The present work aims at improving the performance of a glass solar still using different new absorbers (enameled sheet metal, blackened sponge, blackened gravel, clay, charcoal and quicklime) as sensible heat storage systems under the desert climatic conditions of Adrar. Most of the solar stills studied up to now are made of sheet metal with a black coating. The main disadvantage of these systems lies in their high corrosion and water contamination by the rust of the metal used and some toxic elements. Two solar stills were designed, constructed and tested in this study in order to compare the efficiencies of the different solar desalination systems. The first one is a glass solar still with sensible heat storage materials and the second one is a conventional solar still. The solar still studied was fabricated from cheap locally available glass and healthy materials. The hourly water and glass temperatures, productivity, and efficiency of the still were measured and evaluated experimentally. Moreover, a comparison between the different materials used as absorbers was carried out as well. From the results, it was observed that the system could produce 5.6 l/m²/day of fresh water; it was also found that metal was the best absorber as it exhibited the highest productivity as compared with the other absorbers. However, the maximum volume produced by the conventional solar still was only 4.88 l/m² per day. The lowest productivity, of about 1.6 l / m² /day, was observed with quicklime. In addition, physical analysis of distillate output shows that the quality of water produced is better.
Experimental evaluation of passive cooling using phase change materials (PCM) for reducing overheating in public building
