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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

#61

Post by chinpokomon »

briantakita wrote: post #46
philtar wrote: post #30

Earlier quoted context omitted.

"Hi. We're warka tower. Pay $1000 and we'll make two warka towers, one for you and one for africa. You must pick up yours* *If you fail to pick it up in X days we'll take it to Africa"

This would be a great Burning Man exhibit.

Perhaps, but I predict limited success. The article talks about being able to install these towers in a dessert and specifically talks about temperature variance, but low humidity environments would still have more lower yield. You can't make something just out of nothing.

It also seems like the fine Playa dust would be another negative. As any Burner will tell you, Playa gets into everything. I don't see any way to avoid getting Playa into the inner chamber which then would require further filtering and refinement to separate from the water.

The best use of this technology would be an environment where ground water isn't safe, but that has a high enough humidity to be able to yield a sufficient supply.

That being said, Burning Man would provide a suitable environment to push this to the extremes and see what it might be capable of. It would certainly help discover how it will break down.

Re: This Tower Pulls Drinking Water Out of Thin Air

#62

Post by shadowmint »

sitkack wrote: post #55
clhodapp wrote: post #41

Earlier quoted context omitted.

Alternately, the article is incorrect/oversimplifying. It's pretty easy to see that it is at least oversimplifying with a simple thought experiment: Suppose we were to place a Warka Tower in an airtight with a humidity of 0% (no water in the air) and with an air temperature of 120°F. Then suppose we were to drop the chamber temperature to 40°F. By all accounts, this is a huge change in temperature for a human-habitab…

Step 1, find 0% humidity, where are you going todo that where people are living? Strawman.

The point is that this is a fog harvesting device; it collects tiny droplets of water in the air efficiently. Fog is where you have > 70% (roughly) humidity, even if its only for a period of time.

Deserts have highly variable humidity, often 10-30% during the day, and great at night; maybe 50% ... but you dont get fog in deserts, or, for that matter, in many other places.

In some very specific regions, like Ethiopia, where you have misty mountainous regions; this is a useful device (see the article for the other very misty locations they talk about deploying this in).

If you put it in your backyard, you'll probably get a tiny trickle from it occasionally, unless you live in Wales.

The refrigerative water generators (http://en.wikipedia.org/wiki/Atmospheric_water_generator) can work in places with relatively low humidity; these ones do not.

Re: This Tower Pulls Drinking Water Out of Thin Air

#63

Post by shadowmint »

bryanlarsen wrote: post #16
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.

Not really; the desert temperature differential isn't really relevant afaik; it's just to drive the air down below the dew point to generate droplets. If there's already a high ambient moisture content in the air, I can't see why it wouldn't work. This is a just a structure to collect droplets, and there are plenty of those in the jungle.

Re: This Tower Pulls Drinking Water Out of Thin Air

#65

Post by clhodapp »

sitkack wrote: post #55
clhodapp wrote: post #41

Earlier quoted context omitted.

Alternately, the article is incorrect/oversimplifying. It's pretty easy to see that it is at least oversimplifying with a simple thought experiment: Suppose we were to place a Warka Tower in an airtight with a humidity of 0% (no water in the air) and with an air temperature of 120°F. Then suppose we were to drop the chamber temperature to 40°F. By all accounts, this is a huge change in temperature for a human-habitab…

Step 1, find 0% humidity, where are you going todo that where people are living? Strawman.

I believe that my argument remains a solid, semi-logical rebuttal (it does depend on some physical intuition) to the claim that we can fully trust the original article's claim that the effectiveness of the device depends only on the temperature differential at the location where it is deployed. At the very least, the claim needs to be demonstrated in the field or explained by some documented physical phenomenon before I'll completely trust it.

Re: This Tower Pulls Drinking Water Out of Thin Air

#66

Post by jmharvey »

ghshephard wrote: post #59
briantakita wrote: post #46

Earlier quoted context omitted.

This would be a great Burning Man exhibit.

Part of the playa environment would work in their favor (Cold at night, Warm in the day) - but there are two elements in the playa that would likely make these ineffective. 1. Playa Dust - that stuff gets in everything - and this water tower would be choked with the stuff almost immediately. Cleaning it would be challenge (to put it lightly 2. More problematically, the condensation tower/Air well works on the princip…

I wonder how many problems like his would also exist in a deployment in Ethiopia. Many problems seem much more complicated when you've encountered them firsthand.

Re: This Tower Pulls Drinking Water Out of Thin Air

#69

Post by midas007 »

zmguy wrote: post #15

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…

Agreed, it's probably the opposite. Folks that are struggling out of necessary tend to have respectable DIY artisans that are very resourceful and creative in the truest sense of hacker. (When you don't have much, your ability to think of creative solutions based on what you have becomes very acute.)

Re: This Tower Pulls Drinking Water Out of Thin Air

#70

Post by midas007 »

icefox wrote: post #54
sandy23 wrote: post #29

Not just Africa, there are many places in India mainly the tribal villages where the women walk for more than 3 kms to carry 10 litres of fresh water.

Heck, places in the U.S. need water, why start in Ethiopia where the trial costs will be higher?

If a prototype has been validated, go big fast with multiple concurrent efforts.

The concerning detail is that the website lists this project as 2012. [0] Perhaps they were unable to get it working?

0 http://www.architectureandvision.com/projects/chronological/...

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