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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
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.
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...
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.
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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You've still got the energy cost of disposing of the CO2, by burying it or whatever. It has to be taken out of the carbon cycle completely.
1) CO2 does cause heating of the atmosphere. Thats basic physics and is not up for debate.
2) Global warming might not be bad in the long term scheme of things but its bad for the enviroment (and ourselves) as we know it.
3) Given that current natural mechanisms can't cope with the amount of CO2 we're chucking into the atmosphere then its pretty obvious they're inadequate to the needs of clearing up our mess.
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.
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.
We have found the excuse we need to continue polluting the air. Way to go, humanity!
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 #!
How do we kill countless billions?
I mean, we kill lots of delicious cows, sure -- but you'd think the people whose business it was to sell us the delicious cow meat would be counting them.
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.