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Water From Wind
ghostcorps recommends a writeup in The Australian by columnist Phillip Adams about a new windmill design that extracts water from air. The article gives few details of how it works, because patent protection is not yet in place, but what is revealed sounds promising. "[Max] Whisson's design has many blades, each as aerodynamic as an aircraft wing, and each employing 'lift' to get the device spinning... They don't face into the wind like a conventional windmill; they're arranged vertically, within an elegant column, and take the wind from any direction... The secret of Max's design is how his windmills, whirring away in the merest hint of a wind, cool the air as it passes by... With three or four of Max's magical machines on hills at our farm we could fill the tanks and troughs, and weather the drought. One small Whisson windmill on the roof of a suburban house could keep your taps flowing. Biggies on office buildings, whoppers on skyscrapers, could give independence from the city's water supply. And plonk a few hundred in marginal outback land — specifically to water tree-lots — and you could start to improve local rainfall."
Disclaimer: just my guesses:
1. Does this design perform better than other windmill designs (for generation).
No; conventional windmills have long been designed to extract the maximum amount of mechanical work from the air. This new windmill is not designed to do that, and works the same in any wind direction.
2. What will this do to the atmospheric conditions?
Small decrease in humidity.
3. If everyone has one....will it no longer rain?
It will still rain. The windmills couldn't possibly collect all evaporating air in a short radius. Even if they did, clouds call still blow in from over oceans and lakes.
Apology to Ubuntu forum.
Umm, any water collected by these things would end up either: (a) re-evaporating locally or (b) running into a river. In the first case, there's no net change in water distribution. In the second case, the fresh water ultimately ends up in an ocean, restoring the salinity levels.
At any rate, we've been mining huge amounts of water out of ancient aquifers for decades without worrying about ocean salinity. But that is still an insignificant drop in the bucket compared to the real impact on salinity: the massive influx of fresh water that is currently coming from from melting polar ice.
What's the mechanism that causes the air to cool?
TFA doesn't say, but there's a couple of ways it could be done. Just dropping air pressure would tend to cool the air somewhat, and that will happen on the leeward side of any airfoil moving through the atmosphere. When aircraft fly into icing conditions, the ice tends to collect on the upper surfaces of the wings where the air pressure is lower.
One other possibility is using a windmill to drive a Sterling-cycle engine. That will pump heat from one cylinder to the other, and water will condense on the cool side.
-jcr
The only title of honor that a tyrant can grant is "Enemy of the State."
1920s? Israel didn't exist from 70 AD to 1948....Do you mean the British started this in the post-Ottoman period?
Even more incidentally, one reason there were so few trees in the first place is that the Ottomans imposed a tax on having a tree on one's property at some point.
Monarchies have the silliest taxes....
SJW: a person who perceives an injustice, and while correcting it, commits a greater injustice.
I hope the parent comment was a joke, but if not, please take a look at this site:
m l
http://ga.water.usgs.gov/edu/waterdistribution.ht
The oceans contain 96.5% of the water on the Earth. The soil moisture, which is what we would like to increase, contains 0.001% of the water. Even if you doubled the soil moisture with this technique, the the oceans would still contain 96.5% of the water. The change is simply too small to register on the same scale. So don't worry about the salt balance of the oceans.
Almost all the moisture taken from the atmosphere would btw end right back in the atmosphere again, as evapotranspiration. But in the process, it would allow plants to grow.