Many research and significant worldwide efforts have been made to combat climate change. The purpose of this research was to maximize the productivity of a flat-plate hybrid collector with two kinds of cooling medium, namely water and water-based Al2O3 nanofluid. Effects of single-volume concentration (0.1%) of Al2O3 nanoparticles and four types of volume flow rates such as 0.5, 1.0, 1.5, and 2.0 litres/minute (LPM) were also examined which found that the best performance is achieved with 2.0 LPM. The experimental results found that the hybrid collector significantly depends on solar radiation, the surface geometry of the cooling channels, and the volume flow rates of the working medium. In addition, the performance of the hybrid collector improved with increasing volume flow rate. Maximum glazing surface temperature has been attained by water collector was 68.2°C, whereas water-based nanofluid has achieved its glazing surface temperature 63.8°C. As a result, the life of the solar panel has been increased significantly. This occurred because an increase in the volume flow rate increased the turbulence of the working medium, thus resulting in better performance of the hybrid collector. Besides, the results also showed that the distribution of working medium in the channel had played a major role in the heat transfer rate. The thermal efficiency was found to vary from 13.9% to 60.7% for all the four-volume flow rates of water. Similarly, thermal efficiency was attained from 16.8% to 79.4% for all the four-volume flow rates of Al2O3 nanofluid.