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Removing CO2 From the Air Efficiently
Journal written by houbou (1097327) and posted by
kdawson
on Wed Oct 01, 2008 01:55 AM
from the install-anywhere dept.
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."
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Natural device? (Score:5, Insightful)
Don't we have a device that removes CO2 from the air? I thought they were called "trees."
Re:Natural device? (Score:5, Funny)
I suppose you eat dolphin safe tuna as well?!
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Re:Natural device? (Score:5, Funny)
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?
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Re:Natural device? (Score:5, Funny)
That's a great idea ... we could even employ people to selectively cut the trees down, and others to mill the timber, and others to make things with it. I think it's possible to come up with a viable business model where we sell people products made from converted atmospheric carbon.
I'm off to the patent office!
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Re:Natural device? (Score:5, Funny)
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Re:Natural device? (Score:4, Insightful)
Paperwork is SO 1929. Everyone does things electronically now. You can bankrupt the nation entirely over the Internet now!
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Re:Natural device? (Score:5, Funny)
I suppose you eat dolphin safe tuna as well?!
No, but I do eat tuna safe dolphines. hmmm
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Re:Natural device? (Score:5, Interesting)
Yes, but nature already has a robust way of dealing with it's own carbon sink. Having tons of liquified CO2 sitting around does not sound like a long term solution. While it's a clever technological fix, it does not solve the fundamental problem Kind of like puting ice on a febrile patient instead of giving them antibiotics to kill the infection.
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Re:Natural device? (Score:4, Insightful)
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Re:Natural device? (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)
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Re:Natural device? (Score:5, Funny)
Man! Cut it out!
It's THREE steps, not four, and you CAN'T specify the intermediate one! Jeezuz...
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Re:Natural device? (Score:5, Funny)
Just wonder how much do we have to wait for a fart capture device
Thank you, Argentina. [bbc.co.uk]
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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 /.
Cow Farts... wrong end! (Score:5, Informative)
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)
Parent
Re:Natural device? (Score:5, Funny)
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.
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Physically impossible! (Score:5, Insightful)
According to David MacKay [withouthotair.com]:
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.
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Re:Natural device? (Score:5, Interesting)
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.
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Re:Natural device? (Score:4, Interesting)
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.
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Re:Natural device? (Score:5, 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.
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Re: (Score:3, Interesting)
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
Re:Natural device? (Score:4, 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).
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Re:Natural device? (Score:5, Interesting)
They are, the only downside is that the oceans are gradually becoming acidic (carbonic acid) from all that CO2 being produced.
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Re:Natural device? (Score:5, Funny)
If apostrophes meant "ZOMGHereComesAnS", we would type "treeZOMGHereComesAnSs", but they don't, so we don't.
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Re:Natural device? (Score:5, Funny)
Hockey sticks?
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Re:Natural device? (Score:4, Informative)
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).
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Re:Natural device? (Score:4, Insightful)
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.
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Re: (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 concentratio
Re:Natural device? (Score:4, Interesting)
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.
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Re:Natural device? (Score:4, Interesting)
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.
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Re:Natural device? (Score:4, Insightful)
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.
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Is it effective? (Score:3, Insightful)
Probably Not, IMHO (Score:3, Insightful)
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.
Re:Is it effective? (Score:4, Interesting)
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).
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Mine is far more efficient (Score:3, Informative)
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]
Re:Mine is far more efficient (Score:4, Funny)
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Counterproductive (Score:5, Funny)
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.
Reference point to CO2 emissions (Score:5, Informative)
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.
Re:Reference point to CO2 emissions (Score:4, Insightful)
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.
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I have seen a number of proposals before... (Score:3, Informative)
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.
If they want to remove CO2... (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.
Space missions (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.
Storage Issue (Score:3, Insightful)
Re:Storage Issue (Score:4, Informative)
Hmm, but while you are at it you will hugely acidify the ocean. The chemicals that react with the CO2 only enter the ocean so fast.
The deep ocean trenches may be deep enough to simply liquefy the CO2 so it simply pools on the bottom. This may be more promising. Still not as good as geological storage, however.
Parent
And what do we do with the CO2? (Score:5, Interesting)
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?
Frankly, I'd rather have trees (Score:4, Insightful)
Re: (Score:3, Interesting)
*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
Re:it this (Score:5, Informative)
Only a lot more efficient. An average tree will use roughly 22kg of CO2 per year. These things are estimated to remove 20 tonnes per year per square metre, so it's in excess of 1000 times more effective. Even after you factor in the CO2 produced to provide the power needed for these things, you're still likely coming out way ahead.
Parent
Re:Natural Gas Processing Plants? (Score:4, 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.
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Re:Scrubbing is one thing ... (Score:4, Interesting)
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.
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Re:CO2 is good (Score:5, 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 [sciencemag.org]. 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.
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