There is a great need for fresh water in many developing countries. Water sources from, e.g., lakes; rivers and groundwater are often brackish or contain harmful bacteria and should therefore not be used for drinking or irrigation.In this work a simple solar double sloped basin type still was connected to a solar salt gradient pond. The salinity-gradient solar pond is constructed in such a manner that the convective circulation in the pond is prohibited by making the bottom water much denser than the surface water. In doing so, the solar radiation absorbed in the deep water can be stored; the hot water from the salt pond was used to heat salt water in the stiller, at daylight and night.The tests were conducted in September and October in autumn season in Baghdad city-Iraq in 2009. The results show development in stiller productivity at daylight and larger productivity increase at night. The stiller productivity increased also with cooling the glass cover from the still outside.
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