Paper Title
Potable Water Resources – Efficacy Of Solar Still Design

Abstract
Abstract - To address the decreasing access to potable water resources the efficacy of three categories of single basin passive solar stills were investigated. The single slope double basin still proved to be the most efficient, reaching a high of 13.61% on the clearest test day. This was 1.83% and 9.3% higher than the double slope single basin and single slope single basin stills, respectively, under the same climatic conditionsand similar construction. The higher productivities lies with the design that captures some of the latent heat lost from condensation and reuse it to produces more distillate. The results showed that this system produces more than three times the amount of distillate compared to the conventional still. The double slope single basin solar still showed an efficiency high of 11.78%, which is 7.47% higher than the conventional still on the clearest day. The greater efficiency and productivity yields was due to the double glazing design. The north facing glazing showed lower daily temperatures, than the south, thus facilitating greater productivity yields during the course of the day. The single most important parameter that affected the efficiency and productivity of the solar stills is the solar radiation intensity. High percentages of cloud cover tends to negatively affect the diurnal productivities since it reduces the global solar radiation intensity and thus the solar energy received by the collectors. The wind velocity also impacted on the productivity of the stills such that higher temperature differences between the glass and the water are achieved as wind velocity increase thus increasing productivity. Keywords - Potable Water, Solar Still, Clean Water Resources, Distillation