I looked at your link, and one thing I noticed is that the site claims that these devices can be powered entirely from desert heat...quite impressive...
The trouble is though, is that only around 0.004% of the world's water is contained in the atmosphere. Over 77.20% is in the polar ice caps, but I dread to think of the practical costs regarding pumping fresh water all over the world!
Groundwater has the second most, with 22.26% of reserves, and significantly below this are the rivers and lakes, with 0.32%, and then soil.
I think the real advantage with what you propose though, is that moisture can be extracted as fast as one wants it, and there is no need to carefully moniture the extraction rates.
What we need is to compare the cost of desalination with the cost of groundwater extraction, and extraction from the atmosphere, and if possible, from glaciers and ice-caps. (Though this last one seems a bit unrealistic).
Somehow, we then need to take countries which do have water shortages and are very poor (we know that a rich country can afford desal), and see how much water they are lacking/could do with. (A few examples where water wars/ brikmanship have taken place would be between Angola, Botswana and Namibia, Israel and Egypt, Egypt and Ethiopia, Syria and Turkey, Jordan and Saudi Arabia, India and Bangaldesh, Libya and Egypt etc.
Thankfully, Qaddafi's ingenious irrigation schemes, such as his man-made river project, are going to lessen the impact of continuing popualation growth, at least for Libya.
"In general a country with less than 1,700 cubic meter per capita is regarded as experiencing water stress, while less than 1000 cubic meter is regarded as water shortage."
According to:
WaterWars
The next bit is according to:
Statistics that show water availability in each country:
So, as we can see, all the countries below China have water stress, and all the countries from Uganda downwards have a water shortage. Now someone who doesn't mind doing maths needs to calaculate how much it would cost for each one of them to make up the extra amount, fistrly if they were to use Desal, and then with the other methods. It costs 40 cents per cubic metre to desal. I'll take an example of one country that not only has severe shortages, but also has a chance of starting a war over it:
Namibia:
Would require an extra 1701.94 thousand cubic metres. So, using desal, they would have to fork out about $71,607,760
That's
alot...
