I read recently about a project called EoleWater, in which a windmill (with no other energy source than wind) condenses humidity out of the air, and which works even in completely arid or desert climates (http://www.eolewater.com/). These windmills generate electricity which runs a compressor to bring air to the right temperature for condensation, and collect 20-100 gallons of water a day, depending on the humidity.

My brother and I were talking about the idea when he mentioned an idea that sounded bright to me, so I want to ask some of the more knowledgeable among you: What if wind were channeled into a funnel and down through copper tubing that would run 5-6 feet underground (where the temperature is a constant, what, 10º C?), condensing the humidity, which would collect in an underground basin?

Would the temperature underground be cool enough to condense the humidity?

How long do you imagine the tubing would need to be to stay cool if the incoming air is, say, between 20º and 40º C?

What kind of setup would best collect/channel the actual condensation?

Thanks in advance for your ideas.

Compressors generally are used to compress a gas, then it's during decompression that the air gets chilled. I don't know how to help you with straight condensation calcs, but my hunch is that the required surface area would have to be massive. Interesting, I wish you luck.