Desalination of the brackish water using a passive solar still with a heat energy storage system

Desalination of the brackish water using a passive solar still with a heat energy storage system put under the basin liner of the distillation device is dealt with the help of transient mathematical models. Phase change materials (PCMs) are used to store energy in the process of changing the aggregate state from solid to liquid. The energy balance equations for the various elements of the still as well as for the PCM are formulated and numerically solved. In meteorological conditions taken on 15th of June 2011 at the Errachidia city (Latitude: 31°58′N, Longitude: 4°20′W), Morocco, numerical calculations have been carried out for three kinds of PCMs which have different melting temperatures. To validate the simulation results, the brackish water temperature is compared with the analytical expression and the existing results in the literature. The obtained results show that the excess energy produced during sunshine times is stored in a PCM for use later during the night. Moreover, it is highlighted that the choice of the phase change material (PCM) depends closely on the maximum of the brackish water temperature that can reach by the brackish water in the basin.