Removing CO2 From the Air Efficiently 487
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."
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).
Re:interesting, but... (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 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 [209.85.173.104]
so these devices will suck up about 1.5 months worth of C02 emissions at a miniscule amount of the energy. awesome.
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.
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.
Re:Natural device? (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
Caution (Score:2, Interesting)
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.
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?
Scrubbing is one thing ... (Score:2, Interesting)
Re:LImestone (Score:2, Interesting)
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.
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.
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.
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.
Re:Natural device? (Score:3, Interesting)
You can always capture their carbon and tuck it away in a sealed mine.
At the office, I joke that by printing a lot you are actually helping reduce CO2 because paper comes from fast-growing trees that eat up a lot of carbon in the process. As far as you don't burn it, you are reducing your carbon footprint. If we gathered all the paper we have to print and buried it deep we would be both reducing carbon in our biosphere and offering a nice stockpile of fossil fuel for the cockroach civilization that will follow ours in a couple dozen million years.
Obviously I never did the math. And I am not even slightly interested in doing it.
Re:I have seen a number of proposals before... (Score:1, Interesting)
You bring up a very good point. And I want to know how much energy it takes to re-process the absorbing material and at that point, where does the CO2 go? If they do not re-use the absorbing material, then what expense is the material to the environment? What economic expense does the material suddenly become? Does Lime suddenly have value like Gold or Platinum when it goes into high demand?
Lets see, they kick out CO2 processing and preparing the scrubbing material. Scrubbing material is used in CO2 removal machine. Scrubbing material is used up. Scrubbing material gets cleaned?/or packed for long term storage. More material is needed or if it is cleaned, the CO2 needs to be dealt with again. If the material is cleaned, how much energy does that process take and where does the CO2 go?
In a very long cycle, this machine represents a very small and incomplete portion. I don't think they accounted for CO2 to produce the PVC chimney, the motor, the fan, scrubbing material, transport of these materials to site, etc... When all of these issues are also accounted for, then lets start talking about the machines efficiency.
Re:Is it effective? (Score:3, Interesting)
First, you point out that they can use the excess energy, which would almost be free. However, a big issue with wind power is that gusts cause spikes in the output, which is usually either dumped or the turbines are braked because you can't just dump those spikes into the grid. Depending on how this works, you could dump those spikes to the carbon capture system. I'm guessing that it's not as finicky about its power requirements as our grid is, although I could well be wrong.
Re:Natural device? (Score:3, Interesting)
One of the major problems with algae-based biofuel is a lack of easy to obtain concentrated carbon dioxide.
So desert + CO2 machine + solar panels + algae = self-powered biofuel engine
Re:Natural device? (Score:3, Interesting)
The earth can deal with a certain amount of carbon itself though, so you might not need all 450 million.
It would at least be beneficial in slowing down global warming until we have a better solution.
But you know damned well that 99% of the population is going to say: "Ok, great! We've got these CO2 filter thingies now, so the problem is solved. Now where's the keys to my Hummer?"
And the better solution is never going to come along.
Re:Scrubbing is one thing ... (Score:3, Interesting)
It doesn't actually seem like an unreasonable assumption - over long timeframes.
What was the cost of 1kWh of energy 10,000 years ago? 1000 years ago? 100 years ago?
Sure, fossil fuels have gone up in cost in the last 50 years, but that is just a recent trend. There is no reason to think that the fusion power of 2050 won't be cheaper than the coal of 1900.
It might also be more expensive, but technology in general has tended to make everything cheaper with time historically. This is just one more thing.
And unless you start doing transmutation you still have carbon to dispose of somewhere.
This sort of technology could be used to help clean up diffuse carbon emissions. Sure, smoke stacks are best cleaned up at the stack - but what about lawn mowers, volcanoes, and forest fires?
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.
Re:Cow Farts... wrong end! (Score:3, Interesting)
I agree that they're orthogonal opinions. I just happen to disagree about the "moral degeneracy" bit. While the environmental damage is nonzero, it's sort of a curveball, as your original comment was only about killing animals.
While it may not apply to you, I find it interesting that many "moral vegetarians" are in the naturalistic-fallacy camp, but animal husbandry and the human consumption of meat are hardly unnatural.
Please make any responses more clear. The phrase "massive environmental damage moral degeneracy" is tough to parse without additional words and/or punctuation.