were important thermophysical qualities that were impacted by the chosen parameters. The nanofluid tested in Baghdad city (consisting of 0.5% MWCNTs, water, and CTAB with a sonication period of three and a quarter hours) resulted in a 119.5, 308, and 210% enhancement of thermal conductivity (TC) for water compared with EG, PG, and oil, respectively. In addition, the nanofluid-cooled PVT system had an electrical efficiency that was 88.85% higher than standalone PV technology and 44% higher than water-cooled PVT systems. Moreover, the thermal efficiency of the nanofluid-cooled PVT system was 20% higher than the water-cooled PVT system. Finally, the nanofluid-cooled PVT system displayed the least decrease in electrical efficiency and a greater thermal efficiency even when the PV panel was at its hottest at noon.