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Comment by adrianN

12 hours ago

It’s difficult to scale this to the levels we would need to make a difference.

Yes, agree. But I'm not sure direct air capture is more scalable than trees. Yes trees need to be moved, but at least they grow by themselves.

  • IMO DAC promises are either wishful thinking or a deliberate attempt to sabotage more aggressive climate policies.

Depending on the tree, freshly cut wood can have anywhere from 1:3 to 2:1 ratio of water to actual wood fiber.

So, unless we want to remove a massive amount of fresh water from the ecosystem, we also need to invest energy in drying out the wood well below natural humidity levels (transport to a desert maybe?) on top of electrifying what is currently a diesel and gas heavy industry (cutting and transporting logs with heavy machinery).

There's definitely lower hanging fruit for getting C02 out of the cycle.

  • Dumping wet wood--even very, very wet wood in a lake and sinking it to the bottom does not "remove a massive amount of fresh water from the ecosystem". It does not remove any fresh water from the ecosystem.

    • Sinking wood into a lake won't remove the carbon unless you have a very deep lake, and you'd need many, many of them to have any impact on the CO2 levels whatsoever. The scale of wood that would need to be harvested is far beyond dropping some logs in a lake.

      They need to go into a deep enough pit where the methane produced from anerobic breakdown won't reach the atmosphere.

      The conditions that created the lignite coal and peat simply aren't that easily reproducible, especially with large volume of wood (rather than ferns over thousands and millions of years).

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The more likely candidate is mineral based, because yes trees are hard to scale this way.