Abstract— Concentrating solar energy system is a potential solar thermal technology, wherein parabolic trough concentrators (PTC) are becoming growingly popular. In this research, both analytical and experiment analyses have been done. The experiment has compared with analytical results. to examine the effect of different operating parameters. Water and water-carbon nanotube (w-CNT) are used to explore the performance of PTC system. Optimum receiver diameter is found 51.80 mm for the maximum efficiency of the collector. During optimization, mass flow rate and concentration ratio are found to be influencing on the thermal efficiency and heat removal factor. Investigations show improvement in heat transfer for added nanoparticles. Heat transfer rate is better in laminar flow than in turbulent flow. After analytical analyses, an experiment has been done using water and carbon nanotube and compared with analytical results. Results show that for every 1oC increase in outlet temperature heat gain and thermal efficiency with water increase at the rate of 0.02 kJ/s and 1.6% respectively. On the other hand, for w-CNT as HTF, for every 100 W/m2 increase in irradiance, heat gain augments at a rate of 0.23 kJ/s and thermal efficiency upsurges by around 7%. Flow rate of working fluids and solar irradiance are found to have respective negative and positive impact on thermal efficiency of the parabolic trough collector.