Has Anyone Besides Me Hear of an "Air Well"?

[DennisKy]

While watching tonight's news about the drought in Texas, I was reminded of an article I once read in a Popular Science magazine from the 30's. It gave the essential details of an "air well", a large building (similar in shape to the domes highway departments store salt in) which was a condenser of water. The article made the point that, even in a desert, ambient humidity is often high enough that, given a sufficiently cool and ventilated surface, water in considerable quantities will flow. The well is constructed internally of open shells within shells, with many small protrusions to maximize surface area. The illustration showed a thing about 10 stories high. Any engineers out there familiar with this concept? I've tried a search for "air well" on iWon and Ask Jeeves, but all I seem to come up with are a lot of aviation-related sites.

[friedo]

I found this site (http://dan.willett.net/oasis/airwell.html) which has loads of info.


An interesting invention that has never been implemented on a large scale was designed in 1931 by
M. Achille Knapen. He succeeded in condensing and extracting water from warm air to irrigate
fields and vineyards in southern France with what he called, an "air well" (See U.S. patent no.
1,816,592 (http://dan.willett.net/oasis/usp1816592.html)). Looking like a 40-foot concrete beehive, it was possible to produce as much as 6,000
gallons of water daily for every 1,000 square feet of condensing surface. An airwell can be built on
practically any scale, and the wall materials can be concrete blocks, bricks or concentric hollow
shells filled with sand or earth. A small airwell 12 feet high and 12 feet across with walls 2 feet thick
can supply a generous output of daily water.

[DennisKy]

Many thanks, friedo!

[lee]

In the southern part of South America large nets were strung in the grass lands where fog often rolled but rains almost never fall. They caught enough water to help some villages not have to depend on water being trucked in.

[Johnny L.A.]

I haven't heard of an air well, but even in a desert there is moisture. Once way to get water is to build a solar still. Dig a hole in the ground about 3 feet deep and 4 feet wide. Put a container in the centre of the hole. Put a 6x6 foot clear plastic sheet over the hole and secure it with sand and rocks. Put a small rock in the middle of the sheet, over your water container. There is enough moisture to condense on the plastic sheet. It flows to the middle because of the small rock, and drips into your container. http://www.desertusa.com/mag98/dec/stories/water.html

An "air well" sounds like a neat thing.

[DennisKy]

Johnny L.A., thanks for the follow-up. I saw the same thing in my U.S. Field Survival Manual. However, you forgot one important ingredient -- you're supposed to pee into the hole in the ground first. Skol!

[SuaSponte]

I think air wells were described in Dune
Sua

[fierra]

& water stills on tatooine for the moisture farmers in Star Wars, Sua

[Johnny L.A.]

you're supposed to pee into the hole in the ground first.
Well, that is an option. You can also put plants in the hole (succulents have lots of water in them). I also didn't mention you could put a plastic tube into the container so that you could drink without disturbing the still (put the tube in before you put down the sheet).

You might also try digging for water in the outside curve of a wash. Be careful if it's been raining in the mountains. Even though it's dry where you are, there is a possibility of flash floods.

Succulents have a wet pulp that can be chewed for their moisture, but I don't know enough about them to know if they're completely safe.

IIRC, there are "fog farms" in the Andes; at least on an experimental level. There is some sort of "catcher" (plastic sheeting?) that the fog condenses on, and the water is routed into recepticals.