1Department of Mechanical Engineering, Faculty of Engineering, University of Tehran, Tehran, Iran
2Department of Industrial Engineering, Faculty of Engineering, Mazandaran University of Science and Technology, Iran
3Department of Mechanical Engineering, Amirkabir University of Technology, Iran
Online published on 25 November, 2011.
Energy storage during a phase change material (PCM) is fascinating because of its high energy storage capability and its isothermal behaviour during the process. A flat solar collector system using PCM is theoretically investigated and the obtained results are compared with an experimental study. Paraffin wax RT 65 is used as the PCM in thermal energy storage (TES) systems. The considered system is also designed for using the stored energy inside the tank which contains PCM material, by circulating water through it after sunset. Because of indirect exposure of the PCM content to the sun, rise in water temperature is more considerable in comparison to the system with directly exposed PCM. In other words, this arrangement gains more thermal energy from the sun.
Eventually, four alternative systems consisting of three kinds of PCMs and one without any PCM were economically studied to show the advantages and disadvantages. The internal rate of return (IRR) of the best alternative is around 49% which is more than sufficient for a domestic water heating system.
Flat solar collector, thermal energy storage, phase change material (PCM), water heating, economical analysis
