In recent years, substantial efforts have been focused on innovating the design modification of water heating systems to overcome the issue of low efficiency. This study evaluates the performance of four different cases of evacuated tube solar water heater (ETSC). conventional ETSC, ETSC with wavy tape, ETSC with PCM, and lastly ETSC with PCM + wavy tape. The novelty of this research lies in exploring the integration of binary eutectic PCM and combined effects of PCM and wavy tape in the operation of ETSC. The findings of the present study reveals that the enhancement in outlet temperature in ETSC with wavy tape, with PCM and, with PCM and wavy tape is 7, 9.7 and 12 % respectively as compared to conventional ETSC. The highest hourly efficiency had noticed 71.75% for the ETSC with (PCM + WT), followed by 67.63%, 65.5%, and 60.61% for the ETSC with WT, PCM, and conventional, respectively while the daily average efficiency of the discussed cases is 35.17, 39.90, 40.32 and 45.92% respectively. Similarly, the exergy efficiency follows the same trend as energy efficiency and reveals that the ETSC with (WT + PCM), exhibits an average exergy efficiency of 6.11%, which is higher than conventional ETSC (3.48%), ETSC with plain WT (4.43%), and ETSC with PCM (5.09%). The environmental analysis based on energetic and exergetic approach is also carried out and the results reveals that ETSC with PCM + WT mitigates more CO ₂/ton compared to the other cases.