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Efficient method to capture carbon dioxide from the atmosphere

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Re: Efficient method to capture carbon dioxide from the atmosphere

#291

Post by [deleted] »

adgjlsfhk1 wrote: post #284
rayiner wrote: post #256

Earlier quoted context omitted.

It's not cheaper when you factor in the batteries, the need for sophisticated electric grids, etc. China and India continue to build huge amounts of coal power. It's not because they're too stupid to buy the cheaper option.

it is still cheaper. In the past decade, China has gone from their electricity being from 66% coal to under 58% this year, with the amount of wind and solar climbing from 12% over the same period. Their coal usage has gone up in absolute terms, but at current rates of solar and wind expansion that will reverse itself in the next 5 years with coal plants used increasingly as peaker plants. The only reason China is bui…

[deleted]

Re: Efficient method to capture carbon dioxide from the atmosphere

#292

Post by plqbfbv »

newyankee wrote: post #279
IshKebab wrote: post #266

Earlier quoted context omitted.

Also more fundamentally it's always going to be more efficient to not produce CO2 than to unproduce it. Ok maybe in a small number of circumstances there's no other option (e.g. planes), but mostly you're far better off spending your energy making solar, wind, batteries, heat pumps, insulation etc.

In today's world there is a roadmap for a However Chinese domination, global geopolitics being changed and fossil fuel industries and countries still being extremely large and powerful make even choosing the obviously cheapest (and incidentally clean) option difficult in many parts of the world. Nonetheless, it seems much more optimistic today in 2025 than say 2015 speaking purely based on where technology stands

> However Chinese domination .. make even choosing the obviously cheapest (and incidentally clean) option difficult in many parts of the world.

In what way? China has basically dwarfed solar installations of any other country combined for the last two years, and produces so many panels and so cheap that EU and US competitors are being driven out of business.

China might be the reason we CAN make the transition actually.

Re: Efficient method to capture carbon dioxide from the atmosphere

#293

Post by Manuel_D »

8bitsrule wrote: post #290
hannob wrote: post #102

Earlier quoted context omitted.

They don't, and they can't cheat physical realities either. Plants only filter out very small amounts of CO2 from the air over relatively long timeframes. That's why crop-based biofuels require such enormous amounts of space.

'Very small'?? Depends on your perspective. "The amount of CO2 removed from the atmosphere via photosynthesis from land plants is known as Terrestrial Gross Primary Production, or GPP. It represents the largest carbon exchange between land and atmosphere on the planet. GPP is typically cited in petagrams of carbon per year. One petagram equals 1 billion metric tons, which is roughly the amount of CO2 emitted each yea…

Man-made carbon emissions amount to over 40 billion metric tons annually, according to a quick Google search. Worldwide terrestrial plant carbon exchange amounts to less than 2.5% of the CO2 humans release, if plants take in 1 billion tons per year.

From the perspective of averting climate change it is indeed very small.

Re: Efficient method to capture carbon dioxide from the atmosphere

#294

Post by Manuel_D »

saubeidl wrote: post #91
PeterHolzwarth wrote: post #84

Well, instead of repeating myself manually, I'll paste in a comment of mine here from a past discussion on carbon capture: It's easy to forget why there is a bit of a challenge to getting C02 out of the air: there's so little of it, comparatively. In order, air is, broadly, made up of the following: Nitrogen: %78.084 Oxygen: %20.946 Argon: %00.934 CO2: %00.042 The stuff is essentially beyond a rounding error - it rea…

What if one started emitting Nitrogen, Oxygen and Argon in the right proportions instead to get the mix right again?

Would that actually reduce the greenhouse effect? Intuitively, it seems analogous to putting on a less dense, but thicker blanket.

Re: Efficient method to capture carbon dioxide from the atmosphere

#295

Post by dheera »

gus_massa wrote: post #289
dheera wrote: post #245

Earlier quoted context omitted.

Random idea: What if we just sequestered it into elemental carbon pellets and let it sink to the bottom of the ocean? It should not react with the water.

One idea is to charcoal the wood, it makes it harder to decompose and is similar to pure carbon. I'm not sure if it's better to send it to the bottom of the ocean or just to a big hole on land.

The big hole on land could be dangerous if a fire ever gets there. I suppose, maybe a big hole in the middle of northern Canada might be fine

Re: Efficient method to capture carbon dioxide from the atmosphere

#296

Post by rayiner »

roughly wrote: post #273
rayiner wrote: post #235

Earlier quoted context omitted.

COVID didn’t cost anyone anything in terms of improved standard of living. Curbing emissions growth would do that. People aren’t “greedy,” but my family in Bangladesh absolutely wants to live like my family in America, or at the very least like my family in Canada. They don’t consider that “greedy” and if you tell them it is they’ll laugh at you. The country’s CO2 emissions per person have increased by a factor of 5x…

> COVID didn’t cost anyone anything in terms of improved standard of living. Curbing emissions growth would do that. We live in a horrendously inefficient way. We ship everything from half way around the world in diesel ships, trucks, and trains, we buy shitty single-use plastic items packaged and shipped in single-use plastic packaging, we replace our phones instead of our batteries, our clothing and shoes degrade w…

Forget how we live. Take the per capita CO2 output of Norway—which already generates 99% of its electricity using renewables—and somehow halve it. If the Indian subcontinent increases to that level, the added CO2 output alone will be double that of the entire EU currently.

And that’s the steady-state number. It’s impossible to believe that these countries can become twice as efficient as Norway, which already has a fully renewable grid, while building a ton of housing and infrastructure that Norway doesn’t have to build because it’s already built.

Re: Efficient method to capture carbon dioxide from the atmosphere

#297

Post by adrianN »

8bitsrule wrote: post #290
hannob wrote: post #102

Earlier quoted context omitted.

They don't, and they can't cheat physical realities either. Plants only filter out very small amounts of CO2 from the air over relatively long timeframes. That's why crop-based biofuels require such enormous amounts of space.

'Very small'?? Depends on your perspective. "The amount of CO2 removed from the atmosphere via photosynthesis from land plants is known as Terrestrial Gross Primary Production, or GPP. It represents the largest carbon exchange between land and atmosphere on the planet. GPP is typically cited in petagrams of carbon per year. One petagram equals 1 billion metric tons, which is roughly the amount of CO2 emitted each yea…

You still need to turn incredible amounts of biomass into charcoal or other stable forms of carbon to make a dent in atmospheric co2. It would take decades of hard work on gigantic scales to unburn and bury the fossil fuels we used.

Re: Efficient method to capture carbon dioxide from the atmosphere

#298

Post by mr_toad »

adrianN wrote: post #58
cjbenedikt wrote: post #28

Earlier quoted context omitted.

Take a look at "wood vault". 'Wood vaulting': A simple climate solution you’ve probably never heard of | Grist https://share.google/lS8xnMGEd1pMzlNg2 Economically not attractive but apparently very efficient in locking up CO2.

The problem with any scheme to capture and store carbon from the atmosphere is the incredible amount of carbon we've blown into the air in the last 150 years. Just look at the size of the machines we use to harvest coal. Essentially you'd need to have machines of similar size working for many decades to re-bury the carbon we extracted and burned. Who's gonna pay for that?

There’s no getting around it. If we reduce CO2 emissions to zero it’s either plants or carbon capture, and one way or another the planet will have to do something with all that carbon.

Last time it took plants millions of years, and that was before things started eating wood. I’m pretty sure that we’ll have to have a hand in the process if we want to reduce CO2 levels in timespans shorter than geological.

Re: Efficient method to capture carbon dioxide from the atmosphere

#299

Post by dalyons »

rayiner wrote: post #255
dalyons wrote: post #246

Earlier quoted context omitted.

I think they are, but more by accident. They’re going to industrialize with renewables, batteries, EVs and electric everything. It’s inevitable due to economics

They will increase emissions more slowly than European countries did at the same phase in their development, but emissions will still go up a ton compared to now. China's CO2 emissions per capita is now almost double that of France. India has gone from 0.5 tons/person in 1980 to over 2 tons/person today. They're building some renewables, but they're also building a ton of coal and gas. The EU retired 11 GW of coal in…

You can’t use trends from 1980, because cheap renewables didn’t really exist until ~2023. 86% of all power generation china added in 2025 was renewable.

Renewable and battery is now ( recently) cheaper than coal. They are not stupid, that’s what they’re going to build, not coal. they’ll follow chinas trajectory closely, delayed by a couple of years. It’s well underway in Pakistan, just google their 2025 solar boom

Re: Efficient method to capture carbon dioxide from the atmosphere

#300

Post by BurningFrog »

IshKebab wrote: post #276
BurningFrog wrote: post #272

Earlier quoted context omitted.

It's hard to put my finger on why, but that's a really weird way to frame the situation. For one thing, most of us don't control any CO₂ production we can turn off. Also, even if/when we finally produced our last CO₂ molecule, the excess CO₂ will last for many centuries, and we really should get it back to lower levels. With good capture tech, you can keep keep doing some important CO₂ producing activities. Sure, it…

> most of us don't control any CO₂ production we can turn off. Uhm what? Driving? Flying? Heating? > Sure, it seems very unfeasible with current technology, but that is bound to improve as you work on it. Improve, yes. Break the laws of thermodynamics? No. You can improve a perpetual motion machine but it's never going to be useful.

Should every car owner personally optimize the CO₂ emissions of their car?

I have definitely not argued against the laws of thermodynamics.

I'm sorry, I don't even know what you're arguing for.

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