There are several ways of making water safe to drink. Filtration, treatment by chemicals or sunlight (SODIS) or some kind of solar still distillation. We will focus mainly on solar stills as these allow us to change and control variables.

Solar Stills 

There are many ways of producing solar stills . They all depend on heating water in one area to evaporate it and cooling it in another to condense it and then collect the distillate.

There is a great deal of scope for innovation,

Some ideas are shown, but which one works best and under what conditions?

 

A more complex design

Will you get more from plants and a plastic bag?