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DoE Considers Artificial Trees To Remove CO2

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."

30 of 418 comments (clear)

  1. More hair-brained ideas for "Global Warming" by swaha · · Score: 4, Insightful

    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.

    1. Re:More hair-brained ideas for "Global Warming" by LordKazan · · Score: 3, Interesting

      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]

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    2. Re:More hair-brained ideas for "Global Warming" by h4rr4r · · Score: 4, Informative

      Return them to HomeDepot. There your problem is solved.

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

    3. Re:More hair-brained ideas for "Global Warming" by fuzzyfuzzyfungus · · Score: 4, Interesting

      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. (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...)

    4. Re:More hair-brained ideas for "Global Warming" by Anonymous Coward · · Score: 5, Informative

      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

    5. Re:More hair-brained ideas for "Global Warming" by alchemist68 · · Score: 5, Interesting

      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.

    6. Re:More hair-brained ideas for "Global Warming" by LordKazan · · Score: 4, Informative

      i'm not wrong, this has been demonstrated. proven. it's simple university physics.

      there is a reason why triple points of substances are given at temperature AND pressure.

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    7. Re:More hair-brained ideas for "Global Warming" by Daimanta · · Score: 4, Insightful

      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

      --
      Knowledge is power. Knowledge shared is power lost.
    8. Re:More hair-brained ideas for "Global Warming" by sunking2 · · Score: 4, Funny

      Oh sure, until you wake up Megatron. Nice going.

    9. Re:More hair-brained ideas for "Global Warming" by Joce640k · · Score: 4, Insightful

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

      --
      No sig today...
    10. Re:More hair-brained ideas for "Global Warming" by tmosley · · Score: 3, Funny

      Strange how you can say anything on the internet and claim that it's true.

      Incidentally, I dropped an apple out of my window yesterday and it fell up! True story.

    11. Re:More hair-brained ideas for "Global Warming" by interactive_civilian · · Score: 3, Informative

      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.

      --
      "Empathise with stupidity, and you're halfway to thinking like an idiot." - Iain M. Banks
    12. Re:More hair-brained ideas for "Global Warming" by xaxa · · Score: 4, Interesting

      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.

    13. Re:More hair-brained ideas for "Global Warming" by Chris+Burke · · Score: 3, Interesting

      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?

      --

      The enemies of Democracy are
    14. Re:More hair-brained ideas for "Global Warming" by bkr1_2k · · Score: 3, Informative

      I'm going to go out on a limb here and suggest that the "in your face" refers to dental fillings. Any of us that have silver fillings have a fair bit of mercury in our mouths with little or no harm (depending upon whom you believe.) Unless of course you were born in the 80s and your dentist never used amalgam fillings.

      --
      "Growing old is inevitable; growing up is optional."
    15. Re:More hair-brained ideas for "Global Warming" by Chris+Burke · · Score: 3, Informative

      Exactly. ~5g per amalgam filling, versus ~5mg on the top-end for a CFL with "modern" ones down to 1-1.5mg.

      --

      The enemies of Democracy are
    16. Re:More hair-brained ideas for "Global Warming" by syphax · · Score: 5, Interesting

      Finally, my M.S. on the deep-ocean sequestration of carbon dioxide becomes relevant!

      CO2 is a supercritical liquid at depth, denser than water. Here's the stuff at 3300 meters (courtesy of MBARI)

      Here's your phase diagram.

      Here's some pictures that show CO2 at depth.

      Once at depth, the CO2 will slowly dissolve into the seawater, lowering the pH. Of course, we're doing this at the ocean surface as-is, so one can make the argument that it's less bad to acidify the deep ocean slowly vs. surface waters quickly.

      If you drop dry ice overboard, a goodly amount of it will dissolve before reaching bottom. There's research on this; I leave finding the reference as an exercise.

      --
      Simple Unexpected Concrete Credible Emotional Stories
    17. Re:More hair-brained ideas for "Global Warming" by Hooded+One · · Score: 3, Informative

      http://www.kqed.org/quest/blog/2009/06/12/how-toxic-is-a-busted-compact-florescent-bulb/

      The startling conclusion of the paper is that in a worse case scenario--you break a CFL in a closed, unventilated room; you vacuum the carpet, throwing mercury into the air; you set the vacuum in a corner; and then sit in the room breathing for eight hours--the amount of mercury exposure is about equivalent to the exposure you'd get from eating a can of Albacore tuna.

    18. Re:More hair-brained ideas for "Global Warming" by moosesocks · · Score: 3, Informative

      Also don't connect them to dimmer switches (even if you leave the dimmers at 100% all the time)

      Many dimmers designed for incandescents work by rapidly turning the light on and off. This is a very bad thing for inductive loads such as fluorescent starter coils, and will destroy the device in no time flat.

      But, yeah... avoiding the cheap ones seems to work pretty well. I'm sure there are also name-brands that are also crap, and cheap ones that are good, so I suppose you're best off switching brands until you find one that works well for you.

      --
      -- If you try to fail and succeed, which have you done? - Uli's moose
  2. Re:Trees by MrKaos · · Score: 5, Funny

    Is there something wrong with real trees?

    Yeah, it's realy, really, really, really, old technology.

    --
    My ism, it's full of beliefs.
  3. Re:How about 'non synth'? by FooAtWFU · · Score: 3, Insightful
    They need water. (Hello California.) They need sunlight. You need a place to put them. They may be mildly sensitive to environmental shock when you're putting them up. They're somewhat low-density. The roots can damage structures in the vicinity. After several decades they die, and if you don't do something with the carbon they sequestered in the wood it'll make its way back to the atmosphere.

    Still great, stuff, just not perfect.

    --
    The World Wide Web is dying. Soon, we shall have only the Internet.
  4. Unit of cost by nahgoe · · Score: 3, Funny
    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?

  5. Why not real trees? by Geoffrey.landis · · Score: 5, Insightful

    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.

    --
    http://www.geoffreylandis.com
    1. Re:Why not real trees? by Geoffrey.landis · · Score: 3, Interesting

      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.

      --
      http://www.geoffreylandis.com
    2. Re:Why not real trees? by Hythlodaeus · · Score: 4, Informative

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

      --
      For great justice.
    3. Re:Why not real trees? by drinkypoo · · Score: 4, Interesting

      If we could cover all the land area in the world with bamboo (heh) then we could sequester basically all excess carbon in 15 years or less. We can't, but anyway.

      There's plants other than trees which are applicable.

      --
      "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
    4. Re:Why not real trees? by blind+biker · · 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.

      --
      "The agriculture ministry is not in charge of Gundam" - Japanese ministry official.
  6. Re:How about 'non synth'? by value_added · · Score: 4, Interesting

    I don't know where to begin.

    Do you know how many species of trees are native to the more arid parts of California? The problem with most of Los Angeles, is exactly what you propose. A decades-long successful but misguided effort to cut down trees in order to save a few dollars in maintenance costs. Dunno about you, but the endless miles sun-bleached concrete and asphalt is hardly a hospitable environment, to say nothing of the problem with everyone needing an airconditioner to get through the summer because no one's thought to actually plant a frigging tree.

    Seriously, you have a problem with trees? I'd suggest that if everyone started planting new ones and did so for the next decade, we (and our planet) would be better off.

  7. Re:How about 'non synth'? by smoot123 · · Score: 3, Interesting
    Grow real trees, cut them down, convert to charcoal (yielding synthetic natural gas in the process), bury the charcoal to create new coal fields.

    Charcoal is very stable and won't re-enter the atmosphere for millions of years.

  8. Re:CO2 is water soluble by Noren · · Score: 3, Insightful

    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.