EXPERIMENTAL INVESTIGATION AND PERFORMANCE EVALUATION OF STEPPED SOLAR STILL WITH ETC COLLECTOR

Solar distillation has been used for many years, usually for comparatively small plant outputs. Over the years, substantial research has been carried out to find out ways into improving the efficiency of the process. In meeting the challenges of the provision of potable water for drinking and sanitation, huge desalination plants have been built. The introduction of dual-power plants were also deployed to reduce the cost of electricity and water which could impact negatively on the populace. Exhaust heat from power plants were also deployed as an alternative for running desalination systems. These are large desalination systems though. However, not all water demands are coupled with the need for additional electric power. Solar energy may be deployed to produce fresh water from the sea. This may be accomplished in a large system or in a simple basin-type solar desalination unit. On a practical basis, certain things ought to be taken into consideration while designing and operating a solar still. For instance, shallow basins require large expanse of land. This can reduce the overall absorption area of the basin, thereby impacting negatively on the effective basin area. Leakage can cause distillate to leak back into the basin or even leak out of the basin. It is equally necessary to flush the still basin on a regular basis so as to remove accumulated salts and microbes that might have grown in the brines. The use of algaecides might also be encouraged to control the growth of algae. The heat transfer processes in the solar still are all dependent on the difference in temperature between the brine surface and the glass. The higher the difference, the greater is the energy transfer rate by each mechanism. Furthermore, the higher the brine temperature, the greater the proportion of energy usefully transferred by evaporation. In this paper, the Solar still equipped with phase change material (PCM) is designed and fabricated to improve the daily yield and efficiency of the still..