Exergetic performance analysis of a solar pond

In this paper we present an experimental and theoretical investigation of the exergetic performance of a solar pond (with a surface area of 4 m2 and a depth of 1.5 m) which was built at Cukurova University in Adana, Turkey. The system was filled with salty water to form three zones (e.g., upper convective, non-convective and heat storage) accordingly. A data acquisition device was used to measure and record the temperatures hourly at various locations in the pond (distributed vertically within and at the bottom of the pond, and horizontally and vertically within the insulated side-walls). An exergy model is developed to study the exergetic performance of the pond and its three zones in terms of exergy efficiencies which are then compared with the corresponding energy efficiencies. The reference environment temperature is specified for exergy analysis as the average representative temperature of each month of the year (for example, it is taken as an average temperature of 28 °C for August). Thus, the highest energy and exergy efficiencies are found for August to be: 4.22% and 3.02% for the upper convective zone, 13.80% and 12.64% for the non-convective zone, and 28.11% and 27.45% for the heat storage zone, respectively.