A study of salt gradient solar pond in the tropics

Abstract

Paper presented to the 10th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Florida, 14-16 July 2014.The energy generation potential of a salt gradient solar pond in Ile-Ife, Nigeria (7°28’13.41”N, 4°32’50.82”E), a tropical environment was experimentally determined from a laboratory scale model in this investigation. The laboratory scale model solar pond was constructed from a rectangular plastic tank with a cross- sectional dimension of 0.98m x 0.8m and a height of 1.0m. The salinity gradient was achieved using the salinity redistribution method. Measurements of the temperature at depths of 0.2, 0.45, 0.75, 0.85 m from the base of the pond and ambient temperature were taken using type K thermocouples. Global radiation were taken during a period of 21 days of experimentation using a global radiation meter (Model GRM 100). Results from solar radiation measurements showed that the average global radiation for the period of experimentation was 398.3 W/m2. A comparison between the temperature profile obtained experimentally in the model pond and that obtained from theoretical relations showed good agreement. Theoretical determination of the available thermal energy collected in the experimental pond showed that the thermal energy obtainable from the pond was 24.3MJ. Results from the investigation shows that the utilization of the salt gradient solar pond technology could improve the energy access problem in the rural areas of Nigeria.