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Earth Science Technology

Machine Condenses Drinking Water Out of Thin Air 438

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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Machine Condenses Drinking Water Out of Thin Air

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  • Re:Just Vaporware (Score:4, Informative)

    by K. S. Kyosuke ( 729550 ) on Sunday November 23, 2008 @03:33PM (#25866425)
    Exactly the opposite, this machine turns vaporware into a solid liquid product.
  • by Firethorn ( 177587 ) on Sunday November 23, 2008 @03:40PM (#25866495) Homepage Journal

    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.

  • by v1 ( 525388 ) on Sunday November 23, 2008 @03:46PM (#25866563) Homepage Journal

    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.

  • Re:Minerals? (Score:3, Informative)

    by v1 ( 525388 ) on Sunday November 23, 2008 @03:53PM (#25866641) Homepage Journal

    Here in Iowa we get our water from limestone-based aquafers and sand wells. Water's almost crunchy. I just got done using an entire gallon of vinegar to remove the lime from my bathtub, and I have to soak the tap filters several times a year or the screens solidify.

    Though once you get used to drinking "real water", bottled water is almost nasty tasting. It's hard to describe... it's just like drinking water from a tap at someone's house that has a water conditioner. It almost has a soapy or dulling/flat taste to it. There's just something a whole lot more refreshing drinking ice cold water that has some mineral content to it.

    I don't like drinking the water when I travel. Water that's either bottled, conditioned, or reclaimed out of the local river and gone through intense filtering. I need to start packing my own water when I go on vacation...

  • by repvik ( 96666 ) on Sunday November 23, 2008 @03:59PM (#25866693)

    Yeah, but that only works at night

  • Re:Useful on boats? (Score:3, Informative)

    by profplump ( 309017 ) <zach-slashjunk@kotlarek.com> on Sunday November 23, 2008 @04:03PM (#25866737)

    At 300 watts you'd need a fair amount of solar panels. And even then you'd only be able to run it during the day -- if you wanted to run it 24/7 you'd need something more like 1+ kW and a battery system. And you'd still be hoping for enough rain to drink rainwater any day it wasn't sunny.

  • Re:dehumidifier? (Score:2, Informative)

    by WTF Chuck ( 1369665 ) on Sunday November 23, 2008 @04:27PM (#25866935) Journal

    I think that a large life raft would be better equipped with something more like this [binnacle.com].

  • Re:Minerals? (Score:0, Informative)

    by Anonymous Coward on Sunday November 23, 2008 @04:30PM (#25866957)

    Your post is 100% BULLSHIT.

    Minerals from water have a negligible contribution to diet. They are measured in parts per million - and there's basically nothing there that the body can work with.

    Any argument to the contrary is complete shit.

    Contaminants are a different story (lead / arsenic, etc) - but they still won't kill you instantly. Otherwise it would be rather easy to detect water problems when consumers die overnight.

  • by moortak ( 1273582 ) on Sunday November 23, 2008 @04:33PM (#25866977)
    The Great Lakes are already out as an option. The Great lakes water pact passed.
  • Re:dehumidifier? (Score:3, Informative)

    by AmIAnAi ( 975049 ) * on Sunday November 23, 2008 @04:38PM (#25867015)
    Life rafts are already supplied with a Solar Still [mailspeedmarine.com] for converting saline water to fresh - and they are solar powered.
  • Re:Minerals? (Score:1, Informative)

    by Anonymous Coward on Sunday November 23, 2008 @05:24PM (#25867335)

    I don't like drinking the water when I travel. Water that's either bottled, conditioned, or reclaimed out of the local river and gone through intense filtering. I need to start packing my own water when I go on vacation...

    What you really should avoid is drinking *tap* water when you travel. In a lot of places local people can drink the water just fine because their immune system is used to it, while if you'd drink it, it could really spoil your vacation ;)

    All the rest is just a luxury problem.

  • by Chabil Ha' ( 875116 ) on Sunday November 23, 2008 @05:29PM (#25867375)

    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.

  • by calidoscope ( 312571 ) on Sunday November 23, 2008 @05:38PM (#25867439)
    The theoretical limit for reverse osmosis from sea water is something like 830 watt-hours per cubic meter. Commercially available systems are close to 2,000 watt-hours per cubic meter or 2 watt-hours per liter.

    IOW, your comment is an understatement.

  • by flyingrobots ( 704155 ) on Sunday November 23, 2008 @05:38PM (#25867441)

    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

  • by Anonymous Coward on Sunday November 23, 2008 @05:40PM (#25867467)

    Most water regulations in the US require 4 nines deactivation of specific indicator viruses and 3 nines removal of specific indicator bacteria.

  • Re:Useful on boats? (Score:4, Informative)

    by vlm ( 69642 ) on Sunday November 23, 2008 @05:51PM (#25867551)

    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.

  • by Fulcrum of Evil ( 560260 ) on Sunday November 23, 2008 @05:57PM (#25867593)
    No, Frank Herbert came up with the idea 50 years ago - read Dune for some real education.
  • by chill ( 34294 ) on Sunday November 23, 2008 @06:24PM (#25867773) Journal

    Sir, I do think you just uncovered the long lost answer to:

    2. ?
    3. Profit!

    Hell, it seems to have worked for Lucas.

  • by tigerhawkvok ( 1010669 ) on Sunday November 23, 2008 @06:26PM (#25867791) Homepage
    Something is wrong in that calculation ... the second link goes to the product's home page, which states:

    "The original WaterMill is designed for the residential user. It provides families with a clean, sustainable and cost-effective source of water for drinking and cooking. It produces 12 litres (13 US quarts) of water per day, and mounts to the exterior of your home, drawing water from the air outside into point-of-use systems inside. The WaterMill is self-regulating, maximizing water production, while minimizing energy consumption."
    [source] [elementfour.com]

    So ... the best I can figure is that it might actually be referring to the CFLs. If a 60W equivalent CFL draws something like 10W (somewhere between 7 and 15, I don't recall), this (roughly) factor of six will take your two liter estimate up to twelve liters, or in line with the product page.

    The most surprising thing about this is that it would mean journalists are changing their light-bulb benchmarks!
  • by Beavertank ( 1178717 ) on Sunday November 23, 2008 @06:32PM (#25867823)
    The problem with that is in order to be killed by the UV light (and it doesn't actually kill the bacteria, just scrambles their DNA so badly that they can't successfully reproduce) the bacteria has to be exposed to it.

    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.
  • by lethargic8 ( 1179029 ) on Sunday November 23, 2008 @06:35PM (#25867843)
    While you are right that that a humid environment means there is probably water, but that does not mean there is drinkable water. There is a crapload of water in the developing world that simply is not healthy to drink. It is why diarrhea is one of the biggest killers in many developing nations.
  • by daBass ( 56811 ) on Sunday November 23, 2008 @07:39PM (#25868249)

    That's probably mostly the case in the US, with Coke's Dasani crap owning market. I once bought a bottle as soon as I arrived at the airport. That stuff tasted foul. On closer inspection of the bottle I found the words: "purified water". Not very well purified it seems.

    In Europe and Australia at least the vast majority is from natural springs. In fact, when Coke tried to bring Dasani to the UK, they were laughed out of the country [commondreams.org].

    You can buy bottled, purified, tap water in UK supermarkets, but that is always clearly labeled "table water" and a fraction of the cost of spring water. Dasani, on the other hand, cost as much as Evian!

    Weather I drink the tap water or not mainly depends on taste. The water in the Netherlands and Germany is absolutely fine and Evian doesn't taste any better. Same with Scandinavia and Iceland. (they have spring water from the tap it seems!)

    The UK is absolutely putrid - tastes like raw sewage. Australia and the US are over chlorinated - like drinking a swimming pool.

    I have a special filtered tap next to my normal one here in Australia. This is what I use for drinking and cooking. More expensive to install, but more convenient than a table-top filter and cheaper in the long run because of lower filter costs.

  • by mr100percent ( 57156 ) on Sunday November 23, 2008 @08:18PM (#25868505) Homepage Journal

    Legionnaires' disease is only if you INHALE the bacteria. The germ is ubiquitous in water, and drinking it is harmless.

    Wiki Legionella [wikipedia.org]

  • by dunkelfalke ( 91624 ) on Sunday November 23, 2008 @08:34PM (#25868607)

    standard tabletop filters don't filter that much - the filter inside it has got a bit of charcoal to absorb some chemicals, a bit of silver to hinder the biofilm growing inside for a couple of weeks and an ion exchanger like zeolite to replace the calcium in water for sodium.

    if you really are paranoid about tap water, try reverse osmosis. but then you'll have the same problem as with distilled water - it lacks potentially needed minerals and might even wash minerals out of your body. then again, good tea tastes much better with purified water.

  • Coke's UK launch of Dasani failed primarily due to an almost immediate full recall [bbc.co.uk] after the initial batches were found to be contaminated with bromate. That basically killed the brand from the start, making what people thought of tap vs. spring water a moot point.

    (And the bromate contamination was, oddly enough, not actually present in the tap water they source Dasani from, but was introduced in the "purification" process.)

  • by JSBiff ( 87824 ) on Sunday November 23, 2008 @09:41PM (#25869047) Journal

    I don't think this is much of an issue to worry about because:

    1) This tech is only really useful in areas where there isn't already abundant fresh water. For example, I live in Ohio, USA. We have lots of rivers (including the Ohio River, which is a large tributary river of the Mississippi R.), streams, lakes (including a northern coast on Lake Erie, one of the "Great Lakes", which contains a pretty massive amount of fresh water), and lots of ground water as well. Because of the energy requirements to operate this thing, I suspect that treated water from a municipal water network is probably much cheaper in much of the world.

    2) I don't think that 6, or even 10 billion humans could out-use the water evaporated from the oceans, rivers, and lakes by the Sun, although I suppose that, *maybe* we could inadvertently change weather patterns a little bit. This point, however, I will admit, is pure speculation on my part and I don't have any hard data to back it up. Just a knowledge that a massive amount of solar energy hits the earth's surface every day, and that some 80% of the earth is covered by water, so, basically, about 80% of the energy from the Sun goes to evaporating water (ok, some percentage of the energy is reflected off the surface of the water, so that statement's not, probably, quite true, but gives us a good starting point for thinking about the problem).

  • by jeepien ( 848819 ) on Sunday November 23, 2008 @09:47PM (#25869085)
    Sorry, but you're flat wrong. You say "in fact" but you've never measured it.

    You see, at a given temperature and pressure, there are a given number of gas molecules per unit volume. That's counting nitrogen, oxygen, water vapor, everything.

    Nk = PV/T

    But never mind theory. The fact is, humid air is substantially less dense than dry air in real life. (There's a lot of truth in what actually happens.) The measurement confirms the theory nicely. For further proof, planes need more runway (higher speed) to take off in high high humidity, other factors being equal. Go ask a pilot, a high-school physics or chem teacher, or a bright student.
  • by Sanat ( 702 ) on Sunday November 23, 2008 @10:07PM (#25869199)

    The whole Yavapai County area.

    I lived in Sedona and spent time in Cottonwood. Both of these places as well as the Prescott Valley area has varying degree of arsenic in the ground water.

    Of course, the wells are very deep typically 200 feet or more. Back in the Midwest one can dig a hole in the ground with a shovel and have it fill up with water.

    Typical well water in Cottonwood Arizona area contains approximately 50 ppb

    The University of Arizona
    Cooperative Extension
    Recommends:

      Test your well water regularly....including Arsenic

      Determine the level of Arsenic contamination and what is your exposure level to Arsenic.

      If you are experiencing any health problems which could be caused by excessive exposure to Arsenic.... consult your family physician or Arizona Department of Health Services.

      If your well water Arsenic tests exceed 10ppb, stop drinking it...move to a safer source of water for drinking and cooking while you come up with a plan.

  • by westlake ( 615356 ) on Monday November 24, 2008 @12:33AM (#25869941)
    I don't know if there are any good kits for steam distillation at home, can anyone point me to one?

    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.

  • by iocat ( 572367 ) on Monday November 24, 2008 @12:52AM (#25870021) Homepage Journal
    The water created by a dehumidifier is prolly much cleaner than the water sources in some third-world areas. I remember early (and sucessful) attempts to reduce disease by having people in some parts of India and (what is now) Bangledesh simply filter their water through multiple layers of cheese cloth before they drank it.
  • MOD UP (Score:4, Informative)

    by bagsc ( 254194 ) on Monday November 24, 2008 @02:24AM (#25870451) Journal

    http://www.elementfour.com/products/the-watermill [elementfour.com]

    "The WaterMill is designed to minimize energy use. It's so efficient that producing one liter of water costs only three to four cents. Alternative bottled water systems typically cost ten cents per liter or more."

  • by Reziac ( 43301 ) * on Monday November 24, 2008 @03:17AM (#25870623) Homepage Journal

    If UV sterilized everything, you'd think the Great Outdoors would be microbe-free, and that's hardly the case (nor would we like living here much if it were! :)

    I'm reminded of an experiment we did in some advanced college microbiology course. First we grew bacteria from random realworld samples, then assaulted it with various antibiotics to kill it off. Well, that much worked, but all sorts of other interesting slime then grew on the agar instead. :)

  • by borizz ( 1023175 ) on Monday November 24, 2008 @07:37AM (#25871449)
    Reverse osmosis handpump to desalinate seawater. Should be in most liferafts. Costs about 100 dollars in any outdoor store, about as large as a paperback.
  • by LeadSongDog ( 1120683 ) on Monday November 24, 2008 @12:13PM (#25873593)
    How much more power does a 100W bulb draw if it's inefficient?

    Personally, I think they should check out Fog Catchers http://ngm.nationalgeographic.com/ngm/0308/feature3/ [nationalgeographic.com] like the ones used in the Atacama Desert. Of course, they do have the requisite mountain range.http://archive.idrc.ca/nayudamma/fogcatc_72e.html [archive.idrc.ca]
  • by smellsofbikes ( 890263 ) on Monday November 24, 2008 @12:31PM (#25873819) Journal

    He did [wikipedia.org]. From a Kurosawa film from the '50's. Including the behavior (although not the appearance) of R2D2 and C3P0.

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