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Ocean Carbon Removal: Captura's marine carbon capture explained

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Re: Ocean Carbon Removal: Captura's marine carbon capture explained

#51

Post by grues-dinner »

cmckn wrote: post #9
gmuslera wrote: post #7

What could go wrong? Something must be done, that is for sure, and this approach targets the main carbon capture engine of the planet. But at the scale it must reach to do something significant it will probably (surely?) cause unintended consequences. It's like the butterfly effect applied to complex systems, if you do something big enough for causing a change it will probably affect a lot of things, most that will b…

I had the same thought when I read: > If you want to strip out 1 gigatonne of CO2 from the ocean, you probably have to put the upper few meters of the Atlantic through your machines every year That sounds…drastic! And this seems quite hand-wavy about the risks: > a lot of environmental monitoring needs to be done to prove that marine carbon-removal strategies aren’t harming aquatic life

It's also "only" a gigatonne, out of around 40 Gt of emissions per year. It's not nothing, but a mediocre year of global economic growth will outweigh it, and outweigh twice the year after. Unless we get our species' electrical generating shit together on a war footing level of effort, which we won't, global GDP will be a proxy measurement for carbon emissions for a good while.

Re: Ocean Carbon Removal: Captura's marine carbon capture explained

#52

Post by timewizard »

aziaziazi wrote: post #39
ta988 wrote: post #6

I feel like it is missing most of the important questions. What's the impact on sea life (one sentence saying we need monitoring...) The techniques used mean that all the microorganisms, planktons, algaes will be destroyed by those processes. What is the yield of those approaches, you remove 1000 tons, but how much do you produce to make the devices, maintain and run them, the boats... What do you do with the CO2, th…

> how much do you produce to make the devices, maintain and run them, the boats Boats consume way more fuel than a layman may think. I’ve been on a ~80m / 20people crew coast guard ship for 6 weeks and did a napkin math onboard based on tank levels and refueling date. It was +1000l/person/day of diesel (can’t remember precise numbers). We were moving ~50% or the time. In addition of the motors there were many BIG gen…

[dead]

Re: Ocean Carbon Removal: Captura's marine carbon capture explained

#53

Post by Lyngbakr »

grues-dinner wrote: post #47
idontwantthis wrote: post #34

I don’t see how any approach where you have to put the CO2 somewhere is ever going to work. Artificial weathering is the only approach that I’ve ever read anything remotely convincing about.

Algae seeding and having it sink to the sea floor taking the carbon with it also seems plausibly physically-possible on the face of it since it uses the exponential growth of microorganisms in rich growth media. And it's even using the same relatively concentrated carbon source as this plan. And it's almost 100% solar powered to boot (the iron seeding ships presumably would not be).

Very little organic carbon actually reaches the seafloor, though, because it is remineralised while sinking through the water column. Then, most of the organic matter that actually does reach the seafloor is similarly remineralised rather than buried.

But say we did manage to get massive amounts of organic matter into the deep ocean, we could feasibly end up creating a so-called "dead zone" that is depleted in oxygen like we see elsewhere in the ocean, which would be detrimental to deep sea life.

Re: Ocean Carbon Removal: Captura's marine carbon capture explained

#54

Post by matthewdgreen »

retrofrost wrote: post #42

I'll be honest, why even fucking with any other kind of geo-engineering other than high altitude sulfur dioxide injection. We literally have seen a big jump in warming from problably removing the sulfuric byproducts of cargoship fuel. At its heart global warming is an issue of energy in vs energy out. Its a lot harder to remove billions of tons of co2 to increase energy out versus using a couple thousand tons of sulp…

Because (1) sulfur-dioxide injection is a short term solution that doesn’t solve the problem long term, (2) there is a huge risk of termination shock if civilization ever stops injecting it, (3) the only long term route to a stable client is to stop emitting and to remove the CO2 excess we’re adding, (4) all of this assumes that solar radiation management doesn’t have terrible unexpected effects on the climate.

We’re probably going to have to do it anyway as a Hail Mary, since we’re now seeing clouds disappear due to warming. But it’s an emergency measure and not a solution. https://www.science.org/content/article/earth-s-clouds-are-s...

Re: Ocean Carbon Removal: Captura's marine carbon capture explained

#55

Post by jvanderbot »

photochemsyn wrote: post #36
jvanderbot wrote: post #11

In my sci-fi addled mind, and massive ship would trundle over the worlds oceans extracting readily available uranium and CO2 to make synthetic fuels for all time from nuclear energy. This skips a lot of important steps that likely cannot fit on one ship, but I love the idea of it.

Costs to operate the ship would be more than the recovered uranium would generate. Meaning you wouldn't recover near enough uranium to break even on refueling the ship when it was needed. Same problem with gold (Fritz Haber famously tried this scheme thinking he could erase Germany's WWI war debts, usurious though they were, with gold from seawater). Concentration is just too low to make such processes feasible.

The synthetic fuel is what you sell. The uranium keeps you producing fuel for cheaper than O&G traditional extraction.

But you're right: Just put a off-the-shelf modular reactor on the ship, then use that power to synthesize payload fuel from CO2, and the gold, uranium, etc are just helpful extras.

Re: Ocean Carbon Removal: Captura's marine carbon capture explained

#56

Post by grues-dinner »

Lyngbakr wrote: post #53
grues-dinner wrote: post #47

Earlier quoted context omitted.

Algae seeding and having it sink to the sea floor taking the carbon with it also seems plausibly physically-possible on the face of it since it uses the exponential growth of microorganisms in rich growth media. And it's even using the same relatively concentrated carbon source as this plan. And it's almost 100% solar powered to boot (the iron seeding ships presumably would not be).

Very little organic carbon actually reaches the seafloor, though, because it is remineralised while sinking through the water column. Then, most of the organic matter that actually does reach the seafloor is similarly remineralised rather than buried. But say we did manage to get massive amounts of organic matter into the deep ocean, we could feasibly end up creating a so-called "dead zone" that is depleted in oxygen…

I didn't say it's a good idea, or even that it actually works, just that it's one of the few schemes that I could even be convinced has some hope of even presenting two-digit gigatonnes of carbon to some reaction of interest a year. Which is what you'd need to be doing in the face of 40Gt/yr emissions.

Processing millions upon millions of cubic kilometres (top 5m of the sea is a bit under 2 million) through machinery just screams science fiction or greenwashing to me, simply based on "you want how many pipes?!". Current human water use is 4000km^3/yr: so it's 500 times more than that to cycle the water once.

If we could build that much processing infrastructure, we could just build decarbonised generation capacity in the first place. IEA estimates that 150ish GW of nuclear power would displace 1Gt, or maybe 600GW of solar. That's way less than pumps and handling plants for 100 Lake Baikals per year. China installed a third of that in just solar this year.

https://www.iea.org/data-and-statistics/charts/annual-direct...

Re: Ocean Carbon Removal: Captura's marine carbon capture explained

#57

Post by c22 »

was_a_dev wrote: post #46
anakaine wrote: post #43

Earlier quoted context omitted.

That sulfur was removed to reduce acid rain, so its not without some pretty terrible side effects.

The idea (in theory being the key word) is by injecting into the stratosphere minimises acid rain production and maximises cooling requiring less SO2

Wont it just fall back down again?

Re: Ocean Carbon Removal: Captura's marine carbon capture explained

#58

Post by noxer »

caseyohara wrote: post #31
youngtaff wrote: post #12

Earlier quoted context omitted.

They’re not even removing that much CO2 either > Captura’s Port of Los Angeles pilot can remove about 100 tonnes of CO2 per year from seawater. The company’s new plant under construction in Hawaii will capture 10 times that amount—a measurement the company can definitively quantify. So 1,000 tonnes of CO2 / year?

To help quantify this further, a typical passenger car emits ~5 tonnes of CO2 per year. So we’re talking about offsetting 20-200 cars per year. https://www.epa.gov/greenvehicles/greenhouse-gas-emissions-t...

Only if you ignore the who knows how many tons of CO2 was put into the atmosphere to create the thing. In reality that thing probably need to run several years to break even.

Re: Ocean Carbon Removal: Captura's marine carbon capture explained

#59

Post by noxer »

matthewdgreen wrote: post #54
retrofrost wrote: post #42

I'll be honest, why even fucking with any other kind of geo-engineering other than high altitude sulfur dioxide injection. We literally have seen a big jump in warming from problably removing the sulfuric byproducts of cargoship fuel. At its heart global warming is an issue of energy in vs energy out. Its a lot harder to remove billions of tons of co2 to increase energy out versus using a couple thousand tons of sulp…

Because (1) sulfur-dioxide injection is a short term solution that doesn’t solve the problem long term, (2) there is a huge risk of termination shock if civilization ever stops injecting it, (3) the only long term route to a stable client is to stop emitting and to remove the CO2 excess we’re adding, (4) all of this assumes that solar radiation management doesn’t have terrible unexpected effects on the climate. We’re…

Why is the goal to get something "stable" in the first place? Climate on earth never was and never will be stable, so this should not be our goal in the first place. The goal should be to keep the change fairly slow because most living things have trouble with fast changes. That's it we don't need more than that.

Re: Ocean Carbon Removal: Captura's marine carbon capture explained

#60

Post by robomartin »

The entire carbon removal "industry" is a dangerous joke. None of the systems and proposals are able deliver anything even remotely approximating planetary-scale CO2 mitigation without side effects in a range between making things worse and killing or destroying entire ecosystems. Not to mention requiring more energy, materials and resources than the planet might be able to provide. And nobody ever answers the question about violating some of the most basic laws of physics in the process.

So long as money keeps flowing into this ridiculous industry and politicians keep using FUD to drive their voter-base, the flow of nonsensical non-solution will not stop.

It is inevitable that, at some point in the future, people will finally understand reality for what it is.

As an example, it has taken around twenty years for people to finally start understanding the scale of the energy problem we have in order to support full electrification of ground transportation. And now, with AI data centers likely doubling that requirement, this is finally leading to the --surprise!-- conclusion that nuclear power is a necessary solution. I have been brutalized here on HN in the past for daring to (years ago) bring-up the simple math related to the EV problem. Today we are at a point where the issue is starting to float to the surface. That took about twenty years. The math was the same back then. It's just that people refuse to think past what is being shoved into their heads from every angle.

The next bridge to cross is the carbon removal scam. It will take time. I get it. People will eventually understand. I just hope we don't do irreparable damage to entire ecosystems between now and then.

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