In the present work, the aim is to numerically investigate the effect of channel grooving on the energy and exergy efficiencies of a photovoltaic/thermal (PV/T) system. The aqueous suspension of biologically prepared silver nanoparticles is employed as coolant. Two-phase mixture technique and ANSYS Fluent software are used to perform simulations and inspect the influence of Reynolds number (Re), nanomaterial volumetric concentration (φ) and groove pitch (S) on the performance metrics. The considered range for the Re, φ and S was 500–2000, 0–1% and 0–1 m. The ascending trend of thermal, electrical and overall energy efficiencies with boosting φ and Re was reported. In addition, it was seen that the electrical and overall exergy efficiencies augment with boosting φ and Re. Moreover, it was reported that at Re=500 and 1000, the thermal exergy efficiency rises with boosting φ, while for higher Res the opposite occurs. Finally, the variation pattern of overall energy and exergy efficiencies was ascending-trending. The highest overall energy and exergy efficiencies were found to be 115.73% and 18.34%, respectively, which belonged to the case of φ=1%, Re=2000 and S=0.25 m.