Cooling pots

[JD1]

Here is a link to the design of Zeer pots that gives the dimensions you should be looking at for the 2 pots, the gap for the sand etc.

http://practicalaction.org/zeerpots

The comments underneath indicate that the sand helps to reduce the speed at which the water evaporates so I expect that if you weren't using enough sand you would need to add water on a more regular basis.

With regard to whether they would work in the UK with a milder climate, I have searched the web for 1/2 an hour and cant find any info at all. All i can find is that the higher the humidity the worse it will perform. Looks like a fairly simple project to try out and test though, I will try and have a go at some point.

One advantage of living near the coast or a river is that you won't have to use valuable drinking water to produce the effect, it may not be so good an option if you are inland with limited access to water but that's not generally a problem in the UK