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Published online 17 December 2008 | Nature | doi:10.1038/news.2008.1319
News: Briefing
Sucking carbon out of the air
Are plans to take carbon dioxide out of the air just a pipe dream, or a cure for global warming?
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When thermal coal will reach again 200$ the total cost for tonne of coal will be ~600$. I guess solar energy is cheaper.
There is a better way. Let the mineral olivine do the sequestration. Under pressure, at high temperatures. This generates more heat, which can be used to generate electricity. Carbon capture can pay for itself or more. See http://www.geo.uu.nl/Research/Geochemistry/abstracts/O_Schuiling.html http://www.pnas.org/content/early/2008/10/31/0805794105
1) Photosynthesis. Diverting $billions/year for eco-piffle would buy a lot of zero maintenance trees with 30-50 years MTBF. 2) Power plant exhaust not air. 10% CO2 is bigger than 0.04%, 250 times bigger. 3) We have entered an era of drastic global cooling from failed appearance of the next sunspot cycle. Enjoy the Green Revolution while it persists - perhaps through 2009, perhaps not. 4) Can any Enviro-whiner calculate a closed thermodynamic cycle? Using half your energy output to entrain half your CO2 is not clever.
I think solar energy must be cheap,we should use it as much as possible,decrease fossil fuel using and planting more plants as well.Green chemitry is the best way to relieve the amount of carbon dioxide in the air,thank you for your attention.
Indeed, perhaps the simplest option is to bury CO2 underground. But let's not forget that, in so doing, with every atom of C that we dispose, we also burry two atoms of Oxygen. Wouldn't this procedure deplete our athmosphere of oxygen ? Is this that we want ?
The world's *total* energy needs can currently be met with a few tons of uranium or thorium per day (~ one terawatt-day/ton metal) and available technology, and the same for the radioactive waste products. This is a *much* smaller problem than gigatons of very dilute carbon dioxide. The first rule of holes is "stop digging" and an interesting proposal can be found at http://www.coal2nuclear.com/ As to carbon dioxide sequestration, a bioengineered algae that produces a dense, indigestible wax seems feasible with near-current technology. It is not clear that anything is going to work. There is a considerable body of scientific opinion indicating that we are either very near or have already passed the tipping point.
Sucking carbon out of the air is an attractive approach. But, the current approach actually sucks carbon dioxide, not only carbon; but also oxygen what we breathe everyday. The approach can be useful in the case of climate emergency that we have to reduce CO2 immediately. The challenging issues are expensive cost and where we store the sucked CO2. The CO2 emission from fossil fuel and natural gas burning was about 30 giga-tons in 2007, thus it would cost more than 1 trillion U.S. dollars by sucking 20% of them. Using solar and wind energy can decrease the demand of burning fossil fuel and natural gas (www.renewableenergyst.org), therefore reducing CO2 amount in the atmosphere. With 1 trillion U.S. dollars for sucking 20% of annual CO2 emission, all families in the United States could install solar energy device to meet their electricity needs, and in turn reducing carbon in the air.
This is an interesting idea. Carbon trade is popular today, which is a win-win situation between the developed and developing countries. How to make the idea of sucking carbon out of the air into practice is the core issue.
After creating particles ? of limestone (CaCO3),why not to make polystyrene nano composites or some other possible polymer nano composite for rocket fuel? a useful rocket fuel that could launch rocket from moon?
This is interesting. But, where can we get the chemicals like NaOH, or Ca(OH)2? Those chemicals are not stable in the nature. Then, we need some processes that may require energy, most likely we have to burn something to obtain those chemicals (e.g. coal -> electricity -> electrolysis of NaCl solution to obtain NaOH), and use them to suck CO2 in the air. Are we in a circle?
Burring CO2 undergound will trap the oxygen also along with it. The green houses and algal beds are the ones. the potential of this work stands on rrecycling of the raw materials used to trap CO2. All the Best
Where do we get the heat energy for the following step? The energy resource around us is heavily depended on burning coal or oil, which generates CO2. "These particles are then thrown into a kiln and heated to release the CO2 and regenerate the material needed (slaked lime or titanium dioxide) to keep the system running".
The following might be of interest on the use of highly reflective microcrystals ("micromirrors") for increasing terrestrial albedo: http://www.youtube.com/watch?v=s4B_dnIMiaA
At an optimistic estimate of ~$150/tonne, surely planting trees is cheaper? It may not have the sex appeal of fancy new technology, but it's known to work and has other benefits like preventing soil erosion.
The difficulty with planting trees is that it is not, necessarily, known to work. Planting trees in arctic Canada, for example, can decrease the area's albedo (the amount of sunlight reflected) and actually amplify warming. Forests that are susceptible to wildfires obviously put CO2 back into the atmosphere, and an individual tree that dies a natural death and rots on the forest floor will also put greenhouse gases back into the air. Preventing deforestation is surely a good idea for multiple reasons - primarily maintaining habitat for wildlife and preserving ecological domains. But planting a tonne of trees is not necessarily a cure to climate change.