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ocschwar

Grow bamboo.

Harvest it.

Bury it.

That's the sort of thing we have to start thinking about.

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Burying bamboo or other biomass is not a particularly reliable or effective form of carbon sequestration. (Anywhere you bury it, it will decompose and most of the C02 removed from the atmosphere will wind up as CH4 + CO2.)

Carbon sequestration is a very active area of research, but for the most part, you're looking at injecting liquid C02 or water with a very large amount of dissolved C02 into deep reservoirs. Ideally, you want to inject it into a rock that will react with it to precipitate carbonate minerals over time, instead of dissolving what's already there.

At any rate, large-scale carbon sequestration is an interesting but difficult problem. It's been done successfully on small scales, but how do you do it on a global, carbon-neutral scale? It's surprisingly tough to figure out, and we're not putting anywhere enough focus on it. It's certainly better funded than a lot of things, but it needs more research and more funding.

Instead of trying to bury it, grow more. Increasing the total living biomass would reduce CO2.

Only for a year or a few years. Biomass doesn't really sequester that much carbon on a long-term scale.

You need to move CO2 from the atmosphere into the geosphere. Biomass can do that (e.g. hydrocarbons), but it's inefficient (a lot of it goes back to the atmosphere) and slow. Carbonate precipitation is much more permanent, and it's something we can force to happen at a high rate.

It has been a while but I thought that algae grown in raceway farms was the most efficient way to remove carbon? Love to read more on the bamboo side of it if you have links.

Yes, I've come to the same conclusion. After growing bamboo, it was my first idea, too, but algae is unbeatable for rate of growth. Here in Florida, we could grow millions of metric tons easily. The food could be food waste and sewage.

The plans I remember reading about (5 or so years ago) were about building large scale raceway ponds out in AZ, NM and that area as you had the ideal sun, cheap land, and it could be dried naturally further reducing energy consumption. I've also read a bit about them trying to use it for animal feed but I never could get the full story on that.

> animal feed

Isn't that going to release the carbon?

Before you bury it, convert it to biochar. This keeps it from rotting into methane and escaping and improves the soil requiring less water and fertilizer to grow crops.

I wonder if the carbon released by digging holes and cutting down the bamboo is greater than the carbon sequestered this way? At any rate I'd suggest not bothering to bury the bamboo, you can just pile it up somewhere.

Well, we have all sorts of schemes proposed to partly burn biomass and bury or spread the resulting charcoal. Surely raw green bamboo would hold more carbon.

Bamboo rots and emits methane.

Yeah, you'd have to bury it deep enough to prevent decomposition within a few hundred years. Holes that big are hard to do without heavy machinery which guzzle fossil fuels.

I wonder if you can sink the bamboo in the sea?

It's easy enough to secure big rocks to bamboo, but the same problem arises, how do you get tons and tons of bamboo and any required ballast out to deep water positions? Cargo ships! Which are some of the worst polluters on earth.

Why bury it when you can use it as a building material and textile?

Build large libraries with lots of paper books.

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