In this study, three experiments are used to heat the water. In the first experiment, a simple evacuated tube collector solar water heater (ETCSWH) was used to measure the water temperature. This served as the baseline measurement, allowing an understanding of the natural heating efficiency of the system under standard conditions. In the second experiment, a flat plate reflector (FPR) was placed beneath both evacuated tubes. The idea was to make sure that part of the sunlight would reach the reflector after falling on the tubes. The exposure to solar radiation surrounding the tubes would then increase as the reflected radiation returned to them. The water heated up faster as a result of the improved heat absorption. To examine how the reflector affected the system’s thermal performance, the water’s temperature was recorded. In the third experiment, the FPR and twisted tapes (TT) were placed into both tubes. By raising turbulence inside the tubes and improving absorption of solar energy through reflection, the combination sought to improve heat transfer. To assess the system’s thermal performance under these altered circumstances, the water temperature was measured. This causes a significant rise in water temperature compared to the previous two experiments. The use of a FPR improves the efficiency of the system by utilizing the otherwise lost radiation, making the heating process more effective. The lower portion of the evacuated tube (ET), which remains in contact with the earth’s surface, receives significantly less solar radiation. As a result, the water inside this section of the tube does not heat effectively, leading to uneven temperature distribution. The thermal efficiency of the first experiment, which includes a twisted tape, and the second experiment, which incorporates both a twisted tape and a flat plate diffuse reflector, is 9.5% and 15% higher, respectively, compared to a simple ETCSWH.