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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."
After awhile, we will be dead and won't contribute to CO2. The plants will thrive and re-balance everything out.
Truth be told, I really don't believe in trying to undo things that we have caused. We don't really know how big or small our footprint is. Let's continue to be dumb about it and when we do start dying off because of things that we do, balance will be attained.
A really big electric tree? :D
geek page at KY speaks
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
"[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?
might not be an option in highly populated areas
> 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.
don't cut it off www.mgmbill.org
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.
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.
Ignorance is curable, stupid is forever.
"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?
-- Sex is the antonym of pringles. Once you pop it's time to stop.
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.
Quantify 'cheaper' ;)
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.
Don't mind me, I am just having a huge Bob & Doug McKenzie flashback... Too much Molsons, Strange Brew, eh! Canadian Scientists heh heh, damn.
While CO2 is an important greenhouse gas, methane is going to be a bigger problem now the arctic warming is releasing it into the atmosphere.
Are there efficient ways of removing methane?
yes, lets fuck around with the atmosphere a little more.
If you mod me down, I will become more powerful than you can imagine....
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...
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.
To avoid criticism; Say nothing, Do nothing, Be nothing.
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?
... 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 not putting there in the first place?
What use is removing CO2 from the atmosfere?
There is a reaction equilibrium of forming CO2 (by burning fuels, breathing, etc) and forming O2 by plants. We should restore that equilibrium, not plunder resources at one side. Because if you plunder resources at one side, you plunder the other side too. In effect, what you REALLY do with this is removing oxygen from the atmosfere.
According to "The Science of Discworld", this was what made biosphere 2 fail. So we did the experiment, know how it ends, and now it is time to learn from it.
All we need to do is persuade plankton to go on a binge.
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?
Property is theft.
I say, let the terraforming begin!
Place these things all over the martian surface and make em solar powered!
"Freedom in the USA is not the ability to do what you want. It is the ability to stop others from doing what THEY want"
Won't CO2 scrubbers kill plant life by sucking up all the CO2 in the area? Or at least enough to harm the plants. Sure doesn't sound very eco friendly.
or stop de-forestation and actually plant more of the things ??
Removing the CO2 is hard but the hardest problem is what to do with it once you have removed it. I haven't RTFA yet but I'm guessing it's going to be the old pump it under the ground solution. That's great but if you want to store a lot of CO2 that way you need to compress it and that is going to use a lot of energy.
Personally I think a better idea would be to make charcoal and bury that. Genetically engineer a very fast growing tree, turn it into charcoal after a few years and spread it on fields or just dump it in old mines.
I used to have a better sig but it broke.
And if an electric tree falls in the forest, and there is no-one there to hear it, does it make a sound?
These 'tower units' are a convenient upgrade of the now obsoleted trees. We gotta cut those old things out and replace them with these high-tech towers.
Patents Drive Free Software as Hurricanes Drive Construction Industry
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.
I think we should try to stop CO2 from being produced in the first place.
Now, if all those folks in Washington, DC would just stop talking and hold their breath ... until I say, "Stop" ...
Schroedinger's Brexit: The UK is both in and out of the EU at the same time!
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.
...how come it's better to try to remove CO2 after it's spread out in the atmosphere, in a roughly 0.0004 dilution, than at the source of CO2, like chimneys and factories and exhausts?
Somebody has to make a tick box responce for this as well.
...
...
OK, so you captured all that CO2, you have just converted your problem to CO2 sequestration.
That is a scam and a half, it costs money to shove it underground, so calculate that. Much like oil, cheap sites for sequestration are a diminishing resource.
You wanna fix your problem ? Don't make the stuff, not create excuses to do so
These type of solutions give alibi to polluters
We have found the excuse we need to continue polluting the air. Way to go, humanity!
If (a) global warming is actually happening (b) CO2 is the cause, then there are still two things to consider:
Of course, all recent evidence points to warming having ended, and having been due to natural climate variability and/or solar cycles.
Enjoy life! This is not a dress rehearsal.
...I may be reading this wrong, but isn't their solution essentially, "Let's build a giant Ionic Breeze?"
Random Thoughts From A Diseased Mind (Not For Dummies)
I would have been interested to see what exactly happens to the CO2. Do they just compress the gas, which presumably would lead to storage problems eventually, or do they actually break it down into carbon and Oxygen? Or is the CO2 stored interstitially in the "scrubbing material"? (I had a friend in my engineering class that worked on storing hydrogen in steel bars; he said you could store more in the bar than you could in a compressed gas cylinder of the same size.)
What was once true, is no longer so
This kind of technology would be absolutely fantastic for them if they were to set up some kind of outpost on the moon or Mars. They could also probably work on it and use it for their vehicles and the ISS too, though NASA may not be involved in that for much longer.
http://www.tenjou.net/
The numbers don't make any sense.
100 kilowatt hours over one year is a constant load of about 12 watts.
Air has about 0.03% CO2. Let's round that up to 0.1% or one part per thousand.
Now comes the hard part-- how much air can a 12-watt fan force through one square meter of CO2 filter material every second? Hard to say, let's estimate ten liters for starters. That would require an efficient fan and duct and a not very restrictive filter.
Air has a density of about 1.2 g/liter, so we're processing 12g/sec of air. Of that about 12mg is CO2. Per year that's about 380kg. Not too far off a ton, but not too close either.
Now we have to figure out how much energy it took to make the filter material. To capture a ton of CO2 takes about an equal amount of caustic calcium or lithium hydroxides. Unfortunately if we include the CO2 emitted to make a ton of calcium or sodium hydroxide, that's way beyond me, but it may be more than 380kg equivalent of CO2.
You have to look at all the costs and emissions involved in the whole cycle.
Although I read (okay, skimmed) the article, it seemed very light on details. Where does all the CO2 go? The only way I could see this being even close to a solution is if the end product is carbonate rock or something similar, and even then, they'd have to bury or otherwise shield from the elements whatever the end product is. ...also, would these happen to look like small round buildings with yellow tops? Shades of SimEarth for the SNES, Batman...
~Eien no Inori wo Sasagete~ Searching for my Hatsumi...
A device to scrub methane, since it's almost 100x as efficient at holding heat (see entry for GWP) than CO2, and major non biological sources seem to be venting it in mass quantities.
Some days it's just not worth
chewing through my restraints.
The problem with carbon sequestration is that it can have geo-seismic repercussions when done on an industrial scale.
Pumping billions of tonnes of waste carbon into the ground can generate huge amounts of pressure and stress underground. It's a risky scenario without thorough in depth examination of both the target site and the current stresses beneath the surface.
The Discovery Channel ran a show on this technology... See more here. http://www.ucalgary.ca/~keith/AirCapture.html
And remove what little there is of Martian atmosphere?
I guess the next step would be to send huge quantities of white paint to Mars.
Cause if we are going to make something a dead(er) wasteland - we better make sure it is done by some standards, right?
Like.. you know... the Moon.
Mit der Dummheit kämpfen Götter selbst vergebens
we'll use a fossil-fuel powered sustem to remove CO2 from the atmosphere we polluted using....oh...wait.
Good people go to bed earlier.
communist.
All the blah-blah and nobody addressed the question of filters.
Are they magically-electrical or something?
No... They are caustic soda.
http://dsc.discovery.com/tv/project-earth/explores/carbon.html
The key ingredient in the experiment is caustic soda, which absorbs CO2 in the air. It is added at the top of the machine. About 20 gallons of the chemical were used during the test.
Team members check data results throughout the 20-hour experiment. The scrubber needs to remove more CO2 than it creates (about 20 lbs.) during the test.
Hold on...
Does that mean that the device uses 20 gallons of caustic soda, for 20 hours to create or to remove 20 lbs of CO2?
Either way... it ain't JUST 100kW of electricity.
Mit der Dummheit kämpfen Götter selbst vergebens
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.
How many kilowatts of power can be produced from the amount of coal required for 1 ton of CO2?
I foresee a small circular problem of making more CO2 than the system would ever remove.
In one square meter?
What a fool believes, he sees, no wise man has the power to reason away.
The warming was caused by the sun. Geological evidence and planetary evidence supports it. Now the current cooling is also cause by the sun.
But greenie, hippy, feel-good-don't-think types don't want to hear that, do they? No, they are on a mission to "save the planet."
Let's stop cutting down the Amazon already, shall we?
you had me at #!
What about other uses for this technology? Assuming the surface area doesn't need to be flat (didn't read TFA, of course), then could a small tube utilize this in a diver's rebreather, or (on a larger scale) to clean the air on a submarine?
Non calor sed umor est qui nobis incommodat.
Apparently, the entire world has just lost their collective minds. You do not want to remove the CO2 from the air. If you do, you will kill all plant life on Earth. As that happens, all animal life will also die.
For those that don't know it, CO2 is required for plants to live. And plants are required for animals to live. Do not remove CO2 from the air.
Seeing as oxygen causes exactly the same amount of damage to the planet as CO2, I want to know when scientists are going to come up with O2 scrubbers. I don't care what it costs--taxes and mandates are no object--just get it done!
What will the trees breathe?
Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
A disconnection between polluters and atmosphere cleaning tools breeds irresponsibility. Should the taxpayers supposed to pay to clean up industry's mess? Handle pollution at the source.
https://www.youtube.com/c/BrendaEM
First caveat: It's dumb to count transmission loss. Since this tower removes CO2 from the atmosphere, which is everywhere on our planet's surface, these scrubbers would obviously be built right by the powerplant.
Second caveat: The ideal place for these things would be a place with lots of cheap, clean power and not much demand for that power. Iceland would be perfect: They have more geothermal power than they know what to do with. They could use it to scrub the whole planet's atmosphere and collect UN money for the service.
But that's small potatoes. What I'm rather picturing is something much grander, something like giant colonies of nuclear reactors somewhere in Greenland, where they wouldn't endanger anyone, and the cooling towers would be much simpler to build because it's damn cold there already. Their sole purpose would be to scrub carbon out of our atmosphere. I think it would be great.
If it's converted to methane, that would be funny because a carbon atom in methane aggravates global warming more than a carbon atom in CO2.
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.
On Cable they the Discover Channel had a show in HD where they build a CO2 scrubber almost identical to the ones describe in the papers from the University of Calgary's David Keith that the article was about.
Discover Channel
http://dsc.discovery.com/tv/project-earth/explores/carbon.html
David Keith Home page
http://www.ucalgary.ca/~keith/CO2%20Capture%20and%20Storage.html
I don't know about the whole caustic soda CO2 sequestration seems complex. David Keith papers have the whole chemistry capture and extracting the CO2 from the working fluid to reuse them.
The whole thing is like a glorified swamp cooler, and if they were smart, they could just retrofit existing cooling towers and swamp coolers to serve dual purpose of evaporation cooling and CO2 extraction.
I had an interesting though here, which is this is the first steps of terraforming.
We could store CO2 underground when it's too hot, and expel CO2 if we start to get an ice age.
Anyhow I think at this time, methane hydrates warming up on the sea floor and releasing methane in to the atmosphere is starting to occur. Or at least we are just beginning to notice anyhow.
This could end up becoming a much larger problem then CO2 soon.
http://www.independent.co.uk/news/science/hundreds-of-methane-plumes-discovered-941456.html
I am always doing that which I can not do, in order that I may learn how to do it. - Pablo Picasso
It seems very silly to build a machine that removes carbon dioxide from the air when we have a much cheaper solar-powered alternative at our disposal: trees. Yes, trees remove carbon dioxide from the air, binding the carbon in the form of cellulose (a.k.a. "wood"). The trick is to intelligently manage these natural carbon scrubbers so that they can aid in the fight against climate change.
Obviously, the worst thing you can do with a tree is to burn it: that just releases all its hoarded carbon back into the air as carbon dioxide. Even turning the tree into furniture or toothpicks leaves open the likely possibility that it will some day be burned or left out in the open to rot (an oxidative process). You can leave the tree alone, of course, but that leads to sub-optimal results: most trees grow slowly (therefore binding carbon at a very unsatisfactory pace), and are virtually certain to eventually suffer from some mishap that results in their carbon load being returned to the air, thus undoing all the good they have done in their long lives.
So what is the solution? Bury the trees! Let's devote as much acreage as we can to raising varieties of fast-growing trees (if I recall correctly, a lodgepole pine reaches maturity in about 20 years), then cutting them down and shoving them down the nearest deep hole. Abandoned mineshafts would be both practical and ironically fitting for this purpose. The harvested areas would, of course, be immediately re-planted. Net effect? We bury a bunch of carbon; it's sort of like returning oil and coal to the ground.
Parties interested in supporting my worthy proposal may send me donations (gold, silver or other precious metals only, please). Each donation will inspire me with the sincere intention to bury a tree.
Great men are almost always bad men--Lord Acton's Corollary
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'm not a degreed botanist or bioloist, but I don't think that the mere decomposition of a dead tree by fungi and other agents actually releases much carbon back into the atmosphere; most of that carbon remains out of the atmosphere but merely changes form, right?
Actually, if you really wanna get technical about it, trees are an indirect contributor to carbon dioxide emissions while living: they are a food source for other living things, which having been thus fed and sustained will then exhale carbon dioxide as a byproduct of consuming that tree and "combusting" the energy in its tissue. In that way it might be that trees actually return as much CO2 to the environment in a year as they remove through photosynthesis.
At 7 cents per kilowatt hour, that's $140 a year per person. That's really not bad.
But if we do a good job of this, at some point we'll have a secondary problem. How do we get all that Oxygen back?
The normal way would be photosynthesis. That's going to build sugars, which would have some oxygen, a lot of hydrogen and a lot of carbon. We would then bury THAT.
But it would be much better to find a way to strip most of the oxygen away from the carbon, and leave us with something like coal. How do we do it? Let's say this is 20 years from now and we have fantastic solar energy. We have a lot of electricity, and it's cheap.
Can it be done? How?
I can imagine this script:
Futuristic society, post apocalyptic.
Plants grow slowly, food is scarce
People aren't allowed to live past 30 years old because their personal value is outweighed by the damage caused by their carbon footprint and food consumption.
Some big machine is protected by the "elders" of the society because without it the world would cease to exist.
Hero of story is age 29 about to turn 30.
Hero runs away from society chased by law enforcemnt.
Hero finds old refugees and some old guys who convinces hero that machine must be shut off.
are there any reliable and cost-effective ways to store it or dispose of it
I think we should wait until we have a space elevator and then pump it to the top, bottle it, and bring it to the moon to feed the plants. The vacuum of space should freeze it enough that we can simply rain it down on the moon and collect the bits later. No need to do landers, just transfer orbits.
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
Really, trees are just a much better idea. Lumber is better to store carbon from trees. We still have hundreds of millions of people living in cardboard and tincan shacks around the planet. I think it would be borderline socially criminal to bury trees instead of providing cheap lumber universally for construction. And properly made wooden houses can last a long time if they are a foot or better off the ground and away from termites. Heck, the US is still a young nation compared to nations in europe, and I have lived in still very good shape wooden homes built in the 1700s in New England. Very common. That's a long time to have stable and useful stored carbon. And having to use electricity for these manufactured devices when so many are still using oil lamps and such? Again, borderline socially criminal. Spend the manufacturing effort in building better solar PV and wind chargers and get them out there to people cheap, folks who don't have any power now, or just very expensive power.
And large trees left alone-the ones you don't harvest for lumber, say nut producing trees- can last hundreds of years. They could store the excess carbon at least until then, and by then maybe we will have better technical climate and energy solutions-one would hope anyway.
Anyway, for those reasons and more, I vote no on building millions of manufactured co2 suckers. Plant trees, so we can house people, provide food and fuel, help to rectify desertification, increase local water supply, provide cooling shade and cold wind blocks-trees are just spiffy. Hey, "solar powered".
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.
Do you mean 200kWh? kW is a measure of power, and kWh is a measure of energy.
Thanks!
Actually, you plant the plants (paid labor) then you uproot them and bury them to "sequester the carbon" (more paid labor).
Thousands of years later those plants have been compressed into a hard black rocky substance that can be burned.
See... coal is a renewable resource!
(not to step on the joke, but burying plants deep under ground is just as good an idea as all those other sequesterizing ideas. Bulk plant material would be easier to handle then trying to inject liquid CO2 deep into the earth or ocean. Think about it...)
Innocent people shouldn't be forced to pay for inferior software development.
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I was just going to do it myself, but my gut feel was that it was on the order of 10% or so. Thanks for the confirmation. Losing 10-15% off the top for carbon neutrality seems like a no-brainer. Hopefully the technology scales up to megaton levels reasonably well, and they have a good solution for what to do with the CO2 once it's been scrubbed (the article is thin on details).
I seem to remember that the CO2 diffuses into the ocean after that, rather than staying bound where you left it. A quick Google search returns conflicting results, though. There goes another hour of my life...
If you collect and bury CO2, you're effectively removing oxygen from the atmosphere. So a machine that does this is stupid, NO MATTER how efficient it is, because most life requires oxygen for respiration (I'm not worried about carbon sequestration because of several reasons, one of which is the ratio of 1 C atom per 2 O atoms). Trees, although they might take up more room and be less efficient in terms of volume and space than these machines, are free and give us oxygen, and look good while they do it.
Could this device be modified to remove methane instead? Methane is many times as powerful a greenhosue gas, and you could then burn it to power the device, possibly with some power left over. That would reduce global warming and provide a profit.