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This Tower Pulls Drinking Water Out of Thin Air

smithsonianmag.com

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Re: This Tower Pulls Drinking Water Out of Thin Air

#11

Post by shadowmint »

Here's a link that describes the technology behind it: http://newsoffice.mit.edu/2013/how-to-get-fresh-water-out-of...

...and one showing the structure in detail: http://www.architectureandvision.com/projects/chronological/...

TLDR: Great for pulling moisture out of the air if the air already has a really high moisture content. Pretty much useless in other circumstances.

Re: This Tower Pulls Drinking Water Out of Thin Air

#13

Post by notahacker »

ghshephard wrote: post #8
meric wrote: post #6

Earlier quoted context omitted.

I think it takes more than just money to setup the towers. The article mentions maintenance is a big problem for imported solutions, so they'll need to teach locals on how to maintain/build the tower. There aren't too many people who knows enough to build such a tower, so they cannot simply spend $500 * 1000 to get towers for 100 villages, since they need to first teach people to build it and second teach people in e…

Everything in the article suggests that this is something that can be done locally: "If the many failed development projects of the past 60 years have taught us anything,...it's that complicated, imported solutions do not work." "inexpensive, easily-assembled structure that extracts gallons of fresh water from the air. " "The structures, made from biodegradable materials, are easy to clean and can be erected without…

Add in the insight that the project was launched in 2012, and the erection itself apparently takes four people a week[1] and you have to wonder why they're so unambitious. I'd speculate that might be down to it requiring very specific local condensation conditions to function with the claimed efficiency, but there's a long and mostly disappointing history of trying to create drinking water from air[2]

[1]http://inhabitat.com/nature-inspired-warkawater-towers-use-c...

[2]https://en.wikipedia.org/wiki/Air_well_%28condenser%29

Re: This Tower Pulls Drinking Water Out of Thin Air

#14

Post by stcredzero »

GlennS wrote: post #12
patchhill wrote: post #10

Are these not powered? How do these things overcome the laws of thermodynamics?

They are effectively solar powered, since they rely on a temperature difference.

Ubiquitous electrical outlets cripple 1st worlder understanding of physics. Film at 11.

Re: This Tower Pulls Drinking Water Out of Thin Air

#15

Post by zmguy »

I don't agree with not having local repairmen as being a real showstopper. Any new system requires training: fire building, hut building, brick making. They need to factor training into the roll out of the technology, and don't focus on training men, take the women and grandmothers, train them first. RE: The barefoot movement in India: http://www.ted.com/talks/bunker_roy Tell a mother she doesn't have to walk 6 hours for dirty water, she will learn to fix whatever is necessary given the right training and availability of tools/material.

Re: This Tower Pulls Drinking Water Out of Thin Air

#16

Post by bryanlarsen »

shadowmint wrote: post #11

Here's a link that describes the technology behind it: http://newsoffice.mit.edu/2013/how-to-get-fresh-water-out-of... ...and one showing the structure in detail: http://www.architectureandvision.com/projects/chronological/... TLDR: Great for pulling moisture out of the air if the air already has a really high moisture content. Pretty much useless in other circumstances.

According to the article, it's temperature differential that's important. So it works in the desert, which has 50 degree swings between day and night. Many places with high moisture content have much smaller swings in temperature, so it might not work as well in the jungle.

Re: This Tower Pulls Drinking Water Out of Thin Air

#17

Post by linhat »

Isn't the generated/collected water like condensed water free of any kind of salts etc. that would naturally occur in ground/drinking water, so shouldn't it be unsafe to drink large amounts of it (much like it is unsafe to drink large amounts of salt/sea water due to the saline imbalance)?

I wonder how/if they address this?

Re: This Tower Pulls Drinking Water Out of Thin Air

#20

Post by zhte415 »

ghshephard wrote: post #5

Something doesn't seen internally consistent in this article. We read about a device, that can be locally assembled, that, can draw up to 25 gallons of water a day (I would have been impressed with 1 gallon a day) - and, "In all, it costs about $500 to set up a tower...His team hopes to install two Warka Towers in Ethiopia by next year and is currently searching for investors who may be interested in scaling the wate…

Making a physical product that may have to be tailored to varying specific requirements could be difficult, meric above mentioned technology / skill transfer where an assumed solution may not have an optimal effect, or be even be disastrous - I'm sure they're honing an experience set and training and maintenance manual.

Sewage works may be a tangential example. Many sewage treatment plants basically work by sifting heavy material, then using aerobic bacteria to break down dirty water, and anaerobic bacteria to break down the aerobic bacteria (resulting in manure slosh) [a heavily simplified version]. But each plant has varying PH and mineral levels, meaning optimal bacteria are often designed for specific plant locations, and the specialist knowledge required can be very deep.

I see nothing wrong with going it slow, and documenting carefully in a very hands-on way, any hiccup and both 'known unknowns' and 'unknown unknowns' that may be overlooked in a mass roll-out.

[Edit: typo]

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