Moisture Is The Essence Of Wetness

April 20, 2014 8:46 AM

Architecture And Vision has used warka trees and towers made of bamboo and fabric to harvest 100+ litres of potable water from the air (video) per day.
posted by gman (38 comments total)

Some earlier work by FogQuest on harvesting water from air.
posted by fairmettle at 8:53 AM on April 20, 2014 [3 favorites]

Some earlier work by FogQuest on harvesting water from air.

I remember reading about that. Maybe in a New Yorker article a few years ago? Just like with surface water diversions, though, there would be a point where the extraction would start causing impacts as it gets scaled up.
posted by Dip Flash at 8:56 AM on April 20, 2014 [1 favorite]

Just like with surface water diversions, though, there would be a point where the extraction would start causing impacts as it gets scaled up.

Well, yes, but I think we need to start thinking more about solutions at various scales rather than a "one approach, just bigger sometimes." I suspect that using this in a city would be kind of a waste, but it could be very useful in small, relatively isolated communities. Or...

The working system was inspired by the Namib beetle, it copies it’s strategies of adapting to the climate, The small insect collects water from the desert by condensing it on it’s abdomen, where it becomes small droplets, which slide off its waterproof back, eventually reaching the mouth.

If we just start working on genetic engineering, we can avoid the towers all together....
posted by GenjiandProust at 9:10 AM on April 20, 2014 [4 favorites]

I'm super skeptical about this. Where is the video of the water being collected? Where's the science? All I see is a designer telling you it works, while showing you something pretty.
posted by MeanwhileBackAtTheRanch at 9:17 AM on April 20, 2014 [8 favorites]

Don't tell the CEO of Nestle about this.
posted by Faint of Butt at 9:19 AM on April 20, 2014 [4 favorites]

Small point of pedantry on the FPP text: from reading the Architecture and Vision website, it seems like the name is the only part of the warka tree they are using.
posted by Dr Dracator at 9:22 AM on April 20, 2014 [2 favorites]

And when they have enough, they will transform the face of Arrakis
posted by Dr. Twist at 9:42 AM on April 20, 2014 [21 favorites]

I may be misunderstanding things, but as I recall humidity is a big part of the baseline greenhouse effect that makes our planet habitable. Rising humidity is also a major components of the feedback loop in many climate forecasts. As the earth warms the air is more humid leading to more warming. This rise in humidity has lead to a measurable decline in pan evaporation rates. The pan evaporation rate is an an experiment that measures the rate at which a pan of water evaporates (well name I think).

So it is possible that large scale deployment of this technology could be used to help slow global warming. I also wonder if this technology could be used to augment hvac. I would love
To have this in my back yard if it could also be used to remove humidity from the house and water the garden.
posted by humanfont at 9:49 AM on April 20, 2014 [1 favorite]

I don't understand how this could even work. People have been trying to build passive condensers (air wells) for a long time and the results have not been great - so you should be skeptical.
posted by Long Way To Go at 10:07 AM on April 20, 2014 [2 favorites]

I'm super curious about how the word written for "warka" in the first link, "ዋርካ" (which is evidently from Amharic?), is pronounced, as I can't puzzle it out from the Wikipedia entry on the Ge'ez writing system. (Possibly it's just "warka" and that's why my googles find nothing.)

I did come across the Wired article on this while looking though:

A Giant Basket That Uses Condensation to Gather Drinking Water

posted by XMLicious at 10:22 AM on April 20, 2014 [1 favorite]

ዋርካ = (wa)+(r+schwa/nothing)+(ka). Each character has an associated vowel with it (it's an abugida, like Sanskrit or hiragana for Japanese) although there seem to be exceptions for certain sounds like the r.

Edit: looks like any consonant can be followed by schwa or nothing, though I know nothing of the rules of sentence codas/consonant clusters/vowel deletion whereby you'd decide it wasn't "warəka"
posted by Earthtopus at 10:35 AM on April 20, 2014 [2 favorites]

I would love To have this in my back yard if it could also be used to remove humidity from the house and water the garden.
posted by humanfont at 11:49 AM on April 20
I live in New Orleans. I will gladly collect all of the humidity and generously donate it to drought stricken areas.
posted by artychoke at 10:36 AM on April 20, 2014 [5 favorites]

Well, yes, but I think we need to start thinking more about solutions at various scales

Generally speaking, high scale solutions offer a much better opportunity for reducing and computing impact and for managing collateral damage than distributed ones. This should be obvious is one things about economies of scale and simple things like uniform application of best practices.
posted by rr at 10:39 AM on April 20, 2014 [2 favorites]

ዋርካ = (wa)+(r+schwa/nothing)+(ka).

Right, I see it now. I was confusing "ዋ" with "ቀ".
posted by XMLicious at 10:46 AM on April 20, 2014 [4 favorites]

Has anyone tested / verified the claims of 100L / day in any of the target regions?

I can well imagine something like this producing several liters under excellent conditions, possibly even in an arid climate, but 100L / day seems ... a bit rosy.
posted by atomo at 11:03 AM on April 20, 2014 [4 favorites]

Interesting concept, but I'd have liked to have seen it actually working. Currently it just looks like a nice art installation.
posted by arcticseal at 11:04 AM on April 20, 2014

Generally speaking, high scale solutions offer a much better opportunity for reducing and computing impact and for managing collateral damage than distributed ones. This should be obvious is one things about economies of scale and simple things like uniform application of best practices.

Sure, but it's equally true that a solution that is practical for, say a prairie in an industrialized country may not work well on marginal land in a developing country. Also, if we wait for large scale solutions to be rolled out, isolated communities may never get access to them.
posted by GenjiandProust at 11:05 AM on April 20, 2014

I'm trying to figure out how this is going to selectively harvest water, but not, the moment that your polypropylene mesh is damp with dew, isn't going to also pick up every windborn bit of dust and fluff that comes down the pike.
posted by Kid Charlemagne at 11:12 AM on April 20, 2014 [1 favorite]

The Wired comments include a lot of questions along those lines; in addition to dust there's mold spores, bacteria, insects; what are the requirements for keeping it clean and how do you do it without any special products? How will it guard against contamination from birds and animals? Will nighttime critters be attracted to the water and damage the fabric to get to it?

And is there any significance to the absence of any demonstration of their trials in the videos I've been able to find so far? Have they collected water with one of these and can they show that?
posted by George_Spiggott at 11:27 AM on April 20, 2014 [1 favorite]

How do they stop it from blowing away?

Also, something something, Toshi Station, power converters.
posted by blue_beetle at 11:33 AM on April 20, 2014 [4 favorites]

Nice title, and one that should hold impervious to Metafilter's engineers!
posted by Blazecock Pileon at 11:59 AM on April 20, 2014 [2 favorites]

"Up to 100L" is the maximum.
posted by honest knave at 12:05 PM on April 20, 2014 [1 favorite]

Here's a Smithsonian mag piece about them.

in addition to dust there's mold spores, bacteria, insects; what are the requirements for keeping it clean and how do you do it without any special products? How will it guard against contamination from birds and animals?

Isn't all that stuff also constantly falling into every natural water supply? I'm on board for the general "show us the actual scientific studies" response to this, but this just seems like nit-picking for the sake of it.
posted by yoink at 12:06 PM on April 20, 2014 [4 favorites]

Isn't all that stuff also constantly falling into every natural water supply?

The ratio of the collection surface area to the amount of water collected is huge, and it's going into a confined container. The sheer amount of contaminant and opportunity for contamination as well as the cleaning demands seem, well, worth knowing more about.

but this just seems like nit-picking for the sake of it.

If you like.
posted by George_Spiggott at 12:23 PM on April 20, 2014

Has anyone tested / verified the claims of 100L / day in any of the target regions?

Being able to count on a daily supply of 50-150 litres of water has been a lifeline for 66-year-old Artemio Alfaro and his family. ... "The fog nets mean we have practically no water costs in the winter months, it's a saving of around 60% in our cost of living," said Alfaro. - The Guardian, 2012

- note that he's not saying it will mean financial savings, it's something he's already got.

As someone who has cleaned the remains of a dead pigeon and a large amount of unidentifiable sludge out of a domestic rainwater collection setup, yes, maintenance is an issue, and probably you'd have to do it more often with one of these than with an ordinary roof+rain setup. But a couple of hours every so often - maybe once a year, towards the end of the dry season - is hardly a major time investment (doesn't need doing every year when it's rainwater). Presumably you'd want to take down the mesh occasionally to clean and, if necessary, repair it too, which isn't quite the same as a roof.

It's also important to remember that the vast majority of domestic water use is not for drinking, and so does not need to be of high enough quality to safely drink.
posted by Lebannen at 12:38 PM on April 20, 2014 [6 favorites]

This seems cool in theory, but I have a nasty suspicion that there are unstated assumptions that limit its applicability or unexamined assumptions limiting its efficiency and reliability.
posted by wotsac at 12:47 PM on April 20, 2014

This feels designed to attract investment and then sold to GE.
posted by Brocktoon at 1:09 PM on April 20, 2014

Well it certainly seems better calibrated to the local requirements and culture than the oversold, one-size-fits-all NGO feeding-frenzy that the PlayPump became.
posted by George_Spiggott at 1:20 PM on April 20, 2014 [2 favorites]

Great post and great extra links. Thanks
posted by mumimor at 1:29 PM on April 20, 2014 [1 favorite]

As the fog catcher article noted, the water doesn't have to be potable. It can be used for watering crops, cleaning, washing clothes, or cooking. The only question is whether it's cost effective.

While it's definitely not as helpful to the world as saying snarky things on metafilter, it's nice to see people are trying new methods to get water to people.
posted by happyroach at 2:11 PM on April 20, 2014 [1 favorite]

The ratio of the collection surface area to the amount of water collected is huge

This, however, is true of every single raindrop that ever fell from the sky. I think some of the people pooh-poohing this idea don't realize just how hard it is for most people in the world to secure water than anyone in a nice first-world situation would regard as "potable." If the worst that can be said of your water is that it might have picked up some wind-blown contaminants of one kind or another you're way ahead of the game in most parts of the world.
posted by yoink at 2:21 PM on April 20, 2014 [3 favorites]

People could boil it, add drops, distill it using a DIY evaporation setup... Can't do much if you don't have water to work with, though.
posted by mantecol at 2:26 PM on April 20, 2014 [1 favorite]

in addition to dust there's mold spores, bacteria, insects; what are the requirements for keeping it clean and how do you do it without any special products? How will it guard against contamination from birds and animals?

Drop some bleach in there and/or run it through a regular or solar powered UV sterilizer like you do with a regular rainwater cistern. The kind millions of people already use
posted by fshgrl at 3:06 PM on April 20, 2014

This video about the fog catchers in Peru from Lebannen's Guardian article is very interesting, and talks about the system they use there. I'd still like to see the WarkaWater thing in action, specially since I learned that, like his ancestors in the hills above Bomarzo, Vittori designed it using traditional CAD tools.
posted by sneebler at 3:12 PM on April 20, 2014 [1 favorite]

I want one of these, and some solar panels, and purple potatoes and walking-stick kale in my garden...
posted by limeonaire at 10:26 PM on April 20, 2014

Just as a point of reference whether 100L/day is feasible, you can look at a high humidity day and see how much water vapor is in the air. So at, say 90% relative humidity at 20 degrees C, you have 15.6 grams of vapor per cubic meter of air. One liter volume of water weighs 1 kg, so doing the math you're looking at processing at least 6,400 cubic meters of air per day.

If you live in a 2,000 square foot home with 8 foot ceilings, that's about the equivalent of exchanging all the air in your house six times a day. Certainly not outside the realm of possibility.
posted by backseatpilot at 8:39 AM on April 21, 2014

I only just remembered that Ethiopia was briefly part of the Italian Empire, on their second attempt at conquest. Little though it has to do with this story.
posted by XMLicious at 10:10 AM on April 21, 2014

This gets into the building and function of fog catchers; I wonder if the side bracing is necessarily required for collection; I think that perhaps some dual duty of a sun shade in the afternoon, dew catcher in the morning ....
posted by tilde at 11:40 AM on April 21, 2014