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Removing CO2 From the Air Efficiently

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."

17 of 487 comments (clear)

  1. Natural device? by TheMidnight · · Score: 5, Insightful

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

    1. Re:Natural device? by Anonymous Coward · · Score: 4, Insightful

      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)

    2. Re:Natural device? by bakuun · · Score: 3, Insightful

      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 concentration of CO2 was high. Such as.. at the top of a coal-plant chimney where the CO2 concentration is going to be a great deal higher than the average concentration in the atmosphere.

    3. Re:Natural device? by archeopterix · · Score: 3, Insightful

      [...] another few degrees would be enough to make them net CO2 emitters, rather than the absorbers they currently are

      I call bullshit on this one. As long as plants need carbon to build their bodies, they will be CO2 absorbers, at least until they die and decompose.

    4. Re:Natural device? by rbanffy · · Score: 3, Insightful

      I think oceans also do a pretty good job at that. And at the end of the chain you even get more fish (which is, to a certain extent, fixed carbon).

    5. Re:Natural device? by MightyYar · · Score: 4, Insightful

      Cant we just grow up now and realise we have to
      be moderate in our consumption of the planets resources instead of trying to trick our way out ?

      I don't think you understand human nature. Your solution requires changing a significant percentage of the population's behavior - I don't give it much chance of success.

      --
      W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
    6. Re:Natural device? by jambox · · Score: 3, Insightful

      Some of it sticks around but not sure how much.

      But that isn't the point. You can use the wood for making stuff and so it hangs around as paper or a table for years. It all eventually goes back of course but if we were to use more paper and less plastic, you'd be storing a lot of it temporarily and the amount stored in "the system" would be higher.

      --
      You thought you could break the laws of physics without paying the PRICE?
    7. Re:Natural device? by es330td · · Score: 3, Insightful

      The good news about a rise in CO levels is that it could have a limiting effect on the production of CO2 producers. We may kill off all the oxygen breathing life, but hey, we saved the planet so it's okay, right?

    8. Re:Natural device? by Sj0 · · Score: 3, Insightful

      Paperwork is SO 1929. Everyone does things electronically now. You can bankrupt the nation entirely over the Internet now!

      --
      It's been a long time.
  2. If they want to remove CO2... by Mashiki · · Score: 5, Insightful

    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.

    --
    Om, nomnomnom...
  3. Space missions by Anonymous Coward · · Score: 4, Insightful

    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.

  4. Storage Issue by 3HackBug77 · · Score: 3, Insightful

    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.

  5. Re:Natural Gas Processing Plants? by zippthorne · · Score: 3, Insightful

    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.

    --
    Can you be Even More Awesome?!
  6. Re:Reference point to CO2 emissions by jimdread · · Score: 3, Insightful

    You've still got the energy cost of disposing of the CO2, by burying it or whatever. It has to be taken out of the carbon cycle completely.

    Then only way you can take it completely out of the carbon cycle is to blast it into space on a rocket. Carbon, being the fourth most abundant element in the universe, is everywhere on the planet. Fossil fuels, such as coal and oil, are made of fossilized plants and animals. In other words, fossil fuels are just as much part of the carbon cycle as carbon dioxide, plants, limestone, marble, kittens, and methane. Think about how the carbon got into the coal. It's part of a cycle. A very long cycle.

  7. Re:CO2 is good by Ambitwistor · · Score: 4, Insightful

    A warmer planet is good.

    Good for who? Norway? Or West Africa?

    A warmer climate leads to more arable land and longer growing seasons.

    Depends on where you are. If your plants are temperature limited in a temperate climate, maybe. If they're already in a warm climate, maybe not. And don't forget precipitation. When rain belts get shifted around, a lot of people end up unhappy.

    CO2 is good - it is the world's best fertilizer.

    This has got to be the most oversold benefit of CO2. CO2 fertilization helps, up to a point, if you have C3 photosynthesizers; C4 plants don't benefit. But direct manipulation FACE experiments show that this effect quickly saturates, and CO2 is often not the rate-limiting nutrient in photosynthesis; often it's water or nitrogen availability. The initial promise of CO2 fertilization hasn't really panned out; see here. It does help, but it doesn't quite help as much as one thinks, and it is often more than offset by negative climate changes.

    Of course, all recent evidence points to warming having ended,

    I hate to break it to you, but 10 years of below-average warming in a highly noisy system doesn't exactly overturn anthropogenic global warming.

    and having been due to natural climate variability and/or solar cycles.

    Natural climate variability counts against your claim, not for it. See the above: natural climate variability is quite large on short time scales, which makes short-term trends very unreliable evidence of anything. Over the long term, "natural climate variability" utterly fails to account for temperature trends over the 20th century; the only really long term cycles within the climate system itself are oceans, and the space/time pattern of ocean warming indicates the atmosphere is warming the ocean, not the other way around. Turning to external influences, there are solar cycles. Solar trends have been pretty much flat since the 1950s, and completely disagree with the warming experienced since then. They can account for some of the warming in the early 20th century, but very little of it since then.

  8. Frankly, I'd rather have trees by toby · · Score: 3, Insightful

    Let's stop cutting down the Amazon already, shall we?

    --
    you had me at #!
  9. Physically impossible! by DancesWithBlowTorch · · Score: 4, Insightful
    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:

    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.