Numerical Simulation of Nanofluid-Based Parallel Cooling Photovoltaic Thermal Collectors

A novel hybrid cogeneration system based on a parallel-cooled photovoltaic/thermal (PV/T) module is presented in this paper. The temperature of the parallel-cooled PV/T module is more uniform due to the parallel cooling fluid of air mixed with water or nanofluids (SiO 2 , CuO, Ag, and Al 2 O 3 ). The results show that the overall temperature of the PV cell in the parallel-cooled module is about 2 K lower than that in the single-cooled module, with a 9.01% improvement in thermal efficiency and a 0.09% enhancement in electrical efficiency. The PV/T module with nanofluid shows a significant improvement in thermal and electrical efficiency. The thermal and electrical efficiencies of the parallel-cooled PV/T module consisting of Al 2 O 3 nanofluid and air are 89.21% and 9.84%, respectively. Compared with the non-nanofluid parallel cooling scheme, the cooling method consisting of 1 wt%, 3 wt%, or 5 wt% Al 2 O 3 and air, the thermal efficiency of PV/T was improved by 5.47%, 5.30%, and 3.93%, respectively with the solar radiation of 800 W/m 2 and the flow rate of 0.10 m/s, while the electrical efficiency was improved by 0.026%, 0.027%, and 0.034%, respectively. In addition, when the solar radiation is 1000 W/m 2 with a flow rate of 0.025 m/s, the air-water parallel cooling PV/T module achieves a maximum exergy efficiency of 11.74%.