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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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  • by John Hasler ( 414242 ) on Sunday November 23, 2008 @03:20PM (#25866281) Homepage

    ...the dehumidifier!

    • Exactly my first thought on reading this, too.

    • by goatpunch ( 668594 ) on Sunday November 23, 2008 @03:30PM (#25866385)

      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]

    • by geekmux ( 1040042 ) on Sunday November 23, 2008 @03:37PM (#25866457)

      ...the dehumidifier!

      Don't be a smartass. It's a dehumdifier with a filter. Big difference.

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

          Yeah, but that only works at night

        • by Macman408 ( 1308925 ) on Sunday November 23, 2008 @05:15PM (#25867275)

          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...).

          • 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.

            • Re: (Score:3, Informative)

              by Anonymous Coward

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

          • 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 badboy_tw2002 ( 524611 ) on Sunday November 23, 2008 @06:38PM (#25867861)

            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!

          • by Anonymous Coward on Sunday November 23, 2008 @07:28PM (#25868185)

            Or perhaps your machine wasn't puting out the UV light like it should have, Hell, someone probably looked at the 20 dollar bulbs and said this $1.57 one looks like the same thing.

            We did similar experiements in 8th grade, we subjected a lot of things to uv light and it always killed them. I even know of sewage treatment systems that use UV light in the last stage and have never found anything growing in the samples. I'm pretty sure it had something to do with your UV source.

          • Re: (Score:3, Informative)

            by Reziac ( 43301 ) *

            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 LordKaT ( 619540 )

      Hm ... funny or insightful, insightful or funny ...

      Oh fuck I just commented, nevermind.

    • by vlm ( 69642 ) on Sunday November 23, 2008 @04:52PM (#25867137)

      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.

      • Re: (Score:3, Interesting)

        by KDR_11k ( 778916 )

        The output might depend on the climate it's in, would your dehumidifier grab as much water in the desert?

        The "dry air" simply has a lower water saturation, hot air can hold more water than cold air.

      • Re: (Score:3, Interesting)

        by mpe ( 36238 )
        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.

        In practice it could mean anything between
        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.

        Thus you'd need several of these mach
        • by narcberry ( 1328009 ) on Sunday November 23, 2008 @08:40PM (#25868667) Journal

          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.

      • Re: (Score:3, Insightful)

        by RealGene ( 1025017 )
        The Guardian article dropped a decimal place. According to the manufacturer's press release [elementfour.com], it costs $0.03 (3 cents) per liter, or $0.35 (35 cents) per day.

        The latent heat that must be removed when water vapor condenses to liquid is 540 calories per gram.
        At a room/air temperature of 20 degrees C, 12 liters of water is 11,978 grams.
        So, to condense that 12 liters of water would take 6,468,336 calories, or 27,063,518 joules,
        which is equivalent to 7.52 kilowatt hours.

        Now, a well made, typical Peltier
      • by mcgrew ( 92797 ) * on Monday November 24, 2008 @09:53AM (#25872095) Homepage Journal

        "Three light bulbs" is journalistic code for 300 watts.

        I was going to be snarky but I got to the party late. Screw it, I'll get snarky anyway (not to you; your comment makes it a bit more on-topic). I have CFLs, so this thing uses 75 watts? Or maybe the morons are talking about 600 watt street lamps, so it's 1800 watts?

        This is slashdot. We know what a watt is. Saying "the power of three lightbulbs" at a nerd site is not only fucktardedly stupid, but insulting as well.

        Someone mod the submitter down, "-1 not a nerd and stupid besides."

  • by eln ( 21727 ) on Sunday November 23, 2008 @03:21PM (#25866301)

    They would get much better results using one of these things in thick, humid air rather than insisting on using thin air.

  • by mark0 ( 750639 ) on Sunday November 23, 2008 @03:23PM (#25866313)
    ... but won't spend the money on first class stamp to write to their public water authority and complain about whatever it is they think is wrong with the water supply?
    • by c ( 8461 ) <beauregardcp@gmail.com> on Sunday November 23, 2008 @04:15PM (#25866841)

      "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.


  • Dune (Score:5, Interesting)

    by rufus t firefly ( 35399 ) on Sunday November 23, 2008 @03:24PM (#25866323) Homepage

    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.

  • Didn't he make a living with these machines back in the 70's? Something about moisture vaporators...

  • by karstux ( 681641 ) on Sunday November 23, 2008 @03:25PM (#25866333) Homepage

    I'm somewhat sure that a communal water treatment plant achieves a better efficiency than 600 watt-hours per litre.

  • by Keychain ( 1249466 ) on Sunday November 23, 2008 @03:25PM (#25866335)
    That's what it is, just vaporware !
  • Uhh... am I missing something, or is it just a dehumidifer with a UV light (and maybe some antimicrobial plastic)? Here's a hint: if you are so desperate for water as to need this, there's probably very little moisture in the air anyway.

    The target market for this is the ecologically-posturing super-yuppie who doesn't like bottled water but wouldn't be caught dead using (horrors!) water from the plebeian tap.

  • by TheSpoom ( 715771 ) * <slashdot@@@uberm00...net> on Sunday November 23, 2008 @03:28PM (#25866375) Homepage Journal

    If we can solve the problem of giving it power (possibly with a hand crank and battery or some such thing), this should be sent to countries where drought is a problem.

  • by powerslave12r ( 1389937 ) on Sunday November 23, 2008 @03:28PM (#25866377)
    If these go wide-scale, wouldn't our air be drier? Which in turn would allow more water to be sucked up in the air from the nearby water bodies, which basically means you're getting your water through the air, or wireless (sic) if you will.
    • by Dutch Gun ( 899105 ) on Sunday November 23, 2008 @03:37PM (#25866453)

      getting your water through the air, or wireless (sic) if you will

      How about "tubeless"?

    • you just described the water cycle.

      We pull it from somewhere. might as well be the air.

      • by fm6 ( 162816 ) on Sunday November 23, 2008 @05:32PM (#25867399) Homepage Journal

        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.

  • Hmm. (Score:5, Funny)

    by fuzzyfuzzyfungus ( 1223518 ) on Sunday November 23, 2008 @03:31PM (#25866393) Journal
    How long will we have to wait before Linux has support for the binary language of moisture vaporators?
  • Minerals? (Score:2, Insightful)

    Regular tap water has a small amount of minerals, whereas distilled water (which this is, I presume) has none. Those minerals are actually rather critical:

    http://en.wikipedia.org/wiki/Water_intoxication [wikipedia.org]

    (Of course, regular tap water is dangerous too in laaarge doses.)

    I have no idea if this is an issue... Anyone have a clue? :)

    Also, three lightbulbs? Watts please... Found no proper specs on the site.

    • Might want to check your post, it's a bit disjointed.

      The minerals in tap water are indeed useful, if not critical. Most distilled water intended for drinking has 'minerals and salts added for taste'. ;)

      As your post notes, water intoxication is indeed a valid issue - on average it takes out a couple of military people in basic training a year.

    • Re: (Score:3, Funny)

      Of course, regular tap water is dangerous too in laaarge doses.

      In very large doses, everything eventually collapses and forms a black hole, and black holes, as we all know, are dangerous. Therefore, everything is dangerous in large doses.

      • Re: (Score:3, Insightful)

        by Alterion ( 925335 )
        more to the point, in large doses water has the unenviable effect of drowning you..
    • Re: (Score:3, Informative)

      by v1 ( 525388 )

      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

  • by Anonymous Coward on Sunday November 23, 2008 @03:35PM (#25866441)

    Nowadays, you either bring all your water along in tanks or use vaps to get fresh water from seawater.

    If this works reliably and with that small amount of power, I can see ships and submarines adopting this to save weight and power requirements.

  • Why? (Score:3, Insightful)

    by hcdejong ( 561314 ) <hobbes@[ ]net.nl ['xms' in gap]> on Sunday November 23, 2008 @03:40PM (#25866489)

    The Element Four site doesn't say, but the inane "3 lightbulbs" remark from the Guardian article suggests it uses 200-300 W to produce 12 liters of water per day, if the humidity is >30%. Assuming 200 W, that's 1750 kWh/year.
    The site markets this to First World households. But is that where its value lies? I get potable water from the tap, and so does most of Europe (and I pay E 1/m^3 instead of $0,30/litre). IDK about the States. The site mentions a ludicrous amount of bottled water, is that because US tap water isn't potable or is it just a fad?

    The locations that most need this (hot and dry climates) I guess would fail the "humidity >30%" criterium.

    The site only compares its efficiency with that of "bottled water" production, but what we need would be a comparison with e.g. a desalinisation plant.

    Sorry for rambling a bit, but it adds up to this: is this condensor something the world needs, or just another "a fool and his money are soon parted" scheme?

  • by overshoot ( 39700 ) on Sunday November 23, 2008 @03:40PM (#25866493)
    Perfect for people who have lots of money and electricity but no water service.

    Both of them.

  • Snake Oil (Score:5, Insightful)

    by Conspicuous Coward ( 938979 ) on Sunday November 23, 2008 @04:17PM (#25866871)

    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.

  • by noidentity ( 188756 ) on Sunday November 23, 2008 @04:45PM (#25867091)
    I hate it when summaries/articles give incomplete information, like this:

    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 [...]"

    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.

  • 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]

"This is lemma 1.1. We start a new chapter so the numbers all go back to one." -- Prof. Seager, C&O 351