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Direct air capture: our technology to capture CO₂

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Re: Direct air capture: our technology to capture CO₂

#131

Post by fatuna »

GreedClarifies wrote: post #120
shafyy wrote: post #59

Climate scientist David Ho has a good thread on CDR: https://mastodon.world/@davidho/109511745525784891 It's hard for people to visualize removing tons or billions of tons of #carbon #dioxide (CO₂). I propose we talked about CO₂ #removal (CDR) like a #time #machine (e.g., this machine will take us back 5 minutes). For example: Q: How far back in time does planting 100 million #trees take us? A: If one mature tree tak…

We created this problem by using energy and energy is the way back out of the problem. Energy released by burning one barrel of oil: ~6 GJ. Total number of barrels consumed per year: ~100M Total energy per year: 6 * 10^17 J Solar flux on 10^17 J/s or 3 * 10^24 if we had a machine that could convert CO2 -> Carbon in some stable form, we would need to use 10^-7 of the earth's solar flux. At a very high level such a mac…

We might have the technology in 20 years, but only if people are hysterica about it being needed. If everyone thinks everything is okay and it will solve it self, nothing will happen! It's a prior to the preparedness paradox.

Re: Direct air capture: our technology to capture CO₂

#132

Post by tenthirtyam »

thx-2718 wrote: post #3

"Our plants require less land than other techniques. E.g., on a land area of 0.42 acres, our Orca plant can remove 4,000 tons of CO₂ from the air every year, which is almost 1,000 times more effective than trees. The same land would host around 220 trees with an estimated capacity of 22kg each" How much land, in solar panels for example, is required to power this? Also what's the carbon waste that this generates? Is…

Ummm, seems to me that 0.42 acres of trees would sequester a lot more that 22kg of CO2 per year. Let me guesstimate from my typical annual hedge clipping - we have a (appx) 1.5m wide hedge that is (appx) 120m long equal to (appx.) 180m^2=0.044 acres. The annual clipping produces 10 hefty bags (the big bags used to carry e.g. 1 ton of gravel or stones), so maybe a total of 300-400kg for my hedge. Multiply by ten for 0.42 acres, yields about 3000-4000kg.

Sanity check anyone?

Re: Direct air capture: our technology to capture CO₂

#133

Post by it_citizen »

shafyy wrote: post #59

Climate scientist David Ho has a good thread on CDR: https://mastodon.world/@davidho/109511745525784891 It's hard for people to visualize removing tons or billions of tons of #carbon #dioxide (CO₂). I propose we talked about CO₂ #removal (CDR) like a #time #machine (e.g., this machine will take us back 5 minutes). For example: Q: How far back in time does planting 100 million #trees take us? A: If one mature tree tak…

Yet I see carbon capture being a top pick in discussions about effective altruism and by the clean air task force.

I believe their reasoning is that for the amount of money invested, it remains one of the most efficient investment to decarbonize.

I don't know what to do with that information.

Re: Direct air capture: our technology to capture CO₂

#134

Post by GreedClarifies »

stouset wrote: post #128
GreedClarifies wrote: post #120

Earlier quoted context omitted.

We created this problem by using energy and energy is the way back out of the problem. Energy released by burning one barrel of oil: ~6 GJ. Total number of barrels consumed per year: ~100M Total energy per year: 6 * 10^17 J Solar flux on 10^17 J/s or 3 * 10^24 if we had a machine that could convert CO2 -> Carbon in some stable form, we would need to use 10^-7 of the earth's solar flux. At a very high level such a mac…

I have read this analysis several times, and near as I can tell you’re basically saying “if blowing up a stick of dynamite provides x energy, we can just use that same x energy to find all the original bits of that stick and put it back together”.

We're not talking about some kind of very complex macro object.

We're talking about converting hydrocarbons -> CO2 + water (or whatever if you care) and reversing that reaction (or similar, since we may want something more stable than hydrocarbons).

There are already machines which do this (anything that does photosynthesis). We're just going to play around the edges of making the reaction more efficient and/or the results more stable.

Re: Direct air capture: our technology to capture CO₂

#135

Post by garbagecoder »

briantakita wrote: post #119
photochemsyn wrote: post #103

Earlier quoted context omitted.

Even a complete cessation of fossil fuel use won't change the current trajectory much, it'll just mean the slope (rate of warming) doesn't get much steeper. This is due to the long lag (much of it related to slow ocean equilibration to atmospheric forcing), as well as the permafrost emissions: > "Given current rates of warming, an estimated 130-160 billion tons of permafrost carbon, could be released in the form of g…

> Humans will have to adapt to a new climate regime, by necessity. It's not going to be very pretty. Somehow, I get a sense that the governing bodies are going to cause far more harm to people than the climate change. Similar to how Mao ordered the mass killing of Sparrows in a misguided belief that since sparrows eat crops, killing sparrows will increase yields. Unfortunately, killing the sparrows meant a predator o…

>Somehow, I get a sense that the governing bodies are going to cause far more harm to people than the climate change.

That sense is called "your priors." This is a very simple, mostly linear switch on top of very very very complex systems, ie CO2 concentration. Your argument is basically "we broke it, but if we fix it it will be more broken" and there's just no evidence for that, just speculation.

As long as other bad policy decisions aren't made because of the existence of CO2 sequestration there is absolutely no reason not to use it, but it's one out of perhaps 100 major initiatives that will be required to get us back to a good level.

And by the way, if you're living in a man-made climate crisis and governments start doing bad shit (like Syria?) it's still the fault of the man-made climate crisis, at least in part.

Re: Direct air capture: our technology to capture CO₂

#136

Post by GreedClarifies »

fatuna wrote: post #131
GreedClarifies wrote: post #120

Earlier quoted context omitted.

We created this problem by using energy and energy is the way back out of the problem. Energy released by burning one barrel of oil: ~6 GJ. Total number of barrels consumed per year: ~100M Total energy per year: 6 * 10^17 J Solar flux on 10^17 J/s or 3 * 10^24 if we had a machine that could convert CO2 -> Carbon in some stable form, we would need to use 10^-7 of the earth's solar flux. At a very high level such a mac…

We might have the technology in 20 years, but only if people are hysterica about it being needed. If everyone thinks everything is okay and it will solve it self, nothing will happen! It's a prior to the preparedness paradox.

I don't think so. The technology to enable this is being worked on anyway since it is economically very valuable. Its probably the 2nd most valuable technology being worked on today.

Re: Direct air capture: our technology to capture CO₂

#137

Post by newsclues »

shafyy wrote: post #59

Climate scientist David Ho has a good thread on CDR: https://mastodon.world/@davidho/109511745525784891 It's hard for people to visualize removing tons or billions of tons of #carbon #dioxide (CO₂). I propose we talked about CO₂ #removal (CDR) like a #time #machine (e.g., this machine will take us back 5 minutes). For example: Q: How far back in time does planting 100 million #trees take us? A: If one mature tree tak…

It's like bailing water out of a boat. Doesn't matter how fast you can bail the water if you can't stop or slow the leak coming in.

Which is why world leaders flying jets to Climate Change Conferences makes no sense!

Re: Direct air capture: our technology to capture CO₂

#138

Post by silisili »

tenthirtyam wrote: post #132
thx-2718 wrote: post #3

"Our plants require less land than other techniques. E.g., on a land area of 0.42 acres, our Orca plant can remove 4,000 tons of CO₂ from the air every year, which is almost 1,000 times more effective than trees. The same land would host around 220 trees with an estimated capacity of 22kg each" How much land, in solar panels for example, is required to power this? Also what's the carbon waste that this generates? Is…

Ummm, seems to me that 0.42 acres of trees would sequester a lot more that 22kg of CO2 per year. Let me guesstimate from my typical annual hedge clipping - we have a (appx) 1.5m wide hedge that is (appx) 120m long equal to (appx.) 180m^2=0.044 acres. The annual clipping produces 10 hefty bags (the big bags used to carry e.g. 1 ton of gravel or stones), so maybe a total of 300-400kg for my hedge. Multiply by ten for 0…

Unless it was edited...that sentence says 22kg per year each. So it's 22*220.

Re: Direct air capture: our technology to capture CO₂

#139

Post by 3m »

pydry wrote: post #113
johndunne wrote: post #81

Earlier quoted context omitted.

Consider UK; 204 trees * 65 million people = 13.2 billion trees. Woodland estimates there's approx 3 billion trees in the UK now. That's over 4 fold increase in trees every year. I doubt the terrain/nature could support such a significant increase in just one year, let alone a number of years. But I like the idea of more trees. https://woodlands.co.uk/blog/woodland-economics/how-many-tre...

UK population density is 715 / sq mi. World average excluding Antarctica is 154. There are less densely populated places where more trees could be planted.

Yes but that is skewed by the South of England. There's a TON of hardly populated land in Scotland/Wales.

Re: Direct air capture: our technology to capture CO₂

#140

Post by paxys »

shafyy wrote: post #59

Climate scientist David Ho has a good thread on CDR: https://mastodon.world/@davidho/109511745525784891 It's hard for people to visualize removing tons or billions of tons of #carbon #dioxide (CO₂). I propose we talked about CO₂ #removal (CDR) like a #time #machine (e.g., this machine will take us back 5 minutes). For example: Q: How far back in time does planting 100 million #trees take us? A: If one mature tree tak…

Yup. First treat the problem then treat its symptoms.
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