Novel achievements in the development of solar ponds: A review

The concern about energy has become a severe issue in the world. The potential of using solar energy for providing the majority energy needs of human beings has caused presenting diverse technologies, which can absorb and store solar radiation. A solar pond is one of the energy devices which acts as a large solar collector to absorb and store solar radiation. The gained heat from the solar pond is considered as the low-grade heat. Therefore, improvements are needed to increase the performance of solar pond, as well as, hybrid systems to utilize this technology effectively. This study deals with the achievements in the development of solar pond in the recent decades. At first, the novel salts and additives for improving the thermal properties of the solar pond's solution are introduced. Then, the innovative designs for reducing the heat losses from the top and bottom of the solar ponds are presented. The heat extraction methods are other issues which could be upgraded. Finally, the systems, which could be hybridized with the solar pond, are discussed. In fact, in this study, the achievements in all processes for the collection of solar radiation, storing heat, extracting, and the application of solar ponds are surveyed and investigated.