[gus_massa]

I agree. Plants are not very efficient (1% or 2%) but they include packaging the CO2 in a stable form. You can store the grain or wood for long periods of times.

In this case, it looks like they get CO2 as a gas. It's cheaper because you don't have to use energy to undo the burning, but it's difficult to store for a long time.

(I'm not sure if someone tried to make a fake underground bog in abandoned mine. Just fill with wood and water to keep the oxygen low and make the wood decompose slowly.)

[cjbenedikt]

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.

[adrianN]

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?

[mr_toad]

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.

[adrianN]

I agree that we’ll actively have to do something if we want to reduce carbon levels. I’m not convinced that we’ll want to reduce carbon levels badly enough to spent all that money. It’s very hard to convince voters that they’ll have to spent lots of taxes for a project that sees payoff in two or three generations at the earliest.

[dheera]

> stable form

Not really, forest fires happen and then a few hundred of years of sequestered CO2 gets released back in an instant.

Organic material with oxygen gas floating around is not stable.

Sequestering carbon into the ocean might be a better strategy. Not flammable and not subject to stupid capitalism effects around land prices.

[lefra]

The ocean has already absorbed 30% of the CO2 humanity has emitted. It causes issues: ocean acidity rises, which reduces plankton ability to grow. Plankton being the base of the ocean food chain, all ocean life gets impacted.

You'd need to find a way to sequester carbon without it leaching in the water.

https://marine.copernicus.eu/ocean-climate-portal/ocean-carb...

[dheera]

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.

[gus_massa]

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.

[dheera]

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

[gus_massa]

Yep https://en.wikipedia.org/wiki/Centralia_mine_fire