Forgot your password?
typodupeerror
Earth Technology

Removing CO2 From the Air Efficiently 487

Posted by kdawson
from the install-anywhere dept.
Canadian scientists have created a device that efficiently removes CO2 from the atmosphere. "The proposed air capture system differs from existing carbon capture and storage technology ... while CCS involves installing equipment at, say, a coal-fired power plant to capture CO2 produced during the coal-burning process, ... air capture machines will be able to literally remove the CO2 present in ambient air everywhere. [The team used] ... a custom-built tower to capture CO2 directly from the air while requiring less than 100 kilowatt-hours of electricity per tonne of carbon dioxide."
This discussion has been archived. No new comments can be posted.

Removing CO2 From the Air Efficiently

Comments Filter:
  • Natural device? (Score:5, Insightful)

    by TheMidnight (1055796) on Wednesday October 01, 2008 @02:59AM (#25215031)

    Don't we have a device that removes CO2 from the air? I thought they were called "trees."

    • by Fluffeh (1273756) on Wednesday October 01, 2008 @03:16AM (#25215115)
      Oh honestly, you green bottomed hairy hippie! Why plant trees that will cleanly and effectively remove the carbon from the air, when we can invent a MACHINE to do it that will use electricity and require parts and labour and all that? You greenies and your whacky nature ideas. Honestly! How exactly do trees generate jobs?

      I suppose you eat dolphin safe tuna as well?!
      • by Crudely_Indecent (739699) on Wednesday October 01, 2008 @04:42AM (#25215547) Journal

        How exactly do trees generate jobs?

        Well...people could be paid to plant them. Yeah, I know that trees can do this on their own....but can they do it in nice neat rows?

      • by Captain Hook (923766) on Wednesday October 01, 2008 @04:50AM (#25215585)

        I suppose you eat dolphin safe tuna as well?!

        No, but I do eat tuna safe dolphines. hmmm

      • Re: (Score:3, Informative)

        by psychosol (1275702)
        Its True! Trees do remove CO2 from the air! The problem starts, and this is where there is much misunderstanding, with what happens to the carbon in the long term. A tree will absorb a large amount of CO2 during its lifetime, but when after its lifetime, that carbon is released again as the tree decays, or is burned as fuel, etc. The point of CCS is to place the captured carbon in a state that it can be stored for the long term (1000's of years). The problem isn't so much that we are performing process
    • Re:Natural device? (Score:4, Insightful)

      by Anonymous Coward on Wednesday October 01, 2008 @03:17AM (#25215121)

      They won't be making a pile of cash out of trees.

      Can't resist:

      1) Identify a possible source of trouble
      2) Invent a fix, no matter how convoluted it is
      3) Patent it and market it
      4) Profit

      Just wonder how much do we have to wait for a fart capture device (cow farts are actually a major source of trouble)

      • by marco.antonio.costa (937534) on Wednesday October 01, 2008 @03:22AM (#25215141)

        Man! Cut it out!

        It's THREE steps, not four, and you CAN'T specify the intermediate one! Jeezuz...

      • by Macthorpe (960048) on Wednesday October 01, 2008 @03:45AM (#25215255) Journal

        Just wonder how much do we have to wait for a fart capture device

        Thank you, Argentina. [bbc.co.uk]

      • Re: (Score:3, Informative)

        Just wonder how much do we have to wait for a fart capture device (cow farts are actually a major source of trouble)

        This has already been done in Holland - no waiting required, therefor - a university study group has work in progress on the subject of cow farts. There are groups of cows standing around with cylinders strapped to their backs in order to (forgive the word) fuel this study. Saw it on /.

      • by Enter the Shoggoth (1362079) on Wednesday October 01, 2008 @05:33AM (#25215801)
        Actually, it's a common misconception that "cow emissions" are from cow's farting, it's actually the way a ruminant will burp during the processing of a cud that produces large volumes of methane (which is of course more troubling than CO2 emissions)

        They won't be making a pile of cash out of trees.

        Can't resist:

        1) Identify a possible source of trouble 2) Invent a fix, no matter how convoluted it is 3) Patent it and market it 4) Profit

        Just wonder how much do we have to wait for a fart capture device (cow farts are actually a major source of trouble)

        • Re: (Score:3, Funny)

          by Linker3000 (626634)

          So we need to kill all the vegetarians, right?

      • Re: (Score:3, Informative)

        Actually methane from bovines is expelled in the form of burps, very little methane is farted out.

    • by Ihlosi (895663) on Wednesday October 01, 2008 @03:17AM (#25215123)

      Don't we have a device that removes CO2 from the air? I thought they were called "trees."

      I hooked a tree up to 100kW, and it added CO2 to the air instead.

      • by DancesWithBlowTorch (809750) on Wednesday October 01, 2008 @01:39PM (#25221633)
        Hey guys, this is the physics police talking here. I'm sorry, but we'll have to enforce the laws of thermodynamics in this case.

        According to David MacKay [withouthotair.com]:

        The unavoidable energy requirement to concentrate CO2 from 0.03% to 100% at atmospheric pressure is kT ln 100/0.03 per molecule, which is 0.13 kWh per kg. The ideal energy cost of compression of CO2 to 110 bar (a pressure mentioned for geological storage) is 0.067 kWh/kg. So the total ideal cost of CO2 capture and compression is 0.2 kWh/kg. According to the IPCC special report on carbon capture and storage, the practical cost of the second step, compression of CO2 to 110 bar, is 0.11 kWh per kg. (0.4 GJ per t CO; 18 kJ per mole CO; 7 kT per molecule.)

        In other words: It'll be at least 200kW per tonne, unless they think the CO2 will somehow magically compress itself to be stored, which is not going to happen. That, or they just invented a perpetuum mobile.

    • Re:Natural device? (Score:5, Interesting)

      by TarrVetus (597895) <[moc.liamg] [ta] [suteVrraT]> on Wednesday October 01, 2008 @03:28AM (#25215177)
      This may be Bad Math, but... The article says, "The tower unit was able to capture the equivalent of approximately 20 tonnes per year of CO2 on a single square metre of scrubbing material -- which amounts to the average level of emissions produced by one person each year in North America." A page I dug up [carbonify.com] claims a single tree removes "on average 50 pounds (22 kg) of carbon dioxide annually over 40 years."

      The scrubber sounds pretty effective. No waiting for it to grow, and it's more space-efficient, which is good for cities and industrialized areas.
      • Re:Natural device? (Score:4, Interesting)

        by Anonymous Coward on Wednesday October 01, 2008 @03:42AM (#25215243)

        This may be Bad Math, but... The article says, "The tower unit was able to capture the equivalent of approximately 20 tonnes per year of CO2 on a single square metre of scrubbing material -- which amounts to the average level of emissions produced by one person each year in North America." A page I dug up [carbonify.com] claims a single tree removes "on average 50 pounds (22 kg) of carbon dioxide annually over 40 years."

        The scrubber sounds pretty effective. No waiting for it to grow, and it's more space-efficient, which is good for cities and industrialized areas.

        Yep, and we only ned 450,000,000 of them to keep up with the carbon output of the denizens of North America.

        It's not clear from the wording whether that includes the output of North American industry, or just the habits of individuals.

      • Re: (Score:3, Interesting)

        by Wyatt Earp (1029)

        And trees which are being GM'ed to grow faster and/or remove more CO2 are under attack by eco-terrorists.

        I'm not going to search, but I'd thought that grasslands were more efficient CO2 sinks than trees

      • by TheLink (130905)
        For comparison:

        Poplar trees are about 10 tons per acre. Which is about 2.5kg of wood per square meter.

        From: http://www.physorg.com/news75568548.html

        And oil palms produce about 0.6 kg of oil per square metre.
      • by Candid88 (1292486)

        Yea but planting a few billion tree's and letting them grow themselves is a heck of a lot easier than building hundreds of millions of these towers.

      • by jambox (1015589)
        Yeah trees grow real slow. But over the years a tree will still soak up tons of CO2, plus they cost nothing, there's no maintenance and you get a useful resource out of them at the end. Also you can pollard them to speed things up.
      • by mpe (36238)
        This may be Bad Math, but... The article says, "The tower unit was able to capture the equivalent of approximately 20 tonnes per year of CO2 on a single square metre of scrubbing material

        How often are you going to have to remove this material? Probably fairly frequently considering that it is going to be accumulating something like 55kg per day.

        The scrubber sounds pretty effective. No waiting for it to grow, and it's more space-efficient, which is good for cities and industrialized areas.

        Trees are fai
        • by fprintf (82740) on Wednesday October 01, 2008 @07:42AM (#25216489) Journal

          Trees are fairly "low maintainence" and produce at least one useful by product. Some (including one which should be obvious to Canadians) produce more than one useful product.

          Hockey sticks?

        • Re:Natural device? (Score:4, Informative)

          by Markspark (969445) on Wednesday October 01, 2008 @08:04AM (#25216643)
          The scrubber uses Sodiumhydroxide and Calciumhydroxide that are circulated and regenerated in the process. The power demand comes from separating the CO2 from the CaCO3 back into Ca(OH)2.
          But you are correct in the fact that this would require maintenance, since there's no such thing as maintenance free pumps.
          However i still feel if this could be a good solution, if it's cost and energy efficient, and being financed by carbon-taxing, and last but not least, F/OSH (free/opensource hardware).
          • Re: (Score:3, Insightful)

            by ThosLives (686517)

            It is impossible for a device like this to be cost efficient in the present. It is unknown if it is cost efficient in the long run. Here's what I mean (caveat: I'm focusing wholly on economics here, not politics):

            These devices require a fixed cost to produce (in terms of materials not available for other machines, labor not available for other activities, cost of required associated infrastructure, etc.) and a recurring cost to operate (energy not available for other things, maintenance labor and parts no

    • Re: (Score:3, Insightful)

      by bakuun (976228)

      Don't we have a device that removes CO2 from the air? I thought they were called "trees."

      Yes, but when the trees eventually die they are decomposed and release the CO2 into the air again (or in the case of biofuel, they release it into the air again when burned). It is a carbon-neutral system, both when left alone and when used as a fuel.

      I imagine an approach like this would be considerably less efficient than, say, putting CCS devices on coal plants. If it "costs" 100 kWh / tonne of CO2 at a normal location, you'd most likely get better efficiency if this was done where the air concentratio

      • Re: (Score:3, Interesting)

        by rbanffy (584143)

        You can always capture their carbon and tuck it away in a sealed mine.

        At the office, I joke that by printing a lot you are actually helping reduce CO2 because paper comes from fast-growing trees that eat up a lot of carbon in the process. As far as you don't burn it, you are reducing your carbon footprint. If we gathered all the paper we have to print and buried it deep we would be both reducing carbon in our biosphere and offering a nice stockpile of fossil fuel for the cockroach civilization that will fol

    • by mpe (36238)
      Don't we have a device that removes CO2 from the air? I thought they were called "trees."

      Any green plant will do. How difficult would it be to pipe the exhaust from a coal fired powerstation through some greenhouses. Which is the obvious place to put a "greenhouse gas" in the first place :)
    • Re:Natural device? (Score:4, Interesting)

      by OeLeWaPpErKe (412765) on Wednesday October 01, 2008 @04:55AM (#25215603) Homepage

      And now the catch ... while this tower is beyond inefficient :

      Coal produces 2.117 pounds per kwh.
      = 0.000960255047 tonne per kwh.
      = 1041 kwh per tonne Co2

      This needs about 10% of that power, combined with some 15% transmission loss, and the fact that this is a lower bound over time (obviously if we lower athmospheric co2 this cost will raise).

      That means we need 23% or about 1/4th of total energy to merely break even. Petroleum and gas aren't that much better, and aren't feasible over even the medium term anymore. To actually make a difference we'd need 50% of all energy produced, which means our generating capacity needs to rise by 100% (and not 50% because if we raise it by 50% we'd have 1.5 times the energy which would be divided into 0.75 for carbon nonsense and 0.75 for us. So we'd need 200% of the energy making it 1 unit for us, and 1 unit for co2 nonsense).

      That's not exactly good news, is it ? It gets worse.

      Trees are much worse in efficiency than this. Yes, they do produce their own energy. They're however 2% efficient solar panels (so in reality a tree presents lost energy, in that a solar panel could have been standing where the tree stood and produce about 20 TIMES more energy, making these towers more efficient even if trees were 100% efficient chemical machines, since that would only give them 5% of the efficiency of the solar panels).

      Well trees do about 650 kg per tree per year. Needless to say this is beyond pitiful. Using solar panels to power a tower like this would replace a forest in about 100 square meters. Combine this with the need to double generating capacity in order to make the towers work and you'll see exactly where this would be going in the real world.

      • Re: (Score:3, Interesting)

        by Sj0 (472011)

        One of the major problems with algae-based biofuel is a lack of easy to obtain concentrated carbon dioxide.

        So desert + CO2 machine + solar panels + algae = self-powered biofuel engine

    • Re:Natural device? (Score:4, Interesting)

      by AliasMarlowe (1042386) on Wednesday October 01, 2008 @06:56AM (#25216219) Journal

      Don't we have a device that removes CO2 from the air? I thought they were called "trees."

      Well, yes... but the rate at which trees remove CO2 from the air is not very high. Moreover, left to nature, much of that CO2 is usually released again at the end of the tree's life, when it usually rots slowly. If, however, the tree is harvested for human use, most of the CO2 may be released rapidly (firewood), or some of it may be stored for decades to centuries (construction, paper).

      Either way, the net rate of fixation of CO2 is rather limited, and far less than the rate of release of fossil carbon. Nature required many millions of years for plants to convert CO2 into reserves of fossil hydrocarbons.

      CO2 has also been removed from the atmosphere via the oceans. Many shelly organisms use dissolved CO2 to build their shells. On death, some of these sink, eventually forming carbonate sediments. Geologic processes have been releasing CO2 from carbonate sediments at a similar (but probably lower) rate.

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

      In modern times, industry has been releasing fossil carbon as atmospheric CO2 at a rate some orders of magnitude faster than the net rate of removal of CO2 by plants and shelly creatures. There's the rub. To reverse the buildup of atmospheric CO2, we need something beyond mere forests and diatoms.

  • Is it effective? (Score:3, Insightful)

    by Yetihehe (971185) on Wednesday October 01, 2008 @03:00AM (#25215043)
    Yeah, but how much energy does generating one tonne of CO2 give? It still just capturing CO2, they need still more energy to eventually convert it to fuel [wired.com]
    • Re: (Score:2, Insightful)

      by TooMuchToDo (882796)

      I assume that this device would be used with clean renewable energy sources to remove CO2 we've already pumped into the atmosphere. So, you'd run this thing at night when energy prices are low (around 1-2 cents/kwH) to help bring the atmosphere back into balance (and of course, you must be using wind or some other non-fossil fuel for electicty, duh).

      A couple of these machines by themselves won't do much, but hundreds of thousands of them powered by coastal wind farms or solar farms in the desert could defin

      • Re:Is it effective? (Score:4, Interesting)

        by TooMuchToDo (882796) on Wednesday October 01, 2008 @03:07AM (#25215073)

        I almost forgot, these machines and the clean energy they need could be paid for using carbon credits. Nuclear energy in Northern Illinois (where I live) can be had for about a penny per kWh between midnight and 4 am (when base load is extremely low). So, if they can pull out a ton of CO2 from the atmosphere for 100 kwH of energy, you're looking at between $1-$2/ton in energy costs (capital costs for the equipment needs to be considered, as well as people to maintain everything).

    • by zobier (585066)

      Yeah, but how much energy does generating one tonne of CO2 give?

      Given approximately 1.5 lb CO2/kWh, somewhere around 1400 kWh.

    • Probably Not, IMHO (Score:3, Insightful)

      by Gazzonyx (982402)
      You mean, do the laws of thermodynamics still apply?
      Yes.
      It will always take more energy to convert from one form of energy to another; the trick is using 'free' energy with minimal impact for a catalyst and accepting that the return is always marginalized. We also get diminishing returns on our attempts to make more efficient systems... the energy to create the systems climbs as the returns on said systems becomes less. Just gotta' accept that part of the game, 'cause you can't not play.
  • by JumperCable (673155) on Wednesday October 01, 2008 @03:02AM (#25215053)

    It's solar powered. No need to pay any electric bills. Maintenance & care is cheap dirt.
    http://pws.byu.edu/tree_tour/images/tree116small.jpg [byu.edu]

  • "[The team used] ... a custom-built tower to capture CO2 directly from the air..." Is it just me, or did everyone else also receive that instant mental image of the [nuked] atmosphere processor from LV-426?
  • by invisibleairwaves (1266542) on Wednesday October 01, 2008 @03:13AM (#25215097)
    > Canadian scientists have created a device that efficiently removes CO2 from the atmosphere.

    As a Canadian, I have to say I'm disappointed in my fellow countrymen. Just when you thought global warming would make our climate mildly tolerable, they go and mess it all up.

    Thanks, guys. I'm sure you'll regret this in a few months. No, I will not shovel your driveway.
  • Since a coal fired power plant produces 100kg of CO2 to produce the electricity to remove one ton, you will have to remove that to, or 1,111kg. And then you will have to store it for a billion years.

  • by Hays (409837) on Wednesday October 01, 2008 @03:14AM (#25215105)

    Assuming that 1 tonne = 1000kg, this machine requires approximately 1 kilowatt hour of electricity to remove 10kg of Carbon Dioxide from the atmosphere. How efficient is this?

    From http://www.glumac.com/section.asp?catid=140&subid=152&pageid=564 [glumac.com]

    "For home energy use, carbon dioxide emissions vary widely from state-to-state and from day-to-day. The national average is about 1.3 pounds of carbon dioxide for every kilowatt-hour of electricity used in your home."

    Not bad. If it really works, you can redirect 10 to 15% of your electricity to achieve Carbon neutrality.

  • I have always found it curious all the attention to coal-powered generating plants re: CO2, but nobody ever mentions the fact that natural gas processing plants extract--and release directly into the atmosphere--tons of CO2 every year.

    • by zippthorne (748122) on Wednesday October 01, 2008 @03:57AM (#25215329) Journal

      Probably because that gas was coming out anyway, as the wells are tapped for the oil in them. The only thing the natural gas plants do is reduce the overall need for the oil (by taking up some of the load) and convert greenhouse gases into weaker greenhouse gases.

    • Re: (Score:2, Informative)

      by rukcus (1261492)
      Energy generation can't be measured in total emissions, but rather by emissions per unit energy produced.

      Coal: 1160 g of CO2/kWh
      Gas: 400 g of CO2/kWh
      PV Solar: 120 g of CO2/kWh (manufacturing)
      Nuclear: 55 g of CO2/kWh
      Biomass: -4 kg of CO2/kWh

      Of course, nuclear has its own special disposal requirements, but it is less polluting in terms of green house gases.

      Source: Wiertzstraat, Wise, Coming Clean: How Clean Is Nuclear Energy? Stichting GroenLinks in EU; Brussels, Belgium. Oct 2000.
    • Re: (Score:3, Informative)

      by Viol8 (599362)

      When you burn gas you get less CO2 for the same energy output than you do from coal because part of the reaction is reacting the hydrogen in the gas with oxygen which produces water so gas plants arn't quite so bad for the enviroment.

      CH4 + 2O2 -> CO2 + 2H20

      Coal however is almost 100% carbon (apart from some minor impurities).

  • "requiring less than 100 kilowatt-hours of electricity per tonne of carbon dioxide" how many kilowatt hours does it take to produce a tonne of carbon dioxide using a gas / oil / coal powerplant?
    • Re: (Score:3, Interesting)

      shoulda googled before i posted:

      *snip*
      According to these studies, a new coal fired power plant will release between 1.96 (PLC) and 2.09 (DOE) pounds of CO2 per kilowatt hour of operation. For our report, we assume that any given coal-fired power plant will emit 2 pounds of CO2 per kilowatt hour.
      A power plant with a one megawatt (1,000 kilowatts) name plate capacity will produce the equivalent of 8,760,000 kilowatt hours annually at full operation -- that is, 8,760 hours multiplied by 1,000. At this ra
  • by Chrisq (894406) on Wednesday October 01, 2008 @03:22AM (#25215147)
    I have seen a number of proposals before that make the very basic mistake of using a material to absorb C02 that gives of C02 during manufacturer. Until I see details I will take this with a pinch of salt.

    If I had a penny every time someone says "just absorb it all with lime" I would be able to afford a chocolate bar. Besides which, looking at emissions per kw/h [npcil.nic.in] you had better not use coal or oil to power this, and even with Gas produced electricity the benefit is marginal.
  • yes, lets fuck around with the atmosphere a little more.
  • by Anonymous Coward

    I still think creating a time travel device, going back and assassinating Al Gore and IPCC key members will end this global warming problem.

    While we're at it, I hope you won't mind if we put two leads in Col. Korn's head. Later, I'd like to murder Havermeyer and Appleby. After we do those two, we can kill McWatt.

  • by Mashiki (184564) <mashiki@gmail. c o m> on Wednesday October 01, 2008 @03:33AM (#25215199) Homepage

    Goto where the farmers are burning down the rain forests, teach/give/train them how to plant high yield crops and stop them from clear cutting/burning them down. And shock...you'll get somewhere.

    Sometimes the most obvious solutions are sitting in front of their faces.

    • by dave420 (699308)
      What happens to those crops once they're destroyed? How do the crops get to wherever the market for them is?
    • Re: (Score:3, Funny)

      by Hao Wu (652581)

      Go to Neptune, sample the core, and return it to the earth.
       
      I typed it out easily enough, so it must be that simple!

  • A company could, in principle, contract with an oilsands plant near Fort McMurray to remove CO2 from the air and could build its air capture plant wherever itâ(TM)s cheapest -- China

    I had to laugh at that, for once its not because of cheap labour that the jobs are being outsourced.

    It does raise the issue however, china is already let off the Kyoto treaty as its considered a developing nation, now are they are going to reap economical benefits of other developed nations by outsourcing their CO2.

    Seems like a double win for China for all the wrong reasons.

  • Space missions (Score:4, Insightful)

    by Anonymous Coward on Wednesday October 01, 2008 @03:46AM (#25215267)

    expedient and efficient removal of CO2 at atmospheric concentrations could have profound implications in space.

    Currently, CO2 is scrubbed using lithium salts, which are not only heavy, but also caustic, and have a limited service life before requiring replacement.

    A purely electric, and solid state device capable of continuous operation would allow for superior space vehicle designs which could theoretically operate much longer than currently available ones.

    If they discover a way to electronically reduce the carbon dioxide into elemental carbon, things will be even more interesting.

  • Storage Issue (Score:3, Insightful)

    by 3HackBug77 (983153) on Wednesday October 01, 2008 @03:49AM (#25215281) Homepage
    But the big question is where is all this CO2 going to go. We have the ability to store CO2, but eventually we are going to run out of room to store it all, and even worse, if it leaks you've screwed over the area around the storage. I can't imagine that storage containers would last forever too, eventually, we would have to do something with it all.
  • Caution (Score:2, Interesting)

    by bytesex (112972)

    I really, really wouldn't do all this 'CO2 from the air removing' until we're 100% sure that 1) it causes global warming, 2) global warming is bad and 3) our natural mechanisms are somehow inadequate at the moment. And even then, I mean, sure - put a filter on that chimney, but don't start removing it from places where trees (or plankton) might be hungry for it, making our ecosystem even more unstable.

    • Re: (Score:3, Insightful)

      by Viol8 (599362)

      1) CO2 does cause heating of the atmosphere. Thats basic physics and is not up for debate.

      2) Global warming might not be bad in the long term scheme of things but its bad for the enviroment (and ourselves) as we know it.

      3) Given that current natural mechanisms can't cope with the amount of CO2 we're chucking into the atmosphere then its pretty obvious they're inadequate to the needs of clearing up our mess.

  • by scottme (584888) on Wednesday October 01, 2008 @03:51AM (#25215293)

    This extraction of CO2 from the atmosphere is all well and good, but are there any reliable and cost-effective ways to store it or dispose of it?

    • All we need to do is persuade plankton to go on a binge.

      • Re: (Score:2, Interesting)

        by wierd_w (1375923)
        we can do this by pumping the carbon dioxide down deep under the ocean surface into the deep, mineral rich water below. The bubbling action will not only dissolve a goodly portion of the CO2 into the ocean water, but will also bring those deep minerals to the surface, which would initiate a kelp and algae bloom. It could have neat fringe benefits in that it could be used to promote commercial fisheries.
  • ... but what will they do with the CO2 once they have it? Storing it under ground would solve the problem for us (maybe), but what of future generations. If they however would be able to "turbo grow" trees from it, or make some industrial breaking up of the molecule efficient, then I see some use in it.
    • by logicnazi (169418) <logicnazi@gmail. ... minus herbivore> on Wednesday October 01, 2008 @05:03AM (#25215649) Homepage

      First of all don't diss the benefits of pushing problems off to the future.

      I mean the only real problem of CO2 is the cost of energy. We want energy and produce CO2 by running an energy positive chemical reaction (burning). If energy were sufficiently cheap we could simply take the CO2 and transform it into some non-greenhouse form of carbon.

      Energy gets cheaper over time, the same amount of CO2 will be less of a problem for future generations with their superior technology and better infrastructure. Besides, it was underground to start with so long as it doesn't leak that seems like a fine place to leave it.

  • by mqduck (232646)

    I suppose I'm being a troll, but how many of these CO2 removing thingies have to be invented till they exist somewhere outside Slashdot?

  • I say, let the terraforming begin!

    Place these things all over the martian surface and make em solar powered!
  • Great (Score:3, Insightful)

    by Errtu76 (776778) on Wednesday October 01, 2008 @06:14AM (#25215983) Journal

    We have found the excuse we need to continue polluting the air. Way to go, humanity!

  • by Ambitwistor (1041236) on Wednesday October 01, 2008 @09:02AM (#25217169)

    First, this isn't a new idea. Artificial air capture of CO2 has been proposed for some time; a noted proponent of this idea is Klaus Lackner [columbia.edu]. I don't think this new group has made a huge breakthrough in the technology. The basic problem is that it's (a) expensive, and (b) you have to put the carbon somewhere.

    As for (a), it's currently cheaper to just capture the CO2 at large point sources like coal plants. On the other hand, that only gets some of the emissions. While coal plants are the most serious source of CO2 right now, adding capture to power plants doesn't capture emissions from cars and other small sources. Still, right now it's easier to just make more fuel efficient cars than try to capture the CO2 they emit.

    As for (b), the sequestration problem is shared by any carbon capture technology (air capture or not). The main solutions are to pump it into geological formations in land or under the sea, or to convert it to solid form. The latter is relatively expensive and energy intensive. Storing it in the deep ocean is difficult to do on a large scale. On land there are serious limitations on how fast you can pump CO2 into a formation without pressure fractures and leaks, and even then there is a wide variety of formations whose ability to store CO2 varies dramatically. It requires careful siting, monitoring, etc. and you still have to worry about leaks, not to mention all the legal problems with people worrying about the CO2 acidifying the groundwater and leeching out heavy metals.

    That being said, I think this technology definitely needs a lot of R&D aimed at it, because though expensive and difficult, it's a fallback position to reduce CO2 levels if energy efficiency and alternative energy measures don't do enough of a job.

  • by IcyHando'Death (239387) on Wednesday October 01, 2008 @09:30AM (#25217469)
    More details from http://www.cbc.ca/technology/story/2008/09/30/carbon.html [www.cbc.ca]

    The tower acts as a scrubber, with sodium hydroxide, also known as caustic soda, reacting with air blown into its base. A metal honeycomb system inside the tower slows down the flow of caustic soda, allowing it to efficiently scrub CO2.

    While Keith said the technology isn't new -- it's been used since the 1950s in industrial processes that call for carbon dioxide-free air -- he believes his team has surmounted one of the two biggest obstacles to CO2 capture.

    For the system to be effective, it must remove more carbon dioxide from the air than it emits as a byproduct of the energy used to run the scrubber. This summer's experiment showed that can be done, said Keith.

    He estimates that if the electricity used to run the ambient air scrubber were to come from a coal-fired power plant -- a heavy emitter of CO2 -- he could capture 10 times more CO2 than the coal plant emitted.

  • by toby (759) * on Wednesday October 01, 2008 @09:53AM (#25217839) Homepage Journal
    Let's stop cutting down the Amazon [google.ca] already, shall we?

"Your mother was a hamster, and your father smelt of elderberrys!" -- Monty Python and the Holy Grail

Working...