Optimizing the performance of solar water heater energy storage system using phase change materials

Phase change materials (PCMs) can be used in solar water heaters to store excess heat energy available during sunny hours. The purpose of this study is to investigate the performance of the solar water heater system with heat pipe, along with the energy storage system containing phase change materials (PCMs). In this study, a cylindrical galvanized tank with double spiral coil and containing PCM acts as a thermal energy storage unit. Paraffin is used as PCM and water is used as a heat transfer fluid (HTF) to transfer heat from the water heater tank to the spiral tubes and from there to the energy storage tank. The charging and discharging process tests are carried out on sunny days and in real operating conditions. The importance of temperature changes of HTF heat transfer fluid and PCM phase change material as well as the range of changes have been discussed. Functional variables of charge and discharge energy and thermal energy efficiency have been studied. The calculated charging efficiency, 75.7 %and the efficiency of the energy storage unit for the discharge process was 61.1 %. PCM saved 2700 kJ of heat in 70 minutes for 80 ° C during charging and 1650 kJ of heat in 50 minutes at 25 ° C and 42 liters per minute in storage, discharge. He made energy. From the tests, it was found that PCM improves the performance of the system by increasing the charging energy efficiency and the thermal efficiency of the hot water storage tank.