7 ms·
In terms of mass, that’s not a crazy number. It’s probably unrealistic chemically, but 1500 Gizas/year is not an image that would scare me off.
by jakeinspace 3y ago
In terms of mass, that’s not a crazy number. It’s probably unrealistic chemically, but 1500 Gizas/year is not an image that would scare me off.
- tsimionescu 3y agoImagine how long it actually takes to build one structure like that, even with modern techniques. You're perhaps thinking of how long it took to build more modern mega-buildings like the Empire State Building or Burj Khalifa. But those are much lighter weight than the great pyramid (365k tonnes and 500k tonnes respectively, compared to the 6M tonnes of the great pyramid). Building even one such pyramid per year would be a huge project for a wealthy industrial state. And there aren't 1500 wealthy industrial states in the world to help with the others.
- adrianN 3y agoI would suggest we bury the carbon instead of building pyramids from it. That seems a lot simpler.
- tsimionescu 3y agoSure (and that is crucial for various reasons, mostly related to fire hazards). But for the same reasons building roads is cheaper than building tunnels, burying carbon is harder than stockpiling it on the ground. At a minimum, you have to move a similar volume of soil to the carbon you're going to bury, and then move some of it back. And of course, a volume of soil equal to a certain volume of carbon is almost certainly heavier, since carbon isn't all that dense. So yes, building 1500 great pyramids of Giza is actually a low ball estimate. The right image is burying 1500 great pyramids of Giza - which is much harder and more expensive.
- adrianN 3y agoLuckily we have technology like Bagger 288[1] to help us with that. [1] https://www.youtube.com/watch?v=azEvfD4C6ow&pp=ygUKYmFnZ2VyIDI4OA%3D%3D https://www.youtube.com/watch?v=azEvfD4C6ow&pp=ygUKYmFnZ2VyI...
- tsimionescu 3y ago...which runs on fossil fuels, probably generating about as much carbon as it can help bury.
- brazzy 3y agoNope, it's entirely electrically powered, so can be run without generating carbon emissions.
- mcny 3y agoWhich brings us to our original point, it is better if you are sincere to spend this money on electricity generation. In the US, we have over 20% of electricity coming from coal. Any money spent on anything else should first go toward pushing this down to zero.
- adrianN 3y agoI don’t think people suggest that carbon sequestration is an alternative to reducing emissions. It’s just that we have already emitted too much for net zero to be enough. We need to unburn a lot of coal to keep the planet comfortable.
- tsimionescu 3y agoRead this thread again. Plenty of people are suggesting it exactly for that purpose. Why do you think the biggest proponents and investors by far in the area are fossil fuel companies? The intended message, just like for geongnineering, is "keep burning oil, we'll figure it out another way".
- concordDance 3y agoStill not much compared to the world industrial capacity. S Bagger 288 costs $100 million and can excavate 10 great pyramids a year. Excavation capacity is not the bottleneck here.
- javajosh 3y agoBurying carbon is a great idea. Similar to the great idea of preventing cells from reproducing without limit (cancer). The important question is, in both cases: how do you do it? With carbon there is an additional question: what is the demand? This is the interface with neoliberal capitalism: what is the demand? For cancer drugs, it's obvious. For carbon sequestration, it's less obvious. Currently we require individual consumers to prefer carboon negative products. But that's clearly not sustainable. Assuming we have a technical solution, what then is the political solution?
- esarbe 3y agoInstead of burying carbon, why not just not dig it up in the first place? Prohibiting fossil fuels seems like a much simper way than trying to somehow let the market regulate that.
- concordDance 3y agoYou need to prohibit them worldwide, which requires plenty of coercion of other countries. While carbon capture can be unilateral.
- esarbe 3y ago> You need to prohibit them worldwide, which requires plenty of coercion of other countries. That's easy for economic blocks like the US and the EU. There's plenty of other regulations they have coerced other nations to follow.
- avar 3y ago> Imagine how long it actually takes to build one structure like that [...] 6M tonnes of the great pyramid. This one machine in Germany is already making the equivalent of ~15 great pyramids per year, by tons of material moved: https://en.wikipedia.org/wiki/Bagger_288 https://en.wikipedia.org/wiki/Bagger_288 Carbon capture is difficult currently, but we'd have to problem dispensing with this amount of material per year on a global scale.
- josefx 3y agoYour example runs through densely packed coal. No one would be insane enough to dig through random dirt with it in order to dig up 0.01% coal.
- dash2 3y agoBut the point of the machine was to move the carbon after it's been produced. I agree there's a separate question, how much air do we need to suck through carbon extraction machines.
- concordDance 3y agoFor context, we produce about 2000 great pyramids worth of concrete every year.
- jandrewrogers 3y agoSequestering billions of tons of carbon every year requires billions of tons of chemical feedstock that we normally produce in the thousands of tons. That industrial capacity would have to be created. Scaling up the mining operations to the necessary level alone would be tangled in politics for decades, since it implies strip-mining the planet for the raw materials. Many of the emission neutral DAC models I’ve looked at lose 10% — billions of tons — of their industrial chemistry inputs every year even assuming expansive recycling of the input components to the extent possible. The annual loss greatly exceeds current annual production for all purposes.
- jiggawatts 3y agoNot to mention the energy costs of all of that industrial activity!
- barry-cotter 3y agoPeople talk about climate change as causing a 1m rise in sea levels. Averting that kind of economic and population dislocation makes the kind of energy costs being discussed seem like pissing into the ocean.
- concordDance 3y ago1m rise is tiny cost wise compared tk the global economy, just look at the Netherlands, who have calculated[1] they'd need to spend under 0.1% of their GDP to get new barriers and flood control in place to counteract 1m sea level rise. The effects on agriculture are far more severe than sea level rise. [1] http://www.deltacommissie.com/en/advies http://www.deltacommissie.com/en/advies
- ilyt 3y agoRight but you when you can put all the industry and money into not producing that much CO2 in the first place I'd wager that's far more effective way to having less CO2 in atmosphere than trying to capture it post-factum. Or just slapping the same CO2 sequestering method at the end of industrial chain that creates CO2 rather than trying to catch it later.
- jillesvangurp 3y agoAir is only about 0.04% CO2. A kg of air is about 820 liters. To get 1kg of CO2 out of that, you need to process about 2M liters of air. Or about 2 billion liters of air for 1 tonne of CO2. Assuming you can extract all of it of course. The sad reality with carbon capture is that it's an excuse to put more carbon into the atmosphere than is actually being captured. The oil and gas companies pump billions into capturing carbon are not interested in efficiencies. They are merely interested in making many billions more on dumping more carbon in the atmosphere. If that ever gets close to what they produce, their cost will be so high that they will be out of business. The goal with this is merely delaying that moment. The cynical bit is of course that they are using lots of government subsidies to pretend to capture tiny amounts of carbon. A significant portion of the IRA (1 trillion $) has been earmarked for, once more, fattening the pockets of oil and gas industry. All the carbon capture in the world to date doesn't add up to anywhere close to more than absolutely irrelevant token amounts of carbon relative to the amount we're continuing to put into the atmosphere. This amount btw. continues to grow year on year. We've merely slowed the pace at which the increase is growing. That growth is showing signs of maybe starting to decrease very soon. We'll still be putting out a larger amount of carbon every year though. We're decades away from turning that growth into actually net removing carbon. And we'll need to keep that up for centuries before it turns around current trends in global warming. But stopping the burning of oil and gas, which is now very doable, would be a nice start. That's billions of tonnes per year of co2 that we don't have to remove from the atmosphere. Orders of magnitude more than these companies will ever capture. The best way to capture carbon is to leave it in the ground and not burn it.
- dash2 3y agoI found these numbers extremely helpful, but because I'm scientifically illiterate, I still don't really know how much 2bn liters of air is. I mean, for a comparison on roughly the same scale, how much air blows through a wind farm each day?
- xxs 3y agoThe point is that the mass of the air has to be moved through the system somehow - the energy required to pump it through would offset any capture
- lozenge 3y agoWhat about economically? Think of the huge investment required to extract fossil fuels and process them into something useful. Now imagine something similarly huge in scale, but the output product, instead of being incredibly valuable, is actually useless.
- janalsncm 3y agoCaptured carbon isn’t worthless. It represents an amount of damage that wasn’t done to the environment in the future. There’s no free lunch here. You either pay the cost now or you pay it later. Florida is already paying since their homes are quickly becoming uninsurable, and that’s not going to get better.
- david-gpu 3y agoLots of carbon have already been captured, in the form of the fossil fuels that remain underground. What we need to do is to stop releasing it into our atmosphere. Once that is largely done, we can start talking about the much more costly process of recapturing it from the atmosphere.
- lozenge 3y agoSure, carbon capture has a benefit to society. Society doesn't want to pay the bill though, which could be something like $90,000 per American. https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0081648#s6 https://journals.plos.org/plosone/article?id=10.1371/journal...