Performance improvement of a single slope solar still by employing thermoelectric cooling channel and copper oxide nanofluid: An experimental study

This experimental study elucidates the performance of copper oxide (Cu2O) nanofluid in a single slope solar still integrated with external thermoelectric glass cover cooling channel. Four thermoelectric cooling modules (TEC) are mounted on the walls of the galvanized external channel in order to create the cool air to flow over the glass cover. Moreover, copper oxide nanoparticles with different volume concentrations are utilized. The results including difference in temperature between the water basin and glass cover, productivity of fresh water, energy efficiency and exergy efficiency of modified solar still are compared with those of a conventional solar still. The results reveal that the productivity, energy efficiency and exergy efficiency of the modified solar still are enhanced in comparison with the conventional solar still. Additionally, with adding the copper oxide nanoparticles to the basin brackish water, the productivity, energy and exergy efficiencies increase significantly with respect to the modified solar still without using the nanofluid. By adding 0.08% volume fraction of the Cu2O nanoparticles to the basin water of modified solar still with thermoelectric cooling channel, the maximum enhancement values for productivity, energy and exergy efficiencies are about 81%, 80.6% and 112.5%, respectively. In addition, the cost analysis shows that the optimum cost per liter and payback period time in the modified solar still are 0.0218 ($/L/m(2)) and 13.8 months, respectively. (C) 2018 Elsevier Ltd. All rights reserved.