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Defund the weather engineering programs and re-allocate that money into this. It's a no-brainer.
TL;DR: 2 DAC facilities, one in Louisiana, one in Texas hope to capture ~1million tonnes/year / facility, starting 2025/2026...

The largest currently operating one is Orca in Iceland and it can only do 4k tonnes.

Also: “The Texas project will be led by the American company Occidental and other partners, including Carbon Engineering. It could be developed to eliminate up to 30 million tons of CO2 per year, according to a statement from Occidental.”

And if anybody else was wondering:

“In 2021, U.S. greenhouse gas emissions totaled 6,340.2 million metric tons of carbon dioxide equivalents, or 5,586.0 million metric tons of carbon dioxide equivalents after accounting for sequestration from the land sector.”

https://www.epa.gov/ghgemissions/inventory-us-greenhouse-gas....

Sounds like carbon neutral would take ~200 of these things.
More like at least 20,000 or more, plus whatever emissions it takes to construct, transport and operate the plants.
The goal of these systems isn't to neutralize the planet's emissions (edit: by themselves). We need to both massively decarbonize and remove carbon from the air.

The goal of these removal systems is to clean up the last bit. That's because removing carbon from the air is very expensive. It's more efficient not to emit it in the first place.

Why not both? If we can power these things with clean energy and build hundreds of them it seems like a great addition to a carbon tax or whatever other system we can implement to change our energy system.
Both are required! (did I make it seem like it was either/or, lemme know)
Carbon Neutral requires the removal of Billions of Tonnes of emissions. That is what CARBON NEUTRAL means. Cut emissions to zero, and for "CARBON NEUTRAL" you still need to remove billions of tonnes from the atmosphere.

At least 20,000 or more, plus whatever emissions it takes to construct, transport and operate the plants.

Ah you're totally right, my bad.

Better to say "The goal of these systems isn't to neutralize the planet's emissions all by themselves"

"Each site would have carbon-sucking vacuums that could eliminate up to one million tons of carbon dioxide annually. This is equal to the yearly emissions of 445,000 gas-powered cars."

Another way to put it is, if we could instantly build 10,000 of these facilities today (which don't exist and are supposed to capture orders of magnitude more CO2 than any existing plant) and ignoring the cost/emissions from the construction and operation, and they instantly stored their ~1million tonnes of emissions, this would almost be enough to sequester ~1/3rd of last years emissions.

How’s your math work? If they sequester 1 million per year and we produce 5,600 million per year, 10,000 of these would capture nearly 2x one year of emissions, not 1/3.
I'm terrible at math, so here goes:

Global emissions of around 36+ Billion Tonnes/yr, so 10k facilities * 1Mtonnes_removed/year/facility = 10 Billion Tonnes removed /year. = < 1/3rd global emissions.

not included:

+ all the wildfire emissions

+ whatever emissions it takes to actually create 10k+ DAC facilities, and operate them forever,

Ah, global emissions. I was confused because you’d responded to the comment about US emissions. Thanks for clarifying.
By the time you add oxygen to the coal, this is about one or two trainload's worth of coal offset per year, ignoring the carbon costs of manufacturing and running it.
Meanwhile literal bleeding-edge greenhouses are pumping CO2 into these buildings.

I smell a profit coming.

Terraform Industries plans to manufacture hydrocarbons from the CO2 in the air... with water, of course, and green electricity.
The thermodynamics make so little sense but ok.
Eli5?
It takes a lot of energy to pull carbon out of the air. The energy needs to come from somewhere, but if it involves burning oil then it's going to create more mess than it cleans up.
Energy should come from solar and wind, I'd think.
These sorts of projects are typically funded by fossil fuels companies.
Yes, burning fossil fuels is really inefficient. We should stop doing that. We have better options now.

And, climate models say we need to remove 10 billion tons of carbon dioxide from the air every year in 2050. It's really inefficient but there's already too much carbon dioxide in the atmosphere.

This recent TED talk by Al Gore is worth watching [0]. This is the first time I’ve heard him speak in quite some time, and I’m not sure if the fiery anger is new, but it seems appropriate.

It’s good to see real action, but it’s only scratching the surface. And even more problematic is the industry response that this tech gives them “license to keep operating”.

https://www.ted.com/talks/al_gore_what_the_fossil_fuel_indus...

Yes it's only scratching the surface. Carbon removal needs to effectively become a $1T/year industry in the next 27 years to meet climate models. That's a top 20 industry by today's standards.
Seems like this could be done much simpler and in harmony with nature by reserving more land for forests and planting trees? Technology is not a solution to every problem.
Didn't calculations show that trees aren't fast enough to help us with this problem?
Yes, those types of things are part of the solution.

Climate models say we need to be removing about 10 billion tons per year of carbon dioxide from the air by 2050, in addition to massive decarbonization.

So we need trees, this stuff, and a lot more. A new $1T industry in the next 27 years.

One big one is weathering rocks. Some rocks need to be crushed to absorb CO2, some need to be crushed and dumped into the sea.

The advantage is that it uses technology we already have. It can also be scaled easily. And can run off cheap electricity when needed.

There's debate about that, I think it boils down to:

- How afforestation efforts are done and what the cultural and labor dynamics are. There's plenty of stories of doing things wrong in the course of carbon afforestation per earlier REDD standards ( see 'REDD alert' - https://youtu.be/FPFPUhsWMaQ )

- What kinds of risks there are in sustaining a nature-based effort, from labor to simply whether an event wipes out the forest and expected carbon storage.

- Realizing afforestation depends a lot on the biome and such and in some cases can make the climate worse - there's a lot of debate about this but this thread from Forrest Fleischman comes to mind ( https://twitter.com/ForrestFleisch1/status/13062214748025323... )

- How there's systems-theory perspectives (while possibly a bit reductionistic) arguing afforestation won't be enough to deal with carbon sequestration & storage. See https://archive.is/rNJTE which references John Sterman and En-Roads.

Theres a bigger debate around forms of conservation (e.g. 'preserving' or 'rewilding' forests a la John Muir conservation vs. a more participation with nature framework of biocultural restoration as well)

Considering that we once had significantly more forested area within just the past few generations, these risks seem overblown to me.
This system proposes removing 30 millions tons per year.

A tree captures about 20 tons of carbon dioxide per year.

So this is the equivalent to 1.5 million trees.

Trees grow at about 800 trees per acre.

This effectively matches the space of 1,875 acres, around 3 square miles.

So in a way one could think of this as opening up more land for other things.

Someone else mentioned needing to remove 10 billion tons by 2050. That is 1000 sq mi, which is size of Luxembourg. That is doable but have to do every year. My guess is that we’ll run out of good forest spots. Or climate change will kill all the trees.
I think that's the wrong comparison. Sure, 1000 sq mi is the size of Luxemberg, but the entire earth's land surface is over 57 million square miles (yes, I realize only a fraction of that is usable for tree planting). If we assume the planting density is correct, that's around 0.0000175% of surface area needed. Not much at all, proportionately speaking.
It makes me suspect that the numbers are off. I found estimate that tree absorbs 20-30kg of CO2 per year. Each cubic meter absorbs 1 ton of CO2. I can't think of any tree grows fast enough for 20 tons. I bet it was originally 20kg not 20 tons.

Which means my estimate is 1000 times small. 1 million sq mi is Argentina. Which means we can absorb some CO2 with trees but there isn't enough land for what is needed.

> I bet it was originally 20kg not 20 tons.

I think you're right. Oof, that's a lot of trees. Still worth doing IMO.

Keep in mind we can divide by 10 since each tree would absorb approximately 250 kg of CO2 over that period of time. That brings us to about 78,000 square miles or 20M hectares, which seems a lot more feasible.

Oh you're totally right, 20 kg, not 20 tons. My bad.

In a year, 1 tree removes the equivalent emissions of 2 gallons of gasoline.

Why even have trees? They seem outdated. /s
Climate models say we need to be removing about 10 billion tons per year of carbon dioxide from the air by 2050, in addition to massive decarbonization.

So we need trees, this stuff, and a lot more. A new $1T industry in the next 27 years.

I dunno. $1T buys a lot of land - if we assume the amount of forest needed to reduce 10B tons of CO2 over 10 years is 50 million acres, $1T would pay $20,000/acre. That's way more than a lot of acreage goes for that you could put trees on.

Put in that light, spending $1T on some sort of magic engineered CO2 vacuum gizmo that has yet to be fully baked, will probably break down from time to time, and won't scale particularly well seems like a bad investment. No disrespect intended, just doing the math.

Carbon removal is on track to be a $1T industry per year.

There's that much excess carbon dioxide in the air.

The scale that's needed is far beyond what trees can do.

And trees have their own complications - carbon release (fires, virus, death), measurement, and attractiveness to chop down and use for other stuff. Trees haven't (yet) been optimized as carbon removal and storage devices. They just happen to be somewhat decent at it, but with some shortcomings.

I wrote more about carbon removal in my weekly newsletter here: https://tito.co/posts/do-you-think-we-need-carbon-removal-fo...

Remember that the machines require electricity, so you have to also include the land needed by the power generation and transmission equipment. And assume that the power comes only from CO2-neutral sources (very dubious assumption). And then we remember that vacuums make a lot of noise and people don't like living near noise, whereas living next to a forest is fine, so you need land padding too.
Completely agree, need to factor it all in.
We have plenty of land today. It's just not being used particularly efficiently. Suburban development and single-family housing in particular is incredibly space-inefficient.

Also, 3 square miles is not that much at all. The USA is almost 4 million square miles in area.

edit: 20 kg of CO2, not 20 tons.

This system proposes removing 30 millions tons per year.

A tree captures about 0.02 tons of carbon dioxide per year.

So this is the equivalent to 1.5 billion trees.

Trees grow at about 800 trees per acre.

This effectively matches the space of 1.875 million acres, around 2,929 square miles.

So in a way one could think of this as opening up more land for other things.

> The Texas project will be led by the American company Occidental and other partners, including Carbon Engineering. It could be developed to eliminate up to 30 million tons of CO2 per year, according to a statement from Occidental.

Isn't it so small scale comparing to this particular world problem as to be almost irrelevant?

Yes but so is the cost TBH. E.g. the bay bridge into SF cost 6.5B.
Yes the scale today is small. But climate models say we need to be removing about 10 billion tons per year of carbon dioxide from the air by 2050, in addition to massive decarbonization. Net negative.

Therefore, it's not an "if" but a "how". We must scale our ability to remove carbon from the air.

Current emissions are like 40 billion tons. So if you built like a 1000 of them you would make a sizable dent in emissions. 1.2T might sound like a lot, but global GDP is over 100T. Spending 1.2T to keep the climate steady seems well worth it.
What is the efficiency of this vs algae based systems like brilliantplanet.com?
That's not such a bad result. $1.2bn is a small amount of money to throw down the drain, assuming we learn the lesson that DAC is a complete irrelevance to our current efforts to mitigate climate change.

This "throw money at whatever companies ask us to" phase of climate change mitigation is pretty wasteful but hopefully we will learn some hard lessons at least.

When you've spent $1.2b, you will have a whole industry around it. And that industry will have employees.

And you know how employees hate to be fired... And they will vote for anyone willing to protect their industry...

I'd like to think that state-of-the-art CO2 removal could set an appropriate level for a carbon tax.