What is the best way to extract condensation from Desert Air ?

Question

Years ago i saw on TV a device that was a bit like an umberella and it collected moisture because of the temperature difference at night. The water was collected at the base, anyone got any idea if this sort of device is being used?

Answer 1

This is a desert still, and can be made in several ways.

Usually, a hole is dug in the sand, and a plastic sheet placed over the hole and secured around its edges.  Then a stone is placed in the centre of the sheet, so that it hangs down over the hole like an inverted cone.

What happens is that the sun draws any moisture out of the sand, because the sheet traps heat like a greenhouse.  Then at night, the cooler air causes the water vapour in the air inside the hole to condense on the underside of the sheet, and run down the cone; to drip into a container placed at the bottom.

Usually, there is not enough moisture in the sand to make the exercise worthwhile, so some moisture containing material (leafy branches cut up, for instance) is placed in the hole to provide a source of moisture (and the natural transpiration from the leaves helps, as well).

Any source of water can be used, such as salty water that is unfit to drink, or even urine.  The water collected in the still will be pure.

You might need several sheets; because one might only produce half a cup of water a night.

Answer 2

I wouldn't think there would be much moisture in the air at all, espeically not to collect any tangible amount, but interesting nonetheless...

sorry i can't help