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Robotic 'trees' can turn CO2 into concrete

engadget.com

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Re: Robotic 'trees' can turn CO2 into concrete

#61

Post by vidarh »

chii wrote: post #19
taejo wrote: post #13

Earlier quoted context omitted.

Building houses is great, but if you're growing the trees in order to sequestrate carbon , you'd better be reasonably sure a decent proportion of the wood doesn't release it's carbon within the next fifty years. I don't live in a country where wood is a major building material, but I'm imagining that most wood that goes into building gets discarded within a few decades and ends up decomposing or being burnt.

and wood doesn't make for a building material that can go higher than a few stories.

Here's a 14 story wood-based apartment building in Norway:

https://www.youtube.com/watch?v=e5XsqauBCX4

http://treetsameie.no/

There are many other wood-based buildings higher than that being planned. The key for most of them is the use of various hybrid wood-laminates.

Re: Robotic 'trees' can turn CO2 into concrete

#62

Post by throwaway5752 »

6nf wrote: post #2

Every time one of these articles come up I wonder about the price per tonne of CO2 removed by simply growing wood and not burning it. I'm not really sure what that price is, but it seems to be around $20-$40 per tonne? Does anyone have a more accurate number?

If only they had a soft cap and let people trade credits to try to keep emissions under that cap to incentivize sequestration and efficiency innovations.

Re: Robotic 'trees' can turn CO2 into concrete

#63

Post by TangoTrotFox »

stronglikedan wrote: post #58
xupybd wrote: post #38

“Climate change is killing our planet“ I wouldn’t go that far. Sure it’s making it less hospitable for us and much of the complex life here. But life will go on without us.

I guess you're being downvoted for pedantry, because your statements are accurate.

More like sensationalism. I don't downvote, but the comment is absolutely ridiculous. Even the absolute worst case scenarios for climate change are not species ending events with current technology. And we have many decades ahead of us yet where can solve the problem with future technology yielding a negligible overall impact.

That said even the mild effects are undesirable and seeing how close we'll come to the worst case scenarios is not really a very smart experiment to be carrying out, but somebody stating climate change is going to kill off humanity is a perfect example of the horseshoe of idiocy that's affecting people as they surround themselves only with agreeable voices. It's how some people today can still try to argue that the climate isn't changing. It relies on echo chambers that all agree to ignore all facts and just go further and further off their respective deep ends.

Re: Robotic 'trees' can turn CO2 into concrete

#64

Post by throwaway5752 »

Seriously, everyone suggestions a crackpot idea for sequestering carbon should do the basic arithmetic for how much annual human emissions are (40 billion metric tons).

I like https://blogs.scientificamerican.com/life-unbounded/the-craz... for the perspective it offers: current human CO2 emissions are equivalent to the entire continent of Africa being covered in coniferous forest and burning to the ground in forest fires, every year.

If there is any way we save ourselves from this, it's from reduced emissions.

Re: Robotic 'trees' can turn CO2 into concrete

#65

Post by topkai22 »

Cthulhu_ wrote: post #39
chii wrote: post #15

Earlier quoted context omitted.

but wood burns so much more dirtier than coal, and leaves much more uncombusted remains that then have to clean. The problem is energy (or lack thereof) - and so why not solve it directly by adding ever larger sources of renewables, which eventually will becomes enough that there's no need to burn any fossil fuels!

Is that so? Even when ground fine and with enough oxygen? For local heating, I heard good things about the efficiency and cleanliness of wood pellet heaters.

Personal anecdote- i bought a house with a wood pellet stove as a primary heat source. There was smoke damage to the paint everywhere.

Re: Robotic 'trees' can turn CO2 into concrete

#66

Post by liveoneggs »

innocentfelon wrote: post #3

I wish more people realized the concrete thing is snake oil. When you make cement, you heat up natural CaCO3 -> CaO + CO2. The heat itself also requires combustion, so more CO2. Some cements have perhaps 10% CaCO3 added to their mix. It’s not so much desirable as cheap filler. What the media fails to realize is pumping CO2 into curing cement reverses the CaO reaction. In other words, every CO2 molecule you capture re…

so you're claiming this isn't a functional perpetual motion machine that (bonus) outputs useful building materials? come on

Re: Robotic 'trees' can turn CO2 into concrete

#67

Post by adwn »

thinkcontext wrote: post #28
village-idiot wrote: post #25

Earlier quoted context omitted.

You could also just bury it. That’s effectively putting coal back into the ground.

Wood is not dense enough for this to be cost effective.

You could burn it – the ash from burning a tree takes up only a fraction of the original volume.

Re: Robotic 'trees' can turn CO2 into concrete

#68

Post by tlb »

arlindohall wrote: post #50

I have a hard time taking an article seriously who uses an image of water vapor coming off nuclear cooling towers as an example of carbon emissions from energy production.

Those sort of cooling towers aren't just for nuclear power. They're the most efficient way of cooling anything, unless you're next to a river. Judging from the railway and storage around it, I think that's a coal plant.

Re: Robotic 'trees' can turn CO2 into concrete

#69

Post by stronglikedan »

TangoTrotFox wrote: post #63
stronglikedan wrote: post #58

Earlier quoted context omitted.

I guess you're being downvoted for pedantry, because your statements are accurate.

More like sensationalism. I don't downvote, but the comment is absolutely ridiculous. Even the absolute worst case scenarios for climate change are not species ending events with current technology. And we have many decades ahead of us yet where can solve the problem with future technology yielding a negligible overall impact. That said even the mild effects are undesirable and seeing how close we'll come to the wors…

You seem to have read a lot more into the parent comment than I did. I read it as a simple rebuttal to the articles opening statement saying climate change is killing the planet. While it's impossible for climate change to kill the planet, it is possible to render it too hazardous for humans if left unchecked.

Re: Robotic 'trees' can turn CO2 into concrete

#70

Post by KirinDave »

So, this $600/ton plant sits on top of... an incinerator. So uh, they're literally starting a fire for the sole purpose of capturing SOME of the carbon and shuffling it off to... be released into the atmosphere again elsewhere in greenhouses which will not capture it.

Ugh. 𐑜𐑸𐑚𐑩𐑡 𐑐𐑰𐑐𐑳𐑤.

Why do people like this take the future of our species for granted? This isn't funny.

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