Performance of oil-based thermal storage system with parabolic trough solar collector using Al2O3 and soybean oil nanofluid

Oil-based thermal energy storage system with solar collector has become populous due to its simple design and characteristics. Majorly, the solar-based thermal storage systems operate between 70 degrees C and 150 degrees C temperature, with one disadvantage of inability to store energy during off-peak hours. The stored energy in thermal storage can be used for the different domestic applications, such as water heating, cooking of food, boiling, etc. An effort has been made to investigate the oil-based thermal energy storage system with the potential design to achieve the higher temperature range of above 200 degrees C. These systems can be used for domestic applications such as cooking. The integrated thermal storage system has been developed using nitrate salt as phase changing material to store the latent heat. The phase change material is filled in the cavity of the oil-based thermal storage. The aluminum oxide (Al2O3) and soybean oil nanofluid in a thermo-syphon is used as a heat transfer fluid to store and transfer the sensible heat. Parabolic trough solar collector is coupled with thermal storage system. The maximum temperature of the phase change material, during the experiment, in thermal storage system was achieved up to 220 degrees C, which is the melting point of phase change material. The mathematical model for the heat transfer analysis is also developed and the results were validated with the experimental results. The various heat transfer analysis using regression analysis is discussed.