Experiment study of the effect of salt on the stability of solar ponds

Abstract

The sun is the largest source of renewable energy and this energy is abundantly available in all part of the earth. One way to trap solar energy is through the use of salt‐gradient solar ponds (SGSP). Collecting and storing of energy for this device is in one system, so the heat in summer can be utilized in winter. A typical SGSP consists of a pond containing three density stratified layers. The stability duration and the efficiency of a SGSP depend closely on the self‐maintenance of the NCZ layer, which itself depends on the type of the used salt. This article reviews nonconvective solar ponds, the problems encountered in their operations and the effect of the used salts. Three salts: NaCl, MgCl, and CaCl2 were tested in a laboratory set‐up under different operating conditions. Temperature and concentration gradients were developed by heating the pond from the bottom. The results showed that MgCl and CaCl2 stratification remains stable until the temperature reaches around 70 °C while NaCl layers were mixed at 55 °C. © 2018 American Institute of Chemical Engineers Environ Prog, 38: 699–705, 2019

Advances in solar pond technology and prospects of efficiency improvement methods

“…Gel solar ponds present several advantages, including reduced surface evaporation and heat loss (El-Housayni & Wilkins, 1987), low maintenance due to the absence of a salt gradient (Sayer et al, 2018), decreased costs and environmental concerns from minimal salt use (Ines & Jomâa, 2019), and enhanced heat storage from the gel's insulating properties (Spyridonos et al, 2003). However, the major drawback of gel ponds is the high cost of gel production for commercial-scale ponds (Kasaeian et al, 2018).…”