Thermodynamic study of improved cooling in solar photovoltaic cells using nanofluids with graphite-doped titanium dioxide and aluminum oxide

Maximizing energy collection and optimizing the performance of solar photovoltaic cells (SPVCs) is essential for the day. In this context, using nanofluids of graphite-dopped titanium dioxide (G-TiO 2 ) and aluminum oxide (G-Al 2 O 3 ) in SPVC systems plays a crucial role in preventing PV panel overheating, thereby enhancing electrical efficiency and the panel's life span. For this purpose, the ultrasonication technique was used to dope graphite with TiO 2 and Al 2 O 3 and mixed with deionized water (DI-H 2 O) at concentrations of 0.5, 0.6, 0.7, and 0.8 % by vol. The results indicated that G-Al 2 O 3 seems to give optimum results compared to G-TiO 2 . With G-Al 2 O 3 the electrical and thermal efficiencies were increased to 16.2% and 27.2%, this is about 5.1% and 6.3% higher than the DI-H 2 O. With nanoparticle volume concentration of 0.7%, G-Al 2 O 3 causes a 3% higher pressure drop, 3.6% higher in friction factor, 8.6% higher in Nu, and 9.5% higher in temperature gradient (ΔT/Δx) in comparison to G-TiO 2 at 14 hrs respectively. Hence it can be recommended that, with an increase in pump efficiency or by the use of a variable-speed pump, the extra resistance can be compensated for without excessive energy consumption.