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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."
Don't we have a device that removes CO2 from the air? I thought they were called "trees."
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
Extreme Programming - Redundant Array of Inexpensive Developers
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
> 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.
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
"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.
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.
If I mod you up, it doesn't necessarily mean I agree with what you've said, sorry.
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 you had better not use coal or oil to power this, and even with Gas produced electricity the benefit is marginal.
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 rate, such a plant would emit an estimated 17,520,000 pounds, which is the equivalent of 8,760 short tons or 7,947 metric tons of CO2.
*snip*
from : http://209.85.173.104/search?q=cache:3Lo6hNKC2UwJ:www.seen.org/pages/db/method.shtml+co2+per+kilowatt+hour+coal+powerplant&hl=en&ct=clnk&cd=1&gl=au
so these devices will suck up about 1.5 months worth of C02 emissions at a miniscule amount of the energy. awesome.
-- Sex is the antonym of pringles. Once you pop it's time to stop.
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.
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...
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.
upon the advice of my lawyer, i have no sig at this time
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.
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.
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.
Religion is what happens when nature strikes and groupthink goes wrong.
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?
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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... 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.
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.
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).
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.
They may remove CO2 from the air, but where does it end up and in what form? Very, very strange. If they do not beam the stuff to Melmac (then 100kwh per ton would be REALLY efficient) it has to be transformed into something else which then has to be stored somewhere. That is a very strange article which explains only one side of the equation. Maybe I did not read it right, maybe it is some kind of magic.
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)
Andy Warhol got it right / Everybody gets the limelight
Andy Warhol got it wrong / Fifteen minutes is too long.
We have found the excuse we need to continue polluting the air. Way to go, humanity!
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. 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.
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.
Let's stop cutting down the Amazon already, shall we?
you had me at #!
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.
Only if you plant one tree, and don't use the tree for anything else.
What about planting many more orange and apple trees? What about rubber trees?
We can use trees for more than scrubbing carbon.
According to David MacKay:
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.