Performance assessment of a solar pond with and without shading effect

Abstract

In this study, we present an experimental investigation of energy distribution, energy efficiency and ratios of the energy efficiency with respect to shading effect on each zones of a small rectangular solar pond. The system is filled with salty water in order to form upper convective, non-convective and lower convective zones. A data acquisition device is used to measure and record the hourly temperatures at various locations in different solar pond zones (distributed vertically within and at the bottom of the pond, and horizontally and vertically within the insulated side-walls). A shading model is developed to gain a more profound understanding of the energy performance of the pond. The model results of the each zone are compared with and without shading effect, based on the corresponding energy efficiencies. The shading surface area of the zones does not contribute to the thermal performance of the pond but it takes place non-sunny area in the zones by shading. Thus, the efficiency of the solar pond decreases with increasing the shading area. The energy efficiencies of the inner zones with and without the shading effect for each zone in the energy analysis are specified as the average representative solar energy for each month of the year. The highest energy efficiencies for the cases of with and without shading area are found for the month of August to be: 4.22% and 4.30% for the upper convective zone, 13.79% and 16.58% for the non-convective zone, and 28.11% and 37.25% for the lower convective zone, respectively. The results confirm that the solar pond storage efficiency can be increased by eliminating the effect of shading area. Moreover, the ratios of shading effect are found to be: 0.651 at the lower convective zone, 0.279 at the non-convective zone and 0.068 at the upper convective zone. (C) 2012 Elsevier Ltd. All rights reserved.