This experiment investigates enhancing evacuated-tube solar collectors by combining carbon nanotube coatings with reflective mirrors. The study focuses on improving the heat absorption and retention capacity of solar collectors, thereby increasing the efficiency of solar thermal structures used for hot water production. This research investigates diverse configurations — black-painted plates, carbon nanotube-painted plates, and inclined mirrors — under extreme climatic conditions to assess their effects on water temperature and heat conservation. All enhancement techniques produced significant improvements in performance. Among the configurations examined, the carbon nanotube-painted plates produced the largest temperature increase, with temperatures reaching up to 70.88 °C. Moreover, reflective mirrors, strategically placed to maximize solar storage, produced a desirable temperature rise of up to 77.68 °C. The combined use of carbon nanotube coatings and mirrors yielded the most promising results, perfecting the temperature of hot water supplied across diverse weather conditions. This study provides strong evidence that the combination of carbon nanotube coatings and reflective mirrors can significantly improve the overall performance of evacuated tube solar collectors. These findings suggest that such advanced materials and configurations have a substantial capacity to enhance the efficiency of solar thermal storage systems, providing a promising and sustainable solution for water-heating applications in diverse environmental settings.