Water catchment idea

I was looking at a thread here about aircatchment systems and an idea occurred to me, probably not a new one but now I am curious about it.

The Roman's built water cisterns in North Africa to catch and hold rainwater but imagine a cistern buried deep enough to be cool, even just a 55 gallon barrel. Running a fan at night to circulate the air through it, the ...crap, I just remembered deserts get super cool at night so underground would be warmer.

Anyway, the idea was to use a solar powered/battery to run a fan to circulate air through the catchment and collect moisture, might work during the day when the temp was high? Thoughts? Laughter?

I think the fan would tend to evaporate moisture, not help it collect.

Tyler Ludens wrote:I think the fan would tend to evaporate moisture, not help it collect.

After posting this I have been running it through my head and you are right if it wasn't done correctly you would lose more moisture than you collected. The solution would be to run it down an angled pipe (6" PVC?) to ensure that the air was fully chilled so that you wrung out all the moisture before it moved over your catchment basin to ensure it didn't evaporate any of your precious harvest.

Somewhere I have the math for moving air as you use when setting up dust collection in a woodshop.

This concept can work in areas that get a cold winter, followed by a humid summer.

Where I used to live in Southern Ontario, we had ground temperatures that stayed relatively cool throughout the summer. There are hot summer days when the humidity is so high, I felt like I was going to rot. My dad's well house had a constant stream of moisture condensing on the walls. In a situation like this, the fan would result in more water being gathered.

Basements in this sort of environment are prone to Summer moisture problems for the same reason. A root cellar or other pre condensing area would cool the air before it enters the basement. This could allow water to be gathered and it would help too alleviate condensation problems within the home.

How desert moss does it.

In my desert, the dew point is often around 20F. So that means that water can't be collected out of the air at any temperature higher than that. Ground temp is around 50F.

The couple mornings per summer when we get dew are weird, Weird, WEIRD!!!