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New Solar-Powered Device Can Pull Water Straight From the Desert Air (sciencemag.org)
sciencehabit quotes a report from Science Magazine: You can't squeeze blood from a stone, but wringing water from the desert sky is now possible, thanks to a new spongelike device that uses sunlight to suck water vapor from air, even in low humidity. The device can produce nearly 3 liters of water per day, and researchers say future versions will be even better. That means homes in the driest parts of the world could soon have a solar-powered appliance capable of delivering all the water they need, offering relief to billions of people. To find an all-purpose solution, researchers led by Omar Yaghi, a chemist at the University of California, Berkeley, turned to a family of crystalline powders called metal organic frameworks, or MOFs. Yaghi developed the first MOFs -- porous crystals that form continuous 3D networks -- more than 20 years ago. The networks assemble in a Tinkertoy-like fashion from metal atoms that act as the hubs and sticklike organic compounds that link the hubs together. By choosing different metals and organics, chemists can dial in the properties of each MOF, controlling what gases bind to them, and how strongly they hold on. The system Wang and her students designed consists of a kilogram of dust-sized MOF crystals pressed into a thin sheet of porous copper metal. That sheet is placed between a solar absorber and a condenser plate and positioned inside a chamber. At night the chamber is opened, allowing ambient air to diffuse through the porous MOF and water molecules to stick to its interior surfaces, gathering in groups of eight to form tiny cubic droplets. In the morning, the chamber is closed, and sunlight entering through a window on top of the device then heats up the MOF, which liberates the water droplets and drives them -- as vapor -- toward the cooler condenser. The temperature difference, as well as the high humidity inside the chamber, causes the vapor to condense as liquid water, which drips into a collector. The findings were published in the journal Science.
Sounds a bit like a windtrap. Can sietchs and spice-harvesting be far off?
Fog collection https://en.wikipedia.org/wiki/...
Domestic spying is now "Benign Information Gathering"
I gave TFA a cursory glance only, so sorry if ghis has been answered.
How large is this thing?
And I assume the water it produces is akin to distilled water. Isn't that bad to drink?
There have been a few, let's say, shady promises about extracting water from air, mostly coupled with crowdfunding campaigns (gee, why could that be?). Those that actually delivered a product were mostly ridiculous, provided you were not one of those duped into backing it. Then it was more a reason for anger and disappointment.
Most actually never delivered. Which reminds me, wasn't Fontus due to deliver right now in April? Any backers here, did they actually deliver? Because, let's put it careful, I'd really, really love to see that!
So don't get me wrong when I don't hold my breath. I have been promised easy water from thin air before. And what has been delivered so far, if anything, was ridiculous. Either it didn't work, didn't scale past proof-of-concept scale or only worked if the humidity was high enough that rain was more the rule than the exception, rendering a system that extracts water from the air redundant: A bucket would do.
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
That means homes in the driest parts of the world could soon have a solar-powered appliance capable of delivering all the water they need, offering relief to billions of people. ... actually minimum two.
The s indicates plural, that means more than one billion
Who on earth is so stupid to believe that "a billion" people live in "deserts"?
Nevertheless a device like this might be useful in all warm/humid areas. I wonder how clean the water will stay over time, as in: can fungi grow inside of the device, can bacteria settle in it, how to keep the water sterile and the aparatus working?
There where a few other posts about technology like this in the recent years on /.
Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.
*"The device can produce nearly 3 liters of water per day..."
*"...homes in the driest parts of the world could soon have a solar-powered appliance capable of delivering all the water they need, offering relief to billions of people."
Same sentence, yet the statements are not even close to existing in the same galaxy.
That is not even mentioning that this is less efficient that currently existing systems. Bob help us all.
The physics just don't add up. At desert levels of humidity, this device would have to be a massive energy sucking monster, with huge mass air flow to even produce small amounts of water. This must be a scam of some type.
Who on earth is so stupid to believe that "a billion" people live in "deserts"?
How about the United Nations? Strictly speaking it isn't all desert but apparently well north of a billion people live in water stressed parts of the world or areas threatened by desertification.
Nevertheless a device like this might be useful in all warm/humid areas.
Maybe. The real question is how much does it cost per unit of water generated. To be useful it would have to generate a rather sizeable amount of water even to just cover drinking and basic cleaning needs.
What is the cost per unit of water generated? It doesn't matter if it works if it is prohibitively expensive per unit of water generated. If the economics of it don't make sense it will never be used at scale.
My first job was programming binary loader-lifters, very similar to vaparators in most respects.
The heat of vaporization of water is about 2,260 kJ/kg. It's the law.
So, they hooked a solar cell to a thermoelectric cooling cell. Its the same tech as those USB refrigerators. You can build a basic a basic unit for $30-40.
You say things that offend me and I can deal with it. Can you?
Great, all it needs is a $1000 solar panel and you are set, in fact screw that, just hand them the cash and let them buy a tanker of water, 1000 bucks goes a long way, be better for the environment too, no lithium/sillicon mining, no manufacturing with massive amounts of electricity never mind the transatlantic shipping or transportation, its almost the most inefficient way possible of converting energy into water.
...that really is VAPOR ware. ;)
Every single one of these type of devices has been debunked. Often they are designed by idiots that don't understand the science behind what they are working on but sometimes they're just outright frauds.
This is probably yet another one. They might as well be selling perpetual motion machines.
This is one of those things that it seems few people pause to ponder.
The desert is already a very delicate ecosystem because of it's extreme nature. While I don't doubt that it is possible to extract water from the atmosphere on a relatively large scale... what do people think is going to happen to the deserts equilibrium when that starts happening?
Frequently it is approached from an individual perspective, sure my doing X has very little effect on the environment but when thousands of people are also doing X the effect isn't nearly as insignificant.
A human only needs around 1l of water a day to survive.
You will respirate and pee away well more than 1 liter per day under normal circumstances even if you aren't in a desert and are doing nothing active. Water requirements can easily exceed that substantially if you are sweating significantly or if it is very hot.
Here the shadyness is in the reporting, to wit:
The summary and the linked article say: ``The device can produce nearly 3 liters of water per day''.
Yet the abstract says, last sentence: ``This device is capable of harvesting 2.8 liters of water per kilogram of MOF daily at relative humidity levels as low as 20%, and requires no additional input of energy.''
There is unlikely to be a full kg of MOF in the pictured device.
...do you need a droid that speaks the binary language of moisture vaporators (which is very similar to binary load lifters) to operate it?
In the end they will lay their freedom at our feet and say to us, Make us your slaves, but feed us. - Fyodor Dostoyevsky
I Muad'dib have come back
I have no idea where you're getting 300L a day. A human only needs around 1l of water a day to survive.
No, active adults need about 3L not 1L. So with this device producing about 2.8L it could sustain a single person. Things get complicated with activity levels and climate, and water in food counts towards the total.
The 1L per day figure is life raft level rationing where you are sedentary and either rescued from the sea in a few days or likely to die so additional water is unlikely to change the outcome.
water from desert air
Thought something similar had already been developed years ago and the military had some.
I have no idea where you're getting 300L a day. A human only needs around 1l of water a day to survive.
It sounds like total water usage in the west once you consider showers, toilets, cooking, cleaning, etc.
They had better have those units in the South Ridge repaired by midday, or there'll be hell to pay.
Could that become a thing if billions of people start using these?
Thunderf00t is not going to like this...
FYI, prepare to hear a lot more about various water condensing technologies. The X-Prize Foundation is launching a competition to design a unit that can produce 2000 Liters per day at total cost of $.02 per Liter, from renewable energy sources.
http://water.xprize.org/
Anonymous Because I'm Lazy
Where did they test this thing and what was the relative humidity during the test? 3 liters isn't enough for one person to survive on in the desert (1 gallon per person per day) so you'd really need a lot of them for normal daily use and a lot more to be able to grow crops.
Taking water away from a place where it's already scarce. It's not like the desert needs it, right?
I mean if drinking distilled water is bad for you, long term, without adding the minerals that your body needs, that's not really a good solution. Plus, I expect this water is going to be pretty hot since it's sitting in the desert sun, so that the solar panels can power it, so... Maybe the real application for this is that they have a really fancy way to boil a pot of water to cook their noodles? I didn't really think that my 10 cent pack of ramen needed a more cost effective cooking mechanism, but if they put it on Kickstarter, I'm totally buying one because that obviously means that I need it. /sarcasm
Dissenter
"There is no knowledge that is not power."
"Israeli firm to provide drinking water — from the air — for India and VietnamDeal to benefit remote Indian villages, Hanoi residents, announced days after Alan Dershowitz showcased Water Gen device at AIPAC"
http://www.timesofisrael.com/israeli-firm-to-provide-drinking-water-from-the-air-for-india-and-vietnam/
https://www.youtube.com/watch?...
has typed the words "moisture vaporators" prior to this?
Damn, has this place gone downhill.
Know wa'am say'n?
New Solar-Powered Device Can Pull Water Straight From the Desert Air
Yeah, it's called a sheet of plastic.
"There is more worth loving than we have strength to love." - Brian Jay Stanley
Second-world community I knew had a condenser for night dew installed by a global charity. Two nights later, the locals had stolen the polythene sheeting on which it relied. 'Appropriate Technology' Rules OK.
I was at an Earth Day festival in Santa Barbara CA, year before last. I don't remember the pricing for the appliances, but the one that I remember was $1000 new ($800 or 900 for a demo model) and it would do 16 litres of water per day, depending on humidity and tempurature. It was the height of a typical water cooler. While I thought the pricing was somewhat high, I figure that in places where water can sometimes run out (certain places and certain times of the year in South Asia), it's nice to have some insurance. Nevertheless, this is hardly news.
if implemented widescale, it will screw up weather patterns globally. there's a finite amount of water on the earth.
Remember kids, if you're not paying for the service, YOU ARE THE PRODUCT THAT IS BEING SOLD.
I've been using one of these on Arrakis for years..
But . . . people fart in it.
"I believe in Karma. That means I can do bad things to people all day long and I assume they deserve it." : Dogbert
It's a solar-powered dehumidifier. Yipee.
http://www.sciencemag.org/news...
It should be 30 deciliters. C'mon, get the units right. It's a windtrap.
--Shai-Hulud
What powers the cooling of the condenser? It takes a lot of juice to condense water out of air.
the obvious place 2 start is by asking the question: "isn't this going to affect the climate if we build enough of these things?"
If the answer is yes, does that mean these devices are a republican conspiracy to destroy mother nature.if the answer is no does this not mean this is a democratic conspiracy to keep promote abortions and gun control.
These questions seem obvious to me and I expect the crack journalist on CNN, Fox and Slashdot to begin debating this shit
Why? The solar "manufacturers" aren't. They're assemblers. They exist to extract government subsidies and have no long-term plans. Bankruptcy will take care of the warranties for them.
Yeah, imagine how much kg of copper one would need for 1 acre of, let's say, corn.
"Trump!!", the new Godwin.
1. copy paste some old news
2. post it
3. profit