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>take it for granted that the CO2 will stay there for 10,000 years. How do you know this? CCS isn't exactly a secret, it's regularly discussed in pop science a

>take it for granted that the CO2 will stay there for 10,000 years. How do you know this? CCS isn't exactly a secret, it's regularly discussed in pop science and mainstream news. It's also controversial among actual geologists how well the storage part works, if at all. Capturing CO2 is relatively easy. When someone makes claims like it's almost guaranteed that the carbon stays in the ground for thousands of years, that's quite the grand claim that would require extraordinary evidence. Because knowing geology, there's a lot of movement through fluids, tectonics, magmatism and all sorts of micro processes altering the chemistry of the crust.

Aachen 5y ago
We do have a bit of experience with geology, though, and it's not as black and white as you put it. It staying in the ground for x amount of time is likely the median or average value within a data set. New volcanos that throw up hidden stuff aren't a daily occurrence, but they do occur and we have an idea of how often this happens. This whole "but you can't know that because we haven't let it run the full ten thousand years yet!" sounds a lot like vaccine safety reasoning, except it seems to me that we have better insight into earth's mechanics on geological timespans than our bodies' responses across a lifetime.
- trompetenaccoun 5y ago
  Requiring evidence for claims isn't putting things black and white, it's standard practice in science. I notice you have not provided any such evidence btw. And that's just one of the problems of CCS, we've not even gotten to the inherent energy requirement issue that proponents like to dismiss by saying energy from renewables can be used which is free and doesn't cause emissions. But that isn't true, energy has some cost associated with it no matter where we source it from.
  - Aachen 5y ago
    "I'm just asking for evidence" indeed nicely demonstrates the asymmetry of time investment. Next, if I dig into the research and adequately answer the question, the next remark is that the experiment didn't run for the full ten thousand years; you don't seem to trust today's knowledge anyhow (judging by the comment above). I'm a bit done with being the one who opens up Wikipedia or digs in hard-to-get-through papers to provide evidence in response to people who are just asking questions. You can accuse me but you've not given evidence of anything yourself. You're also putting up a false argument, claiming that proponents (that includes me) are saying it's gonna use magic free energy. I've actually looked into that before to figure out if something like Climeworks pollutes more than it captures. Do you have any evidence that the CCS options we have today don't work? Either because it uses orders of magnitude more energy than claimed or because the carbon is released way sooner? (Heck, I'd be fine if it stores the carbon long enough to move the problem from 6 years* to 600 years so we have time to develop fusion or, failing that, fully renewable tech. Anything closer towards 6000, let alone 10'000 years, is pure profit.) * based on https://carbonclock.hugotiger.com/ https://carbonclock.hugotiger.com/ (but feel free to pick 2030 or 2040 or whatever you deem to be true)
    - trompetenaccoun 5y ago
      >Next, if I dig into the research and... The conditional implies it's not happened yet I take it. Would people just go on the internet and write authoritatively about things they don't know and haven't even looked up? It's by the way those who make a claim (or wish to support it) that have to provide the evidence, not the other way around. It is unlikely you'll find anyone on HN inexperienced enough in formal logic to attempt to disprove a flying teapot. So you go ahead and provide the data and demonstrate how the carbon can't come to the surface in thousands of years, which was the original claim and which so far remains completely unsubstantiated.
- zackees 5y ago
PaulHoule 5y ago
There is no doubt that saline injection on a large scale will hold CO2 for a short time. The 10,000 year time span that we'd like to hold it for is a long time. A bit pessimistically, the actual injection into a saline aquifer costs something around $20 a ton, but capturing CO2 from a power plant with an amine stripper is around $80 a ton. Direct air capture is a lot more than that. We aren't seeing many carbon capture projects, even the low hanging fruit like https://www.energy.gov/sites/prod/files/2017/10/f38/mcdonald_bioeconomy_2017.pdf https://www.energy.gov/sites/prod/files/2017/10/f38/mcdonald... which is profitable at $20 a ton is not being developed because "junk carbon credits" are available at lower prices. (I know the corn-based Ethanol at the Decatur facility is environmentally negative in a lot of ways... But put that kind of system on a sugarcane Ethanol plant in Brazil, near Sao Paulo and nowhere near the rainforest, and it would be a different story.)

Aachen 5y ago

We do have a bit of experience with geology, though, and it's not as black and white as you put it. It staying in the ground for x amount of time is likely the median or average value within a data set. New volcanos that throw up hidden stuff aren't a daily occurrence, but they do occur and we have an idea of how often this happens. This whole "but you can't know that because we haven't let it run the full ten thousand years yet!" sounds a lot like vaccine safety reasoning, except it seems to me that we have better insight into earth's mechanics on geological timespans than our bodies' responses across a lifetime.

trompetenaccoun 5y ago
Requiring evidence for claims isn't putting things black and white, it's standard practice in science. I notice you have not provided any such evidence btw. And that's just one of the problems of CCS, we've not even gotten to the inherent energy requirement issue that proponents like to dismiss by saying energy from renewables can be used which is free and doesn't cause emissions. But that isn't true, energy has some cost associated with it no matter where we source it from.
- Aachen 5y ago
  "I'm just asking for evidence" indeed nicely demonstrates the asymmetry of time investment. Next, if I dig into the research and adequately answer the question, the next remark is that the experiment didn't run for the full ten thousand years; you don't seem to trust today's knowledge anyhow (judging by the comment above). I'm a bit done with being the one who opens up Wikipedia or digs in hard-to-get-through papers to provide evidence in response to people who are just asking questions. You can accuse me but you've not given evidence of anything yourself. You're also putting up a false argument, claiming that proponents (that includes me) are saying it's gonna use magic free energy. I've actually looked into that before to figure out if something like Climeworks pollutes more than it captures. Do you have any evidence that the CCS options we have today don't work? Either because it uses orders of magnitude more energy than claimed or because the carbon is released way sooner? (Heck, I'd be fine if it stores the carbon long enough to move the problem from 6 years* to 600 years so we have time to develop fusion or, failing that, fully renewable tech. Anything closer towards 6000, let alone 10'000 years, is pure profit.) * based on https://carbonclock.hugotiger.com/ https://carbonclock.hugotiger.com/ (but feel free to pick 2030 or 2040 or whatever you deem to be true)
  - trompetenaccoun 5y ago
    >Next, if I dig into the research and... The conditional implies it's not happened yet I take it. Would people just go on the internet and write authoritatively about things they don't know and haven't even looked up? It's by the way those who make a claim (or wish to support it) that have to provide the evidence, not the other way around. It is unlikely you'll find anyone on HN inexperienced enough in formal logic to attempt to disprove a flying teapot. So you go ahead and provide the data and demonstrate how the carbon can't come to the surface in thousands of years, which was the original claim and which so far remains completely unsubstantiated.
zackees 5y ago

PaulHoule 5y ago

There is no doubt that saline injection on a large scale will hold CO2 for a short time. The 10,000 year time span that we'd like to hold it for is a long time. A bit pessimistically, the actual injection into a saline aquifer costs something around $20 a ton, but capturing CO2 from a power plant with an amine stripper is around $80 a ton. Direct air capture is a lot more than that. We aren't seeing many carbon capture projects, even the low hanging fruit like https://www.energy.gov/sites/prod/files/2017/10/f38/mcdonald_bioeconomy_2017.pdf https://www.energy.gov/sites/prod/files/2017/10/f38/mcdonald... which is profitable at $20 a ton is not being developed because "junk carbon credits" are available at lower prices. (I know the corn-based Ethanol at the Decatur facility is environmentally negative in a lot of ways... But put that kind of system on a sugarcane Ethanol plant in Brazil, near Sao Paulo and nowhere near the rainforest, and it would be a different story.)