Solar water distillation systems are among the simplest water purification systems available. No filters or membranes are required, no moving parts are used, and no electricity is needed.
Solar stills have a shallow pan with a sloping glass cover. Water is directed to the pan where it is heated by the sun. The water evaporates from the pan, rises, condenses on the underside of the glass cover, and runs down its slope into a collection trough and into a clean container for storage. The contaminants left behind in the pan should be flushed regularly. Solar stills can be mounted on roofs or on ground structures.