12 ms·

Scientists say we’re on the cusp of a carbon dioxide–recycling revolution

201 points by masonic 9y ago

88e282102ae2e5b 9y ago
> it’s really a matter of maybe 5 to 10 years. So...not holding my breath.
- pmontra 9y ago
  If they make estimates like us, software developers, this is likely 50 to 100 years :-) The real revolution is that we won't have to drill oil and everybody will be able to make fuel from the air anywhere in the world. The economic and political consequences will be huge. However this process doesn't seem able to reduce greenhouse gases in the air. They say the fuel they get is carbon monoxide, methane, ethylene. Methane burns like this: CH4 + 4 O2 = 2 H2O + CO2. The process to create that methane from CO2 probably starts with one molecule of CO2 because there is only one C in CH4, so we had one CO2 and we end up with one CO2. Carbon monoxide burns like 2 CO + O2 = 2 CO2. Ethylene burns like C2H4 + 3 O2 = 2 CO2 + 2 H2O. They also seem to preserve the number of total CO2 molecules around. To really reduce the CO2 in the air we should find a way to turn it into stone, something like this plant in Iceland https://qz.com/1100221/the-worlds-first-negative-emissions-plant-has-opened-in-iceland-turning-carbon-dioxide-into-stone/ https://qz.com/1100221/the-worlds-first-negative-emissions-p...
  - tehwalrus 9y ago
    > They also seem to preserve the number of total CO2 molecules around. Of course, they are chemical reactions. Did you think they would destroy atoms? The idea here is to make renewable hydrocarbons: when you burn them, they are only putting CO2 that came from the atmosphere back, not releasing new CO2 from fossil fuels. It assumes that you power this fuel-generator with renewable energy, of course.
    - pmontra 9y ago
      > destroy atoms? Obviously not, that would be far too much energetic :-) If the goal is removing CO2 the reaction should combine some C into something that doesn't burn, but that's not going to happen if the goal is creating fuel.
- tytytytytytytyt 9y ago
  We'll have safe self-driving cars and a cure for cancer then, too. And we'll regrow our teeth with stem cells.
chopin 9y ago
So, I am burning some carbo hydrates to water and carbon dioxide and then... generate carbo hydrates out of it? Mmmh, something doesn't sound right.
- notabee 9y ago
  That's right, it doesn't sound right because you're making the assumption that the energy to do this would come from non-renewable energy sources. The value of this technology is to sequester carbon or convert energy output that's variable over time from renewables to a more consistent form of energy without digging more carbon out of the ground.
sandworm101 9y ago
No. Co2 is a very low-energy chemical. Converting it into nearly anything else will take far more energy than other sources. This is possible, but not economical without massive insentives. Maybe once all the oil is truly gone will this become a thing.
- mkempe 9y ago
  Are you aware of photosynthesis? free use of plentiful energy? do you have something against the kingdom of plants?
  - eloff 9y ago
    Which requires massive amounts of energy. It's not particularly efficient.
    - ianai 9y ago
      Efficiency is great unless it’s not scalable. We need a way that reliably pulls carbon out of the atmosphere and scales. It’s even better if it’s dead easy to “deploy”. Plants are less efficient at absorbing sunlight than solar panels, but they are viable in places solar panels are not and definitely scale plenty well.
      - sandworm101 9y ago
        Plants are not efficient. They dont scale. Nor do they even trap carbon. Plants turn carbon into plant matter ... which eventually rots or otherwise breaks down and releases that carbon. Only in special places like bogs or permafrost does the carbon remain for an extended time. Plants dont turn carbon into something inert and storable like coal. Solar panels can reduce carbon emmissions, but to actually take the carbon out of the air and keep it out means converting it into something akin to coal. This takes massive power, which must in turn come from a green source.
        mkempe 9y ago
rossdavidh 9y ago
I would need to see something about how much electricity they're talking about here. I am not seeing a way to do this with less than the electricity you got from burning the fossil fuels in the first place (and inevitably, somewhat more). The only way I could see this being useful is if at some point in the future we are no longer burning fossil fuels for electricity, and we want to get the CO2 back out of the atmosphere. But, you know, turning them into living trees is not a bad way to do that, and it already exists...
- davidp 9y ago
  You're mostly right, except that trees are now understood to not be a great way to sequester carbon: They eventually grow old and die, and the carbon in them is released as they rot. Over (non-geological) time trees are net carbon neutral.
  - eloff 9y ago
    I hear that mentioned a lot. But there are some important considerations. Taking previously unforrested land and converting it to forests will sequester carbon for as long as that condition holds. Planting trees and either letting them grow into old growth forests or using them for lumber can sequester carbon for centuries. Don't underestimate the value of buying time to transition to clean energy and develop more advanced technology.
    - ianai 9y ago
      That’s my thinking as well. This problem arose on the human timeline. It must also be solved on the human timeline. The real requirement is th carbon being out of th it within the human timeline and that the sequester process be continued. Seems like a net boon to the economy that way. I know I’d love to see homes built out of wood more often, as well.
  - njarboe 9y ago
    Many tree species live for thousands of years, most for hundreds. Growing them will sequester a lot of carbon. Plus the soils in mature forest will sequester more. The amount of carbon you could sequester in a mature redwood, or fir forest is huge. In climates where these tree wont grow, oaks often will and can capture a lot of carbon and live for millennia. I would be interested on where you got the idea that trees are not a good way to sequester carbon (ref to a paper?).
throwaway5752 9y ago
For those that saying this will take energy, this is a means of storing and concentrating enormous by diffuse renewable energy resources. Of course it's highly endergonic, but that's not the point.
eloff 9y ago
How can you burn fossil fuels to produce electricity, to use to turn the combustion byproducts back into fuel at any reasonable level of efficiency? Some people here are saying the electricity doesn't matter, because it is from renewable sources - but then you could just shut down that dirty coal plant and use the renewable energy directly. Something doesn't add up here.
- a3n 9y ago
  The CO2 is already there, now. Might as well use it.
  - jcranberry 9y ago
    I think the worry is that it might cost more energy to process the CO2 than it actually produces. In which case the energy would be more of a byproduct of removing the CO2 from the atmosphere, I guess?
    - notabee 9y ago
      No, the worry is that without negative emissions, there's no realistic way to head off worst case climate change. The IPCC scenarios that have us averting disaster already assume that we're going to develop carbon sequestration technology that is beyond what we can currently do. There will inevitably be some inefficiency in the conversion, but even a fairly inefficient process that is still carbon negative is desirable.
      - mkempe 9y ago
        And what will you do when the current interglacial ends? the last one --the Eemian-- was much warmer, and it did end. Or do you believe that this particular interglacial will, somehow, never end?
        kmonsen 9y ago
        It seems like we have the technology to warm up the planet within reach already
SomewhatLikely 9y ago
How would this compare to the approaches attempting to use algae?
titojankowski 9y ago
YC’s new "Carbon Removal Technologies" RFS: https://www.ycombinator.com/rfs/#carbon https://www.ycombinator.com/rfs/#carbon Index of 82 startups and projects mining carbon from the air: http://airminers.org http://airminers.org (disclosure: airminers.org co-creator)
meganibla 9y ago
Enter climate change caused by too little carbon dioxide in the atmosphere
- TheAdamAndChe 9y ago
  Sinusoidal homeostasis around a set point is far superior to exponential growth in one direction.
  - meganibla 9y ago
    Surprisingly, I find nothing to disagree with in your strawman argument ;p
drewbuschhorn 9y ago
As a former chemist involved in the field, no, we're really not. Reading the Joule letter referenced, it's basically just cheerleading, which does need to happen every few years to keep people going. Last I was involved, all the major non-nanosurface based catalysts either had horrible separability or cycles in the 1k range. Commercial catalysts frequently have cycles in the billions. When someone cracks this nut, they'll make money hand over fist, but we're not there yet. JACS has a review article every few years on this for anyone with high school chem and an actual interest.
- lambdadmitry 9y ago
  I tried to find such a review, but failed. Can you please provide a bit more pointers?
  - ianai 9y ago
    I’m curious as well.
  - drewbuschhorn 9y ago
    "Co2 fixation" / capture is the starting keyword you want, though "coalgas" frequently turns up good fundemental work from the 80s. https://pubs.acs.org/journal/jacsat#/action/doMobileSearch?&startPage=0&searchText=Co2%20fixation https://pubs.acs.org/journal/jacsat#/action/doMobileSearch?&... For reviews specifically: https://pubs.acs.org/journal/jacsat#/action/doMobileSearch?&SeriesKey=chreay&searchText="CO2%20fixation"&content=pubs https://pubs.acs.org/journal/jacsat#/action/doMobileSearch?&... See also Royal Society: http://pubs.rsc.org/en/content/articlelanding/2014/cs/c3cs60373c#!divAbstract http://pubs.rsc.org/en/content/articlelanding/2014/cs/c3cs60... . I can try and do a better filter job if people want, I think jacs keyword matching has managed to get worse.
- neltnerb 9y ago
  Not to mention that basically all the collected data and goals are centered on flue gas with high CO2 concentrations. It's contradictory, if you have isolated fossil power and for some reason have excess renewable power co-located to convert the waste back to chemicals, then just turn off the fossil power... unless this is a load balancing play, which it is not ever going to be good for. And the original oil and coal is better for converting to chemicals anyway!
noddy1 9y ago
If this could be applied to making palm oil substitute, that might be the only thing that can stop deforestation of indonesia/borneo/PNG
coldtea 9y ago
>In terms of how close we are to industrial impact—it’s really a matter of maybe 5 to 10 years. No matter how old you are when you read that, be prepared to continue to listen that the same technology is "5 to 10 years" away for the rest of your life.

201 points by masonic 9y ago

88e282102ae2e5b 9y ago

> it’s really a matter of maybe 5 to 10 years. So...not holding my breath.

pmontra 9y ago
If they make estimates like us, software developers, this is likely 50 to 100 years :-) The real revolution is that we won't have to drill oil and everybody will be able to make fuel from the air anywhere in the world. The economic and political consequences will be huge. However this process doesn't seem able to reduce greenhouse gases in the air. They say the fuel they get is carbon monoxide, methane, ethylene. Methane burns like this: CH4 + 4 O2 = 2 H2O + CO2. The process to create that methane from CO2 probably starts with one molecule of CO2 because there is only one C in CH4, so we had one CO2 and we end up with one CO2. Carbon monoxide burns like 2 CO + O2 = 2 CO2. Ethylene burns like C2H4 + 3 O2 = 2 CO2 + 2 H2O. They also seem to preserve the number of total CO2 molecules around. To really reduce the CO2 in the air we should find a way to turn it into stone, something like this plant in Iceland https://qz.com/1100221/the-worlds-first-negative-emissions-plant-has-opened-in-iceland-turning-carbon-dioxide-into-stone/ https://qz.com/1100221/the-worlds-first-negative-emissions-p...
- tehwalrus 9y ago
  > They also seem to preserve the number of total CO2 molecules around. Of course, they are chemical reactions. Did you think they would destroy atoms? The idea here is to make renewable hydrocarbons: when you burn them, they are only putting CO2 that came from the atmosphere back, not releasing new CO2 from fossil fuels. It assumes that you power this fuel-generator with renewable energy, of course.
  - pmontra 9y ago
    > destroy atoms? Obviously not, that would be far too much energetic :-) If the goal is removing CO2 the reaction should combine some C into something that doesn't burn, but that's not going to happen if the goal is creating fuel.
tytytytytytytyt 9y ago
We'll have safe self-driving cars and a cure for cancer then, too. And we'll regrow our teeth with stem cells.

chopin 9y ago

So, I am burning some carbo hydrates to water and carbon dioxide and then... generate carbo hydrates out of it? Mmmh, something doesn't sound right.

notabee 9y ago
That's right, it doesn't sound right because you're making the assumption that the energy to do this would come from non-renewable energy sources. The value of this technology is to sequester carbon or convert energy output that's variable over time from renewables to a more consistent form of energy without digging more carbon out of the ground.

sandworm101 9y ago

No. Co2 is a very low-energy chemical. Converting it into nearly anything else will take far more energy than other sources. This is possible, but not economical without massive insentives. Maybe once all the oil is truly gone will this become a thing.

mkempe 9y ago
Are you aware of photosynthesis? free use of plentiful energy? do you have something against the kingdom of plants?
- eloff 9y ago
  Which requires massive amounts of energy. It's not particularly efficient.
  - ianai 9y ago
    Efficiency is great unless it’s not scalable. We need a way that reliably pulls carbon out of the atmosphere and scales. It’s even better if it’s dead easy to “deploy”. Plants are less efficient at absorbing sunlight than solar panels, but they are viable in places solar panels are not and definitely scale plenty well.
    - sandworm101 9y ago
      Plants are not efficient. They dont scale. Nor do they even trap carbon. Plants turn carbon into plant matter ... which eventually rots or otherwise breaks down and releases that carbon. Only in special places like bogs or permafrost does the carbon remain for an extended time. Plants dont turn carbon into something inert and storable like coal. Solar panels can reduce carbon emmissions, but to actually take the carbon out of the air and keep it out means converting it into something akin to coal. This takes massive power, which must in turn come from a green source.
      - mkempe 9y ago

rossdavidh 9y ago

I would need to see something about how much electricity they're talking about here. I am not seeing a way to do this with less than the electricity you got from burning the fossil fuels in the first place (and inevitably, somewhat more). The only way I could see this being useful is if at some point in the future we are no longer burning fossil fuels for electricity, and we want to get the CO2 back out of the atmosphere. But, you know, turning them into living trees is not a bad way to do that, and it already exists...

davidp 9y ago
You're mostly right, except that trees are now understood to not be a great way to sequester carbon: They eventually grow old and die, and the carbon in them is released as they rot. Over (non-geological) time trees are net carbon neutral.
- eloff 9y ago
  I hear that mentioned a lot. But there are some important considerations. Taking previously unforrested land and converting it to forests will sequester carbon for as long as that condition holds. Planting trees and either letting them grow into old growth forests or using them for lumber can sequester carbon for centuries. Don't underestimate the value of buying time to transition to clean energy and develop more advanced technology.
  - ianai 9y ago
    That’s my thinking as well. This problem arose on the human timeline. It must also be solved on the human timeline. The real requirement is th carbon being out of th it within the human timeline and that the sequester process be continued. Seems like a net boon to the economy that way. I know I’d love to see homes built out of wood more often, as well.
- njarboe 9y ago
  Many tree species live for thousands of years, most for hundreds. Growing them will sequester a lot of carbon. Plus the soils in mature forest will sequester more. The amount of carbon you could sequester in a mature redwood, or fir forest is huge. In climates where these tree wont grow, oaks often will and can capture a lot of carbon and live for millennia. I would be interested on where you got the idea that trees are not a good way to sequester carbon (ref to a paper?).

throwaway5752 9y ago

For those that saying this will take energy, this is a means of storing and concentrating enormous by diffuse renewable energy resources. Of course it's highly endergonic, but that's not the point.

eloff 9y ago

How can you burn fossil fuels to produce electricity, to use to turn the combustion byproducts back into fuel at any reasonable level of efficiency? Some people here are saying the electricity doesn't matter, because it is from renewable sources - but then you could just shut down that dirty coal plant and use the renewable energy directly. Something doesn't add up here.

a3n 9y ago
The CO2 is already there, now. Might as well use it.
- jcranberry 9y ago
  I think the worry is that it might cost more energy to process the CO2 than it actually produces. In which case the energy would be more of a byproduct of removing the CO2 from the atmosphere, I guess?
  - notabee 9y ago
    No, the worry is that without negative emissions, there's no realistic way to head off worst case climate change. The IPCC scenarios that have us averting disaster already assume that we're going to develop carbon sequestration technology that is beyond what we can currently do. There will inevitably be some inefficiency in the conversion, but even a fairly inefficient process that is still carbon negative is desirable.
    - mkempe 9y ago
      And what will you do when the current interglacial ends? the last one --the Eemian-- was much warmer, and it did end. Or do you believe that this particular interglacial will, somehow, never end?
      - kmonsen 9y ago
        It seems like we have the technology to warm up the planet within reach already

SomewhatLikely 9y ago

How would this compare to the approaches attempting to use algae?

titojankowski 9y ago

YC’s new "Carbon Removal Technologies" RFS: https://www.ycombinator.com/rfs/#carbon https://www.ycombinator.com/rfs/#carbon Index of 82 startups and projects mining carbon from the air: http://airminers.org http://airminers.org (disclosure: airminers.org co-creator)

meganibla 9y ago

Enter climate change caused by too little carbon dioxide in the atmosphere

TheAdamAndChe 9y ago
Sinusoidal homeostasis around a set point is far superior to exponential growth in one direction.
- meganibla 9y ago
  Surprisingly, I find nothing to disagree with in your strawman argument ;p

drewbuschhorn 9y ago

As a former chemist involved in the field, no, we're really not. Reading the Joule letter referenced, it's basically just cheerleading, which does need to happen every few years to keep people going. Last I was involved, all the major non-nanosurface based catalysts either had horrible separability or cycles in the 1k range. Commercial catalysts frequently have cycles in the billions. When someone cracks this nut, they'll make money hand over fist, but we're not there yet. JACS has a review article every few years on this for anyone with high school chem and an actual interest.

lambdadmitry 9y ago
I tried to find such a review, but failed. Can you please provide a bit more pointers?
- ianai 9y ago
  I’m curious as well.
- drewbuschhorn 9y ago
  "Co2 fixation" / capture is the starting keyword you want, though "coalgas" frequently turns up good fundemental work from the 80s. https://pubs.acs.org/journal/jacsat#/action/doMobileSearch?&startPage=0&searchText=Co2%20fixation https://pubs.acs.org/journal/jacsat#/action/doMobileSearch?&... For reviews specifically: https://pubs.acs.org/journal/jacsat#/action/doMobileSearch?&SeriesKey=chreay&searchText="CO2%20fixation"&content=pubs https://pubs.acs.org/journal/jacsat#/action/doMobileSearch?&... See also Royal Society: http://pubs.rsc.org/en/content/articlelanding/2014/cs/c3cs60373c#!divAbstract http://pubs.rsc.org/en/content/articlelanding/2014/cs/c3cs60... . I can try and do a better filter job if people want, I think jacs keyword matching has managed to get worse.
neltnerb 9y ago
Not to mention that basically all the collected data and goals are centered on flue gas with high CO2 concentrations. It's contradictory, if you have isolated fossil power and for some reason have excess renewable power co-located to convert the waste back to chemicals, then just turn off the fossil power... unless this is a load balancing play, which it is not ever going to be good for. And the original oil and coal is better for converting to chemicals anyway!

noddy1 9y ago

If this could be applied to making palm oil substitute, that might be the only thing that can stop deforestation of indonesia/borneo/PNG

coldtea 9y ago

>In terms of how close we are to industrial impact—it’s really a matter of maybe 5 to 10 years. No matter how old you are when you read that, be prepared to continue to listen that the same technology is "5 to 10 years" away for the rest of your life.