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Earth Science

DoE Considers Artificial Trees To Remove CO2 418

eldavojohn writes "CNN is running an article on a new angle of attack to reducing greenhouse gases. After meeting with the US Department of Energy on the concept, the researchers revealed the details that each 'tree' (really a small building structure in the concept design) would cost about as much as a Toyota and remove 1 ton of CO2 from the air per day. Don't worry, they're accounting for the energy the 'tree' uses to operate: 'By the time we make liquid C02 we have spent approximately 50 kilojoules [of electricity] per mole of C02. Compare that to the average power plant in the US, which produces one mole of C02 with every 230 kilojoules of electricity. In other words, if we simply plugged our device in to the power grid to satisfy its energy needs, for every roughly 1,000 kilograms [of carbon dioxide] we collected we would re-emit 200, so 800 we can chalk up as having been successful.' Each unit would remove 20 automobiles' worth of CO2 from the air and cost about as much as a Toyota... so the plan might be a five percent surcharge on automobiles to fund these synthetic tree farms."
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DoE Considers Artificial Trees To Remove CO2

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  • by swaha ( 101157 ) * on Tuesday June 23, 2009 @09:49AM (#28438903)

    Just like the fact that we legislated use of compact fluorescents with NO plan on disposal,
    we have a half thought out plan on liquifying CO2, but nothing on storage and disposal.

    • Re: (Score:3, Interesting)

      by LordKazan ( 558383 )

      Dry ice stays solid if you drop it down the bottom of as little as few hundred feet (maybe less) under ocean water.

      transport it all out to the Marianas Trench and drop it. not going to hypercarbonate the water because it'll stay solid below the right depth [which is reached rapidly if you put them on something that decreases hydrodynamic drag]

      • Keep it in a bio dome and let the real trees attempt to break it back to Oxygen :D
        • by Joce640k ( 829181 ) on Tuesday June 23, 2009 @10:53AM (#28439899) Homepage
          Can't we turn it into biodiesel with algae farms? That would be win-win.
          • Re: (Score:3, Informative)

            by LordKazan ( 558383 )

            interesting factoids that get my down modded by political hacks aside, that is actually a very good idea.

            if you close the carbon cycle by making all combustion fuels biofuels then then all the carbon our cars emit will have been first taken out of the atmosphere. this will allow natural carbon sinks to start removing the excess from the atmopshere and bring us back down to pre-industrial equilibrium.

            not saying we couldn't help speed up the process of removing the excess carbon.

          • by xaxa ( 988988 ) on Tuesday June 23, 2009 @11:18AM (#28440301)

            Can't we turn it into biodiesel with algae farms? That would be win-win.

            Or, build a glasshouse near your power plant. Pipe the CO2 from the power plant into the glasshouse. In winter (and summer, if needed) heat the glasshouse using waste hot water from the power plant. Grow tomatoes.

            This is already done in lots of places.

          • Re: (Score:3, Interesting)

            by geckipede ( 1261408 )
            It pains me to have to say this, but I think the people who propose dumping liquid co2 under pressure into old oil wells have the right idea. We don't have the capacity at the moment to deal with the massive amounts of co2 that these machine trees would crank out, not to do anything useful with it, and biofuel plants would take a hell of a lot of time to set up. Burying the gas has the downside of risking a massive poisonous cloud of doom if there's ever a leak, but at least once the leak disperses you're
      • by Anonymous Coward on Tuesday June 23, 2009 @10:10AM (#28439227)

        If CO2 COULD be a solid in the ocean, it WOULD be a solid in the ocean and there would be huge piles of the stuff down there.

        A few hundred feet down, the pressure is still less than 10 atmospheres and temp is obviously above 0ÂC (273K). CO2 under those conditions is still very much a gas. It won't stay solid at 0ÂC unless you're above about 5,000 atmospheres. Even at the bottom of Challenger Deep, you're barely 1100 atm.

        http://en.wikipedia.org/wiki/File:Carbon_dioxide_pressure-temperature_phase_diagram.svg

        • strange then how they demonstrated clearly that if you take DRY ICE [not gaseous CO2] and drop it to the bottom of a few hundred feet of water (in the Mediterranean no less.. this is warm water) it stopped sublimating.

        • Furthermore, the solubility of carbon dioxide in water increases as temperature decreases (for example, as you go down deeper into the ocean) and also increases as pressure increases (for example, as you go down deeper into the ocean) . There's no reason to think that CO2, if injected deep into the ocean, wouldn't dissolve into the water.

          I'm not sure what the impact of hypercarbonated deep oceans would be-- it would certainly take decades, and possibly centuries for the dense hyercarbonated water to diffu

          • by Noren ( 605012 ) on Tuesday June 23, 2009 @11:28AM (#28440451)
            I cannot imagine that it would take decades or centuries for dissolved CO2 to diffuse a few miles through water, even with a pressure gradient. I'd imagine months at most, more likely days.

            As an added disadvantage, the resulting carbonic acid would only speed up ocean acidification.
          • Re: (Score:3, Insightful)

            by geekoid ( 135745 )

            CO2 is currently making the oceans PH out of whack and killing corral reefs.

      • by alchemist68 ( 550641 ) on Tuesday June 23, 2009 @10:22AM (#28439413)
        As an experienced scientist, placing any form or CO2 in water is a very bad idea. Eventually it will change states from solid to gas or from solid to dissolved in water, which then is known as carbonic acid. This is exactly how your body deals with CO2, it is dissolved in your salty blood, where it is expelled as a gas from the lungs. Only hemoglobin transports oxygen to the tissues, it does not transport CO2 in any way shape or form. CO2 will influence the affinity oxygen has for hemoglobin, and in the presence of higher concentrations of carbonic acid, hemoglobin more readily releases oxygen to the surrounding tissues. Hemoglobin will also transport CO, carbon monoxide, but the binding is through carbon-metal (iron) back bonding, not through the oxygen. I didn't even mention the unknown effects this would have on marine life.

        The only way to curb CO2 in the atmosphere is to stop burning fuel and let natural vegetation grow. This also means letting forests GROW and not clear cutting for land development, wood, and paper.
        • They demonstrated that if you take dry ice and drop it under several hundred feet of ocean water it stops sublimating. they also loaded it onto an impactor that would drive it into the mud at the bottom.

          I don't disagree with your last sentence there, i was just pointing out something interesting about dry ice.

          • Re: (Score:3, Informative)

            by Andy Dodd ( 701 )

            It would stop sublimating into gas (fizzing and producing bubbles), but did they demonstrate that a year later the dry ice was still there?

            It might not be producing bubbles, but might slowly transition to dissolved gas in the water.

          • Re: (Score:3, Interesting)

            by sexconker ( 1179573 )

            It might stop sublimating at that pressure, but it still dissolves, and it does so slowly.

            A few decades from now the problem would be "OMG WE HAVE TO DIG UP ALL THE CHUNKS OF CO2 OR THE OCEAN WILL DIE!"

            The guy above you explained it very well.
            But how about a simpler example?

            Fish tank + CO2.

        • Only hemoglobin transports oxygen to the tissues, it does not transport CO2 in any way shape or form. CO2 will influence the affinity oxygen has for hemoglobin, and in the presence of higher concentrations of carbonic acid, hemoglobin more readily releases oxygen to the surrounding tissues.

          Not true. A hemoglobin can carry a single CO2 molecule (as opposed to the 4 molecules of O2 it can carry). However, since cellular respiration has a 1:1 ratio of O2 and CO2, the other 75% of the CO2 is carried as carbonic acid / bicarbonate. Anyway, the bonding of protons and a CO2 to hemoglobin decrease its affinity for O2, causing it to release the O2 in the capillaries near body cells where the pH will be lower due to the constant production of CO2 from respiration. A.K.A. the Bohr Effect. [wikipedia.org]

          • Re: (Score:3, Interesting)

            by alchemist68 ( 550641 )
            Sorry I wasn't more specific, hemoglobin will not transport CO2 by binding to the iron in the heme macrocycle (http://en.wikipedia.org/wiki/Heme) (http://en.wikipedia.org/wiki/Macrocycle). I did my graduate work in metallated porphyrin chemistry (http://en.wikipedia.org/wiki/Porphyrin). And thank you for pointing out the Bohr effect. I didn't expect the discussion to get 'this' technical, but it was nice to see the interest.
        • Re: (Score:3, Insightful)

          "not clear cutting for land development, wood, and paper."
          You're as much a "scientist" as I am a concert pianist! More likely you've proclaimed yourself such to add false authority to your post.

          "clear cutting" for land development is a requirement of land development. First you remove the vegetation, then you move the dirt into the shape you want, then you build whatever, then you plant on the remaining soil. This is why roads are straight.

          Geez, THERE'S an idea! New plants can be grown! Didn't think about t

      • by sunking2 ( 521698 ) on Tuesday June 23, 2009 @10:33AM (#28439639)
        Oh sure, until you wake up Megatron. Nice going.
      • Re: (Score:3, Informative)

        by sexconker ( 1179573 )

        It doesn't sublimate at the increased pressure.
        It DOES dissolve into the liquid, and it DOES become a gas.

        It does it slowly, and yes, it does so even when buried.

        (Reposting this here to make sure people see it.)

    • Re: (Score:2, Interesting)

      by dunkelfalke ( 91624 )

      as long as the gas is pure, it can be used for carbonating drinks.

      • Isn't it just a matter of time until it's back out into the air. I'm not sure about the body's absorption of CO2 in the digestion tract but isn't most of it, uh, belched right back out one way or another?

        • Re: (Score:3, Funny)

          by eln ( 21727 )

          Isn't it just a matter of time until it's back out into the air. I'm not sure about the body's absorption of CO2 in the digestion tract but isn't most of it, uh, belched right back out one way or another?

          Just put it in cans of RC Cola. It will never again see the light of day.

      • which then re-emit it. using it to carbonate drinks isn't sequestering it.

      • by Daimanta ( 1140543 ) on Tuesday June 23, 2009 @10:27AM (#28439527) Journal

        Two objections:

        1. The CO2 would be released into the air again
        2. I really doubt that if this plan is implemented on a massive scale(which is the only way it would be remotely useful) there would be enough demand from the carb-soda industry for the product

    • by h4rr4r ( 612664 ) on Tuesday June 23, 2009 @10:01AM (#28439103)

      Return them to HomeDepot. There your problem is solved.

      We have had places that take waste like cfls and half used paint for ages.

    • by fuzzyfuzzyfungus ( 1223518 ) on Tuesday June 23, 2009 @10:02AM (#28439119) Journal
      Umm, injecting CO2 into oil wells to enhance recovery has been used for some time, limited primarily by supplies of CO2. Injection into empty gas wells is doable as well, and somewhat more exotic approaches(like bubbling the stuff through algae farms) aren't too far outside the realm of the currently possible.

      As for CFLs, Recyclers aren't too hard to find [epa.gov]. (More generally, mercury containing florescent lamps(mostly the conventional long-tube type) have been used in commercial and industrial applications for decades; because they are cheap and last a long time. Somehow, nobody worried at all about that, until they became associated with the evil environmental movement, at which point their mercury content became a talking point. Funny how that works...)
      • More generally, mercury containing florescent lamps(mostly the conventional long-tube type) have been used in commercial and industrial applications for decades; because they are cheap and last a long time. Somehow, nobody worried at all about that, until they became associated with the evil environmental movement, at which point their mercury content became a talking point.

        No, more like because in the commercial and industrial areas, people were far more aware of the bulbs, and the dangers they presented,

        • Re: (Score:3, Insightful)

          by LordKazan ( 558383 )

          the amount of mercury in a CFL is less than the amuont of mercury you get when you eat tuna.

        • by Chris Burke ( 6130 ) on Tuesday June 23, 2009 @11:30AM (#28440473) Homepage

          No, more like because in the commercial and industrial areas, people were far more aware of the bulbs, and the dangers they presented, and were more prepared for any potential problems.

          Which turn out to be basically nothing, which is why there are florescent lights up everywhere in every office building and store you walk into and no HAZMAT teams on call to deal with broken bulbs. Yes, that's right, Wal-Mart is endangering you with the horrible danger of their dangerous lights with no regard for your safety! You should sue! :P

          I, like many people, just want to have a choice and I am getting sick of being branded as some "earth murderer" because I'm not interested in having little mercury bombs all over the place.

          Odds are that you have more mercury than 1000 CFLs in your face.

          Anyway, "earth murderer" is indeed over the top. I'm sure you wish the earth no ill. "Uninformed reactionary" is a much better term. Relax. How often do you break lightbulbs? If you aren't doing it every single day, you're safe. Worried your kids or pets will knock over a table lamp on a regular basis? Use an incandescent there. Recessed can lights? Why on earth wouldn't you use a CFL there? Cus it might spontaneously explode and give you mercury-induced brain damage?

      • Re: (Score:3, Informative)

        by moonbender ( 547943 )

        Umm, injecting CO2 into oil wells to enhance recovery has been used for some time, limited primarily by supplies of CO2. Injection into empty gas wells is doable as well, and somewhat more exotic approaches(like bubbling the stuff through algae farms) aren't too far outside the realm of the currently possible.

        You're making it sound awfully easy. There are a number of approaches, but AFAIK the tech is not there yet for long-term storage of huge amounts of CO2. There was a huge hoopla about a law passed in Germany about carbon sequestration for coal power plants; companies are experimenting with the technology, but they aren't willing to guarantee the stuff actually stays "down" for more than a couple of decades. After that, it's the governments problem. So, yes, my first reaction to TFA was that it didn't even me

    • Compact fluorescents contain mercury, which is really fun to play with. No problem.

    • but nothing on storage and disposal.

      Personally, I'd like to see them make it back into fuel. Close the cycle. I don't know how mature the technology is, but there was a news item about a catalyst which could convert CO2 into C1, C2, or C3.

    • by Geoffrey.landis ( 926948 ) on Tuesday June 23, 2009 @10:26AM (#28439507) Homepage

      It would make a lot more sense to use real trees. They don't "cost as much as a Toyota," they grow by themselves from seeds, and are self-replicating. They don't extract carbon dioxide in the form of stuff that has to be liquified and then sequestered somehow; they extract CO2 and solidify it in the form of cellulose, a material that is naturally solid at room temperature and pressure.

      Obviously, if the trees are then allowed to rot, the CO2 returns to the atmosphere, but that is an easy problem compared to the problem of sequestering CO2 for a few centuries. Just pile it up in the desert, where it won't rot. Or, heck, bury it and let geological forces compress it for a while, and you make new coal that our successors a few million years later can deal with. Wood is a heck of a lot easier to sequester than carbon dioxide!

      In short, I can't think of anything more idiotic than designing "artificial" trees, when nature has been evolving real trees optimized to do exactly this task (removing carbon dioxide from the atmosphere)-- and has had a few hundred million year head start.

      • Re: (Score:3, Interesting)

        by Chyeld ( 713439 )

        Trees work in places trees work. Trees don't work in many places, such as the urban areas where cars are more likely to be concentrated at.

        Trees are not a fire and forget tech, they require a good bit of maintence if you are attempting to use them for a purpose they require water, protection from pests and diseases, and room.

        If you check the article, the device is the size of a small trailer, and pulls out a ton of CO2 a day. Compare that with trees packed into the equivalent amount of space (even assuming

        • by Geoffrey.landis ( 926948 ) on Tuesday June 23, 2009 @10:56AM (#28439947) Homepage

          Trees work in places trees work. Trees don't work in many places, such as the urban areas where cars are more likely to be concentrated at.

          What's your point? It doesn't matter where you put the trees; there's no reason to put them in the same place where the cars are concentrated.

          Carbon dioxide is a global problem, not a local one. Put the trees wherever it makes most sense to put them.

        • Re: (Score:3, Interesting)

          by sjames ( 1099 )

          Trees aren't as much trouble as you think. Here in Atlanta, there are several abandoned buildings where trees have sprouted ON THE ROOF of their own accord. I have no idea what they're using for soil, but they certainly managed.

          Your point about the amount of CO2 captured is fair enough.

          • Re: (Score:3, Informative)

            by Chyeld ( 713439 )

            Again, in places where trees work, they work. But Atlanta has a far differnt climate then say, Phoneix, Las Vegas, LA, or even NYC. Places where space or water are premiums are going to not be the best environments, nor are places that are too hot or too cold. Yes, different climates call for different types of trees, and in theory you could get something 'green' growing almost everywhere. But at that point, aren't you putting in as much effort just to go 'green' than you would if you just plopped a couple

      • by Hythlodaeus ( 411441 ) on Tuesday June 23, 2009 @11:20AM (#28440325)

        The artificial "tree" is projected to remove as much CO2 per day as 25194 real trees.

        • Re: (Score:3, Insightful)

          The artificial "tree" is projected to remove as much CO2 per day as 25194 real trees.

          Am I the only one who smells bullshit, in this statement?

          You mean to tell me that someone came up with this particular figure, 25194 "real trees", and wasn't laughing his own ass off? And what kind of tree is a "real tree"? Is it an oak? A pine? An eucalyptus? At which stage of development of said tree is this "a real tree"? Which season?

          Isn't it ridiculous that the post was modded "informative" although it contains no information whatsoever, except for a number clearly pulled out of someone's ass.

        • by 32771 ( 906153 )

          To put it differently according to the following article:

          http://withouthotair.blogspot.com/2008/06/last-thing-we-should-talk-about.html [blogspot.com]

          "So the area of forest per person required to fix a European output of 11 tonnes of CO2 per year is 7500 square metres per person."

          However the forest also converts solar energy and CO2 into O2 and organic material. This is what CO2 storage doesn't do. Trees may not be particularly efficient at it but the storage problem should be solved by just letting them stand for some co

    • Re: (Score:3, Informative)

      by TooMuchToDo ( 882796 )
      You're aware CFLs can be recycled at your local Home Depot (as well as a variety of other local establishments) at no cost to you, correct? You just have to google "cfl recycling". Le sigh.
  • Trees (Score:3, Insightful)

    by Archibald Buttle ( 536586 ) <steve_sims7@yaho[ ]o.uk ['o.c' in gap]> on Tuesday June 23, 2009 @09:55AM (#28438987)

    Is there something wrong with real trees?

  • by s31523 ( 926314 ) on Tuesday June 23, 2009 @10:01AM (#28439101)
    C'mon, calling these things trees is ridiculous. They don't transform the "bad" CO2 into "good" O2 and H2O, they simply capture it and store it. Wow. BFD. The claim that these "trees" collect CO2 at about 1000 times faster is crap. Real trees actually transform the CO2. Lame! They should try to genetically modify trees/plants to perform more active photosynthesis in order to make them capable of pulling more CO2 out of the air in a useful manner...
    • They don't transform the "bad" CO2 into "good" O2 and H2O, they simply capture it and store it.

      Nothing can turn "bad" CO2 into "good" O2 and H2O.

      I don't know much about this "artificial tree" FTA, but what I do know is that natural trees also simply capture and store carbon. Yes, they let off O2 and H2O as part of the process, but sequestration occurs with both these artificial trees and with natural trees.

      And either way, you still have the problem of long-term storage. Dead trees release their carbon

  • by nahgoe ( 901302 ) on Tuesday June 23, 2009 @10:04AM (#28439143)
    Being a cyclist, I have no understanding of the cost of a toyota (or any other car for that matter).

    Can someone tell me how many bicycles in a toyota?

    • Re: (Score:2, Insightful)

      by maxume ( 22995 )

      It depends on the bicycle and Toyota that are involved, but I think you could rely on it being at least 25-30 smugs worth.

    • by j-beda ( 85386 )

      Can someone tell me how many bicycles in a toyota?

      Which Toyota? Which bicycle?

      The Toyota price is probably somewhere between $15000 and $40000, which is about a factor of 3 uncertainty - maybe giving a dollar amount would have been better and then followed that with something like "$xxx is about the cost of the average Toyota sold in the USA".

      The bike price could range from $100 to maybe as high as $10000, which is about a factor of 100, so seems a particularly poor choice for a unit of cost.

  • There was an interesting article on Planet Gore [nationalreview.com] discussing the replacement of chlorofluorocarbons with hydrofluorocarbons [nationalreview.com] and the unintended consequences thereof. Basically the HFCs have less effect on the ozone but are a more potent greenhouse gas. Never a dull moment!

    Planet Gore has a lot of good stuff about various green quandries, including a fair number of posts by Chris Horner (author of Red Hot Lies [amazon.com]).

  • plant more trees? They cost significantly less than a Toyota, require minimal maintenance, and handle the CO2 storage themselves. Oh, and stop cutting down the ones that are already there.
  • by Viking Coder ( 102287 ) on Tuesday June 23, 2009 @10:12AM (#28439277)

    length = one Toyota from fender to fender
    mass = one Toyota
    time = um - how long it takes a Toyota to go 1000 Toyotas in distance from a dead stop
    electric current = the amount of current from the battery in a Toyota
    thermodynamic temperature = ooh - this is a tough one...
    amount of substance = one Toyota
    luminous intensity = light from both front headlights of a Toyota on maximum brightness

    I'm not sure how to do the temperature one, but the rest all seem to work...

    • by Arimus ( 198136 )

      Temperature: factional units of a toyota expansion/concration of a toyota at standard room temperature and pressure?

    • 100 degrees = the temperature change of a toyato of water produced when you burn a toyota of wood under it.

  • by fataugie ( 89032 )

    When I read stories like this, I combine swear words in combinations I never thought possible.

    So when they build one or two of these "Farms" and find out....whoops, we underestimated their effectiveness and costs...then what?

  • A question is would you rather walk through a thousand acres of forest or an acre covered with these high-tech porta-cabins?
  • FTFA

    "Broecker told CNN the units could stand in the middle of Australia, for example, and their presence wouldn't significantly disrupt the atmospheric distribution."

    Except for the minor problem of being fuck all in the middle of Australia - including massive power generation facilities require to run them

    I am not sure if it is related, but sometime in the last year I saw some reality/doco TV program that was attempting to produce a proof of concept of such an artificial tree in a fixed time frame. What

  • we lower the efficiency of burning fossile fuels? You know that sounds like a really good idea to me....

  • If only there was something you could just plant in the ground that would grow on it's own, powered only by water and sunlight, that would do the same thing..
  • Millions of little smog reducing machines stuck under millions of cars, which have to meet stringent weight/price/space requirements to be practical - or gigantic smokestack scrubbers like algae biofuel this one? [csmonitor.com]

    Trying to mop up all the problems from millions of cars is the real problem here.

    Instead, let's work on moving to all electric cars. This will centralize the pollution at the power generators and then you can take whatever steps are necessary to minimize it without having to worry about catalyt

  • Algae Need This (Score:3, Interesting)

    by phantomcircuit ( 938963 ) on Tuesday June 23, 2009 @10:26AM (#28439509) Homepage

    Algae farms which could produce fuel need large quantities of concentrated CO2 to function. They would be a perfect match with these artificial trees.

  • Hmmm... (Score:3, Interesting)

    by Mr Z ( 6791 ) on Tuesday June 23, 2009 @10:35AM (#28439685) Homepage Journal
    New business plan...
    • Build concentrated solar power plant in the middle of the desert
    • Build a ton of these CO2 collectors driven off the solar power
    • Sell as many carbon credits as possible
    • Sell the remaining electricity into the grid
    • PROFIT!

    Could it work? Now where to put all that liquid CO2?

  • Costs and pollution during:

    Building, shipping, installation, maintenance, removal, replacement.

  • At the end of the day we have got to do something about the "carbon-in-the-atmosphere" problem and while this idea might not be fantastic it could be a step in the right direction. I actually think this is probably just the same carbon capture technology that they are planning on fitting to coal fired power stations (good overview in tabs - http://news.bbc.co.uk/1/hi/uk_politics/8014295.stm [bbc.co.uk]) in which case it would make more sense to capture it at source and not waste energy in transmission.

    Personally I woul

  • by Epeeist ( 2682 ) on Tuesday June 23, 2009 @11:49AM (#28440815) Homepage

    This sounds disturbingly like my wife's argument for buying things in a sale:

    W; "I just saved [x] pounds!"
    H: "How did you do that?"
    W: "I bought [unneeded object] for [y] pounds in the sale, it was [x + y] pounds before"
    H: "But we didn't need [unneeded object]!"

    [fx]Wife smashing husband over head with sabre[/fx]

    Wouldn't it be better not to generate the CO2, or at least minimise its production, in the first place?

  • FTA.. (Score:3, Funny)

    by sqldr ( 838964 ) on Wednesday June 24, 2009 @05:07AM (#28450573)

    "LONDON, England (CNN) -- Scientists in the United States are developing.."

    Wait.. where?

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