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Machine Condenses Drinking Water Out of Thin Air
Posted by
timothy
on Sun Nov 23, 2008 02:18 PM
from the LED-bulbs-or-klieg-light-specials? dept.
from the LED-bulbs-or-klieg-light-specials? dept.
longacre writes "A new $1,200 machine that uses the same amount of power as three light bulbs promises to condense drinkable water out of the air. On display at Wired Magazine's annual tech showcase, the WaterMill 'looks like a giant golf ball that has been chopped in half: it is about 3ft in diameter, made of white plastic, and is attached to the wall. It works by drawing air through filters to remove dust and particles, then cooling it to just below the temperature at which dew forms. The condensed water is passed through a self-sterilising chamber that uses microbe-busting UV light to eradicate any possibility of Legionnaires' disease or other infections. Finally, it is filtered and passed through a pipe to the owner's fridge or kitchen tap.'"
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Amazing! They've invented... (Score:5, Funny)
...the dehumidifier!
Re:Amazing! They've invented... (Score:5, Funny)
No, it's called a Vaporator, and it was invented by George Lucas in the 70's: http://upload.wikimedia.org/wikipedia/en/8/83/Luke-Treadwell_close_large.jpg [wikimedia.org]
Parent
Re:Amazing! They've invented... (Score:5, Funny)
Now all we need is a droid that understands the binary language of moisture vaporators.
Parent
Re:Amazing! They've invented... (Score:4, Funny)
You mean George Lucas stole it from the designs of the Fremen windtraps in Dune, just like he stole everything else in Star Wars.
Parent
Re:Amazing! They've invented... (Score:5, Funny)
Yes, but to compensate he added muppets.
Parent
Re:Amazing! They've invented... (Score:5, Informative)
Sir, I do think you just uncovered the long lost answer to:
2. ?
3. Profit!
Hell, it seems to have worked for Lucas.
Parent
Re:Amazing! They've invented... (Score:4, Informative)
Parent
Re:Amazing! They've invented... (Score:5, Funny)
...the dehumidifier!
Don't be a smartass. It's a dehumdifier with a filter. Big difference.
Parent
Re:Amazing! They've invented... (Score:5, Informative)
Don't forget the sanitizing UV light...
I remember instructions on how to make something like this in the scouts - it involved a sheet of plastic and some rocks.
Parent
Re:Amazing! They've invented... (Score:4, Informative)
Yeah, but that only works at night
Parent
Re:Amazing! They've invented... (Score:5, Funny)
Parent
Re:Amazing! They've invented... (Score:4, Interesting)
Don't forget the sanitizing UV light...
You know, I've never been terribly confident in those since an 8th grade science experiment. I think the point was to try and come up with something that might cause a mutation in some bacteria - so we grew some in a petri dish, picked one colony (to get all the same type of bacteria), then grew it in a petri dish, then picked some out of that uniform batch and put them in another petri dish. We covered half with aluminum foil, then put it in the UV hood designed for disinfecting lab goggles. The bacteria had no problems growing after being supposedly "killed" by the UV (not to mention, no mutations like we wanted).
Of course, that was still an interesting result that our science teacher liked - so we spread more bacteria on a petri dish, put it uncovered into the UV hood (in case the plastic on the petri dish was opaque to UV or something like that), and ran it for much longer than normal. The bacteria still had no problems growing.
Now maybe it's just difficult to kill bacteria when you've put them on top of a nice big pile of food (aka agar)... But I really don't expect UV to kill anything. That doesn't mean I wouldn't drink the water - it just means that the UV shouldn't be the only line of defense if I think there's really a risk of getting sick (which there probably isn't a big one anyway...).
Parent
Re:Amazing! They've invented... (Score:5, Informative)
I think the point is not to sterilize the water, but make it safe to drink. Our bodies are fairly tolerant to bacteria getting inside. Think of it this way: Do you really think that tap water is 100% germ free? Is the glass you're putting your lips on sterile?
The idea of the UV light is to get the parts/qty down to such a level as to be safe for your body to take care of the rest.
Parent
Re:Amazing! They've invented... (Score:5, Informative)
I'm assuming you got some nice fuzzy mounds in pretty colors, all very opaque. Exposing those mounds to UV light mutates the surface bacteria so badly that they can't reproduce, but you've still got millions upon millions living beneath that one layer in ignorant bliss because their brethren above them absorbed all the UV radiation, sparing them.
The reason UV exposure works better in water is because water is clear and any bacteria that is present is not masked by... well... anything. It even works in fairly turbid water, assuming the water is agitated while being exposed to the UV so all areas get equally exposed.
Sorry to poke holes in your 8th grade fun... but that's what you were observing, not the failure of UV light to kill things.
Parent
Re:Amazing! They've invented... (Score:5, Funny)
Damn, that was you? I remember reading that article in 8th Grade Science Weekly. Mindblowing dude, mindblowing. If I recall correctly, it was right next to an article about a new field of geological theory based on the observation of baking soda volcanoes. That reminds me, better go renew my subscription!
Parent
Re:Amazing! They've invented... (Score:5, Funny)
WHO?
Parent
Re:Amazing! They've invented... (Score:5, Insightful)
My dehumidifier in my basement also uses "the electricity of about three light bulbs". The article claimed "$0.3 per litre". Lets run the numbers.
"Three light bulbs" is journalistic code for 300 watts. My electricity costs about 8 cents per kWh. $0.3 per liter implies it uses 3.75 kWh per liter. At 300 watts, it takes 12.5 hours to generate a liter of water. Or rephrased, it could fill a 2 liter soda bottle in about a day.
However, my $200 Chinese dehumidifier purchased at home depot, using the same electricity, easily fills its multigallon bucket in a day, at least during summer months. To help any NASA scientists here, multiple gallons is quite a bit more than two liters.
So, why does this greenwashing gadget cost five times as much as my dehumidifier but only produces about half the output? Surely it can't be continuously dumping 150 watts of UV sterilization light. Maybe those are metric kilowatt-hours as opposed to imperial kilowatt-hours.
The last line is also funny "reduces it from mid-afternoon when a blazing sun dries the air." The only way to dry air is rain, snow, mixing with drier air, dew, and frost. I am a firm believer in the conservation of mass, In a closed system if you evaporate a gallon at midnight I think it will still be there at noon. So, where, pray tell, does the water in the air go when the sun strikes it? Into a cave like a vampire? Outer space? Surely the "blazing sun" isn't visible from underneath a thunderstorm. I think in their inept little journalist way they are trying to say the device becomes vastly less efficient as the relative humidity falls. That would be no big deal, except that where ever there is high humidity, there is probably open water, and its usually cheaper to filter and desalinate open water than to dehumidify it. There is a certain perfection in a device that only works where you don't need it and can't work where you would otherwise need it the most.
Parent
Re:Amazing! They've invented... (Score:5, Funny)
Or where our water supply is hijacked by a multinational illuminati-esque superpower spending multiple billions of dollars drilling and building super secret underground dams restricting the flow of ground water in a coordinated attempt with the CIA and other world powers to make millions by raising the price of water, which still rains in large quantities.
Also, did you know water vapor is the biggest contributor to the greenhouse effect? This should help stop that.
Parent
Re:I bought one last week for $135. (Score:5, Insightful)
I don't know if there are any good kits for steam distillation at home, can anyone point me to one?
Parent
Home Distallation Kits (Score:5, Informative)
Steam Distiller for Countertop [promolife.com] $180. 565 watts. 1 gallon every 4 hours. You say you want 20 gallons a day? That will cost you $5000 and draw down 3000 watts 24/7/365. Polar Bear Home Water Distiller [betterthannature.com] For the geek, the micro-brewery might be the better - or at least, more rewarding - investment.
Parent
Seems kind of silly (Score:5, Funny)
They would get much better results using one of these things in thick, humid air rather than insisting on using thin air.
Who spends $1200 for a pimped dehumidifier... (Score:5, Funny)
Re:Who spends $1200 for a pimped dehumidifier... (Score:5, Interesting)
"public water authority"?
Ah... you must live in a large built-up area where water comes out of a big pipe provided by a municipality of some sort.
I'm on a dug well with extremely hard water and a tendency to go dry during droughts. Between the filters, UV treatment, water softener, RO filter system, pumps, cisterns, etc... there's probably $5000 for all the bits and parts of my water system. I've spent $1200 on far dumber things than drinking water. For someone with, say, a sulphur problem... $1200 would be darn cheap.
c.
Parent
Re:Who spends $1200 for a pimped dehumidifier... (Score:5, Insightful)
> I imagine the target market is people who live off the grid...
Such people usually use a clever invention called a well.
> ...a backup in case the grid fails.
It comes with a hand crank?
Parent
Re:Who spends $1200 for a pimped dehumidifier... (Score:5, Interesting)
And in many places, digging a well in prohibited. At least Colorado and other parts of the US West. Water rights are a major problem here; Colorado state law doesn't even allow you to collect water which runs off your roof: http://www.hcn.org/issues/40.18/a-good-idea-2013-if-you-can-get-away-with-it [hcn.org]
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Dune (Score:5, Interesting)
I'm surprised no one has mentioned Dune or its wind traps yet.
Or that no one has mentioned another story on slashdot [slashdot.org] about extracting water from wind, even if the other one used a windmill to do so.
Re:Or Star Wars (Score:5, Funny)
I don't know - coming to slashdot and getting you're/your wrong... *sigh*
Parent
Just Vaporware (Score:5, Funny)
Re:Just Vaporware (Score:4, Informative)
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Re:Just Vaporware (Score:5, Funny)
Solid liquid, eh? Exactly what phases of matter do you have over there?
Parent
The balance may remain.. (Score:5, Interesting)
Re:The balance may remain.. (Score:4, Funny)
getting your water through the air, or wireless (sic) if you will
How about "tubeless"?
Parent
Not quite the water cycle (Score:5, Interesting)
You're correct, that's exactly how the water cycle works. But this gadget skips a couple of steps.
The water that's in the bottle on my desk started out as atmospheric moisture over Northern California. Then it precipitated out as snow or rain, ending up as ground water or in a reservoir. From there it was pumped into the local water system, and where I siphoned it into my bottle. Eventually I'll drink it, piss it into a toilet, whence it will find its way through the sewage system and out to sea. Then it will evaporate into the air and the whole cycle will start over again.
Right now, only a small part of the the rain and snow that falls on Northern California ends up in the various water systems we humans depend on. The rest is used by what's left of the natural ecology. One reason this ecology keeps shrinking is that humans keep sequestering more and more water for their own use. With gadgets like this one, we could potentially sequester every single drop before it has a chance to fall out of the sky.
That notion might seem far-fetched. And indeed, we'll probably never go that far in a relatively moist region like the one I live in. But consider an arid region like Arizona. There's relatively little atmospheric moisture there, but what there is sustains a thriving desert ecology. It also is home to human communities that are always struggling to find water [westernfarmpress.com]. It's not hard to imagine Arizonans building enough of this gadgets to grab virtually all the precipitation before it has a chance to fall. When that happens, the desert ecologies are, so to speak, toast.
Which is not to say that this technology is totally evil. I can think of many situations where it would be the most ecologically sound way to obtain water. You just have to remember that this is not an ecological free lunch.
Parent
Hmm. (Score:5, Funny)
This is great! (Score:5, Funny)
Both of them.
Snake Oil (Score:5, Insightful)
It really pisses me off that even supposedly "quality" newspapers like the Guardian just reprint some PR's press releases with marginal editing rather than doing even the most basic of reasarch or even, god forbid, any thinking.
TFA answers none of the pertinent questions about this device. But reading between the lines and doing a little thinking it's pretty easy to determine this device is going to be useless as anything but a gimmik.
Firstly, how much power does it use? "Three lightbulbs" says TFA, now as far as I'm aware the lightbulb is not a standard measurement for power consumption. But let's be generous and assume they're taling about standard 60-80W bulbs, that about 200W, give or take.
How much water does it produce? The article doesn't say, their website claims "up to" 12L per day, which I'd imagine is operating under optimium conditions (i.e hot air at close to 100% humidity). That's actually not a lot of water, and i'd imagine operating in any real conditions you could halve or quater that amount.
So adding up the numbers, that's 4.8kWh of electicty to produce about 6L of water. Or 800kwh/m^3. This is a ridiculously, hideously energy intensive way to make water, even desalination, which is seen as ecologically unfreindly, uses about 3kwh/m^3, or is about 250 times more efficient.
TFA also states this device is useless below 30% humidity, which removes the last reason one might consider using it, providing water where no other method is possible.
My point in all this is that doing about 2 minutes thinking, and exactly one google search, I have been able to determine that this thing is anything but ecologically friendly, and anything but economic. The journo writing this article for the Guardian, which for those of you who don't know it prides itself on being a "green" newspaper, couldn't even be bothered to do that and reprinted some PR's words wholesale, giving people the impression that what is in fact a toy for rich consumers who want to feel good about being "green" is some kind of ecological miracle device.
It should be a source of lasting shame to any newspaper to allow their editorial content to be used by some idiot for marketing purposes, sadly it's all too common and nobody even seems to notice the extent to which PR is taking over journalism.
Re:Snake Oil (Score:5, Insightful)
Another way to say it: the amount of energy required to produce 6L of water is about equal to half a liter of diesel. Burning half a liter of diesel would produce about 7L of water.
This device is even more ridiculous than propelling a sailing ship with a fan powered by a windmill...
Parent
Incomplete information (Score:5, Insightful)
OK, it uses the same amount of power as three light bulbs when it's operating, but how long does it take to generate a liter of water? Without this, the "three light bulbs" is meaningless.
Legionnaires' disease? (Score:5, Informative)
Legionnaires' disease is only if you INHALE the bacteria. The germ is ubiquitous in water, and drinking it is harmless.
Wiki Legionella [wikipedia.org]
Re:Send this to the third world (Score:5, Insightful)
At 600 watt-hours per liter, you're going to be losing more energy to sweat and breathing than you could possibly get close to generating by hand.
Parent
Re:Send this to the third world (Score:5, Insightful)
Yeah, this is ONLY 200 times less efficient than desalinization.
Criminy.
Parent
Re:Send this to the third world (Score:4, Interesting)
They are standard equipment on any "large" (50+ feet or so) Ocean going boat. They're pretty common even on 30-40 foot boats where the owners are planning extended off-shore voyaging.
Even more: http://www.katadyn.com/ [katadyn.com] manufactures hand powered reverse osmosis devices for lifeboat style use.
So yeah, Reverse Osmosis isn't limited to major industrial installations in any way.
Parent
Re:Send this to the third world (Score:5, Insightful)
this should be sent to countries where drought is a problem.
If drought is a problem I suspect there isn't going to be a whole lot of humid air to extract water from. "The mill ceases to be effective below about 30 per cent relative humidity levels,"
And after cranking that thing to produce 300W (about three light bulbs, and I'm guessing it means old-style, power inefficient, ones), you're going to need more than a glass of water.
And that's before we even consider the price tag.
Parent
Re:Send this to the third world (Score:5, Funny)
> And after cranking that thing to produce 300W (about three light bulbs, and I'm guessing
> it means old-style, power inefficient, ones), you're going to need more than a glass of
> water.
But you may sweat enough to drive the humidity up to 30% so that the thing will begin to work.
Parent
Re:Pretty sure this isn't new (Score:4, Informative)
not sure what the diff between this and that is, but this one says it's not useful below 30% rel humidity. Not useful in the desert. Not during the daytime anyway. Maybe at night. There's a lot of critters in the desert that get all of their moisture by licking up the morning dew.
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Re:Pretty sure this isn't new (Score:5, Informative)
Actually, it can get quite humid in the desret. I work with folks who have spent a lot of time in Saudi Arabia and in such places and they report that it is very humid in the summer time. The reason it doesn't rain is that there is no cold dry air masses that come down to mix with the hot humid ones.
There are some places this might be a very nice appliance.
Kevin
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Re:Uncle Owen? (Score:4, Funny)
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Re:Hmmmm. The arid west (Score:5, Funny)
Fixed that for you.
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Efficiency really sucks... (Score:5, Informative)
IOW, your comment is an understatement.
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Re:Useful on boats? (Score:4, Informative)
I know that getting drinking water is often an issue for smaller boats which may not have room or power for desalination or reverse osmosis units.
From a systems analysis standpoint, the dehumidifier machine doesn't work. It would be far more efficient to install an electric fan on the stern of the boat pointed at the sails, so as to go faster, thus requiring less stored drinking water. Err, maybe that wouldn't work, how about installing a big windmill in front of the sail and hooking that up to an electric trolling motor.
Seriously though, a Katdyn 35 hand operated R.O. desalinator pump produces about as much water in 30 minutes of hand pumping as this "dehumidifier" produces in a day of using 300 watts.
http://products.katadyn.com/brands-and-products/produkte/Survivor_34/Katadyn_Survivor_35_48.html [katadyn.com]
Or if you prefer to save your hand and arm strength for other purposes (?) and use electricity to desalinate, a katadyn model 40E/12V draws only 4 amps at 12 volts and squirts out 1.5 gallons per hour. It only weighs 25 lbs and is about 7 by 17 by 15 inches. It's amazing that the off the shelf katdyn produces about 30 times as much water per day yet uses about a tenth the electricity of this "greenwash" dehumidifier product.
http://products.katadyn.com/brands-and-products/produkte/Survivor_34/Katadyn_Survivor_35_48.html [katadyn.com]
I have no connection to katadyn other than happily owning a couple of their backpacking R.O. filters.
Parent