This paper presents the enhancement of heat transfer and analysis of thermal performance in thermal storage system. Number of phase change materials (PCM) were analysed and paraffin was chosen in this paper. PCM storage unit was designed and developed to enhance the heat transfer rate to store heat energy in PCM storage tank. PCM storage unit consist number of copper tube filled with PCM materials. This PCM storage unit has kept in well insulated storage tank called PCM storage tank. It carries minimum of 45 litres capacity of water with glass wool insulation. Copper has high thermal conductivity and hence in order to increase enhancement of heat, bundle of copper tube was used to transfer heat from solar tank to PCM storage tank, PCM storage tank receives hot water from solar tank which has integrated with evacuated glass tube collector. Solar energy absorbed and stored in PCM storage unit as latent heat. Large quantity of solar energy can be stored in day time and the heat can be retrieved for later use. The tank was instrumented to measure inlet and outlet water temperature. Flow meters were used to measure the mass flow rate at different intervals of time. Using the observed data heat transfer rate and system effectiveness were calculated.

Keywords: PCM storage unit, solar collector, thermal storage system, Copper tubes.