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This is wrong, or perhaps I misundertand.
Entropy is a different concept from economic viability.
The rule of non-decreasing entropy applies to closed systems.
A carbon capture system running on solar energy on Earth (note: wind energy is converted solar energy) is not a closed system from the Earth perspective - its energy arrives from outside. It can decrease entropy on Earth. Whether it’s economically viable - totally different issue.
…and I don’t think the Sun gets any worse from us capturing some rays.
Its that using an extra step in the process (producing energy + CO2, then using energy to remove CO2) is going to increase entropy more than not producing CO2 in the first place.
Economic viability is separate and sometimes related to things like this.
Its irrelevant to the economy (in the short term at least) whether a process is efficient in terms of energy or resources. What is relevant is whether or not something can be done for either small sums of money, or sold for profits. More likely both in a capitalist style economy.
Note that it does happen in some cases that using less energy/resources is more profitable, but the driving force, again in a capitalist style economy, is the profit.
Also, I don’t think entropy has anything to do with carbon in the atmosphere. I thought it had to do with the size of the energy packets.
That’s essentially how many gases are made from mixtures, like notrogen or oxygen. Showing this as something new tells a lot about author’s uderstanding. Carbon capture is not about making entirely new tech, it’s optimization, and that’s where startups suck at everything except for getting and then wasting cash.
I don’t question the working principles of DAC, or as you mention separating gasses. It’s just that burning fossil fuels for energy would make no sense if you had to use most, if not all of that energy on DAC. And if you want to use low-carbon energy to power carbon capture, why not use it directly to replace fossil fuels? It seems to me that to reduce net emissions it’s most efficient not to emit it in the first place.
That’s why you power the thing with renewables. We have to switch to green energy; that’s a given. But the point of DAC is we’ve already so thoroughly fucked up the environment that we have to also go further and start cleaning up our mess. Just switching to all solar power generation and electric cars would eventually work, but it would take hundreds of years at least for atmospheric CO2 to go back to normal.
Because stationary energy generation is the easiest thing to decarbonize, while other sources are much more difficult. Also some carbon sources are so disperse to practically track down. You going to hunt down every person using a diesel generator in Subsaharan Africa, go to their rural villages, and take their generator from them? Maybe, or it might be easier to just set up one big nuclear powered DACC plant. Then you don’t have to deal with the practical and political nightmare of hunting down millions of low intensity carbon sources among the poorest people on the planet. Just let the poor village keep its diesel generator til they’re ready to switch to solar. You don’t have to go in and start taking stuff from poor people. There are lots of examples of this, low intensity sources that add up in aggregate but would be a political nightmare to try and stop. DACC shines for this.
But, as far as I remember, major contributor to carbon emissions are not poor villages, but jet sets and their factories in poor villages exploiting the work of poor villagers who have no say about their air quality lest they lose their jobs like they lost their means to sustain themselves from farming. Indeed, just not flying for fun and not selling the oil and coal that do not really belong to them would be so much more technological than trying to get grants for things they do not understand (and waste them traveling the world on planes telling everyone they should invest in it too only to then burn the rest in taxes used to support oilgascoal industry directly or not). When you show perpetum mobile here it is totally relevant - that’s how greenwashing works in terms of economy on every level, no matter what technology is being praised.
Yes but no. The two actual uses of carbon capture is to remove the co2 from the air before it would happen naturally and the other is making fuel sustainable for retro or novelty vehicles. You dont have to stop selling gas cars if all the fuel they use is made with carbon capture. This makes the fuel more expensive but more sustainable. Once you have driven a 911 or skyline you will understand why someone would want to drive a gas car ;) Also, technically you are going from a higher energy fuel to lower energy so as long as you can do something with the co2 it abides by thermodynamics but the problems arise when you consider real world losses.
TLDR: carbon capture is a technology we should use after we stopped polluting to fix the earth.
TLDR: carbon capture is a technology we should use after we stopped polluting to fix the earth.
Yeah, it would just give people a blank check to use more fossil fuels. It is kinda like a diabetic person who acquired the disease later in life, and still not adjusting their lifestyle because drugs mitigate the effects anyhow. And the person will keep eating unhealthy food or not exercising.
Pointless. The gas should be used for things that actually need it like airlines.
Trains go choo choo. But yeah that as well. On long haul flights that cant be avoided that is an excellent use for carbon capture fuel.
Specifically it’s not trying to be an over unity machine. Energy is spent pushing air through the filter medium; energy is spent moving the filter to the CO2 extractor; energy is spent heating the filter (or whatever the extraction system is); energy is spent compressing or freezing CO2 for storage
Yeah, it’s different. I think the machine on the left is an infinite energy machine. Those will never work.
The machine on the right is a carbon capture machine which does work. But not well enough. Are fast enough to solve any of the problems that we have.
I’m fine with playing around with a carbon capture machine and seeing if we can improve it, but I would never want to rely solely on it.
I want to try a thousand solutions to the global warming problem. Including societal and government changes. Cuz you know otherwise we all die.
Most pollution comes from shipping, agriculture, and other large industries. Poor countries/people cannot contribute because they are barely getting by as is. Even if the entire middle class in wealthy countries magically switched to electric/public/bicycling, started recycling, stopped watering grass, etc. it would make no noticeable difference.
The idea that social changes at individual level can help with pollution comes directly from propaganda pushed by cunts who are actually killing our planet for profit. Fuck them. Don’t spread their lies.
I don’t. When I say social change I’m more talking about like social thinking that individuals are the problem. Sorry if that was not clear.
I mean, we already have carbon sequestration machines that are even self replicating, and require minimal, if any maitenance…
Trees and algae.
The problem isn’t a missing technology. it’s our political and economic system.
I’m all for advancing tech but nothing is going to work until we fix our behavior. We use fossil fuels because they’re profitable and allow or growth-at-all-cost economy. There’s nothing for which they’re the only option. Only a few things for which they’re the best option; the power grid and transit aren’t on that list.
Cant you just feed the CO2 from the nearest coal power plant?
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And? You want to spend even more energy on capturing it from air first?
I really think we can capitalism our way out of a capitalism caused climate crisis who’s with me and rex tillerson
Where are we putting all this CO2?
To The One Place That Hasn’t Been Corrupted By Capitalism… SPACE…
Old oil wells, preferably in high limestone areas
Your beer/soda glass.
Once we get this tech shrunk down to the size of Nitrogen generators it’s going to revolutionize the industry.
I very much prefer CO2 in my drinks, some other carbon captures get you CO and I’ve heard that’s not as good as a drink carbonator
Synthetic fuels for air planes and rockets
That would put it right back into the atmosphere, though it would reduce the amount of fossil fuels used
Perhaps do this once levels are back to pre industrial and the excess is in oil wells
Perhaps we should convert all the excess to fuel and pump it into oil wells so any successor civilisations can fuck up their climate like we have
Pumping it back into wells as oil is maybe a good idea. If civilization completely collapses back to the Stone Age humanity might never rebuild and advance into an industrial era if there are no more easily accessible fossil fuels. The rapid advancements of humanity of the last two centuries is because of fossil fuels. Of course there is a chance future humans after the apocalypse can advance without fossil fuels. But we don’t know for sure. To give them a fighting chance we have to replenish whatever we took out of the ground. Otherwise they might never advance past a medieval era.
Another idea is to bury tree logs into old mines where it can’t rot so it will fossilize into coal over centuries.
Just wait until they figure out how much carbon is captured by planting a tree.
What is this tree technology you speak of
Until the tree dies and rots or burns
Specifically replanting all the forests we cut down during the age of sail is just capturing the carbon that was released when those sailing ships rotted
If we wanted to keep the carbon captured which we captured with plants, we would have to store those plants where they are safe from rot or burn them in a (not yet invented) carbon capturing furnace
It’s not just ships. Before and after ships forests were/are cleared for farming. Net carbon sequestration of almost any forest is likely to be better than cropland and pasture - more so the old forests with well developed fungi and worms and stuff that fix and recycle some of it, not so much the timber forestry but i sustect theyre better than farms still.
Steel ships did not really even slow deforestation much - globally. Though you could argue that the sail ships enabled Europeans to bring all their various shit to the Americas - so it is maybe linked to the farming thing.
https://ourworldindata.org/world-lost-one-third-forests . FYI This graph is a bit misleading because time is warped on the vertical.
We also drained and dried out wetlands and bogs which are quite good at trapping a high amount of rotting material, also to make farmland. I’m not sure if that is counted in those stats - that is possibly more of a European overpopulation thing than a global one anyway.
I dont see how it will stop unles people start eating less, or more efficiently (I guess swap a lot of cow for cereals).
I don’t think monocultures + fertilizer + pesticides is going to be all that sustainable at keeping high yields in the long run - but we shall see about that I guess. Gene techlogy does seem to create some advances.
Decomp still sequesters carbon… where do you think all the oil came from, to begin with?
Oil came from plants before there were bacteria that can digest wood
Lol, ok.
You need to read up a bit more… that is not how we got oil…
Right. So all we need to do is deposit the wood in anoxic water and bury it.
AI will develop a reaction to turn atmospheric CO2 into electricity and oxygen and then we’ll have nothing to worry about in our future except for the constant threat of combustion.
We have such technology already, it’s just too expensive
We already have that technology it just sucks. Look up plant microbial fuel cells
That small red bulb counteracts the entropy argument because you bring energy (and quite a lot of I recall) into the system.
Would be a sad day if we no longer could reduce entropy locally under the invest of energy.
What I mean by entropy is that we burn fossil fuels (low entropy) and release CO2 into the atmosphere (high entropy), so it takes a lot more energy and effort to remove CO2 than simply not burning fossil fuels.
Clearly laws of physics work against us when we try to remove a relatively low concentration gas from a planet-wide system.
Next time you write a scientific publication, /s, make sure to have it reviewed by at least 2 Nobel Prize ! 😋
(thanks for the explanation … it was not clear at all)
Would be a sad day if we no longer could reduce entropy locally under the invest of energy.
I don’t think there’d be anyone left alive to be sad in that case…
That’s sad
The wider issue is you have to generate that energy, and you have to be able to capture more carbon than that generation released.
As I understand it doesn’t at all. This is why it’s seen as analagous to a perpetual motion machine, it’s an endless chain of power plants capturing each others carbon to no end.
You could use solar of course, but then why generate anything with fossil fuels just to capture the carbon with solar? Just use solar.
Because we still need to bring CO2 levels down even if we stop burning fossil fuel.
And then we’ll probably need to burn fossil fuel to keep them at the right level, since we are in a capitalistic society and we’re never going to be able to shutdown the CO2 collectors if they are ever built.
Just checked the numbers, for those interested.
A gas power plant produces around. 200-300kWh per tonne of CO2.
Capture costs 300-900kWh per tonne captured.
So this is basically non viable using fossil fuel as the power. If you aren’t, then storage of that power is likely a lot better.
It’s also worth noting that it is still CO2 gas. Long term containment of a gas is far harder than a liquid or solid.
If you want to capture the CO2 from fossil fuel, it feels like it’d be easier to filter it out before dumping it in the atmosphere in the first place (apart from the obvious option of just not using fossil fuel)
It would, but it takes more energy that gets produced total. You’re spending 300wKh to make 220kWh of electricity.
Is that using numbers for carbon capture from the atmosphere? Carbon capture directly on the exhaust of a fossil fuel power plant would probably be an order of magnitude more efficient. Obviously you can’t sustain everything by only using fuel combustion, but you could probably reduce to total emissions per kWh quite a bit without even looking at renewables.
So power it with solar/wind?
You could just replace the power plant with solar/wind and it would be cheaper
What power plant? We’re talking about powering a carbon capture plant. If you do that with close to zero emission power, what’s the downside?
Worst case is that they realize that the carbon capture plant is inefficient and you still have wind power.
Right but the carbon capture uses more power to capture the co2 than the power plant uses to produce it. So if you replaced said power plant with renewable energy instead of using three times as much to capture the carbon from the original plant, it would net the same result.
Essentially carbon capture makes no sense until you’re at the point that carbon capture requires less energy to capture carbon than to produce it
Who says you power that thing with fossil fuels? The real way to do that is via giant nuclear reactors or reactor complexes.
Fission power can be made cheaper per MW by just making the reactors bigger. Economies of scale, the square cube law and all that. The problem with doing this in the commercial power sector is that line losses kill you on distribution. There just aren’t enough customers within a reasonable distance to make monster 10 GW or 100 GW reactors viable, regardless of how cheap they might make energy.
But DACC is one of the few applications this might not be a problem for. Just build your monster reactors right next door to your monster DACC plants.
Yes, it works as a “plan B” (along with many other things).
Don’t loose hope. We can still win. Keep pushing for producing less CO2.
There are 3 use cases I’ve seen.
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Making fossil fuel power stations “clean”.
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CO2 recovery for long term storage.
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CO2 for industrial use.
It’s no good for the first, due to energy consumption. This is the main use I’ve seen it talked up for, as something that can be retrofitted to power plants.
It’s poor for the second, since the result is a gas (hard to store long term). We would want it as a solid or liquid product, which this doesn’t do.
The last has limited requirements. We only need so much CO2.
The only large scale use case I can see for this is as part of a carbon capture system. Capture and then react to solidify the carbon. However, plants are already extremely good at this, and can do it directly from atmospheric air, using sunlight.
The only DAC variant i could see working out is if it takes the CO2 from high-concentrated sources (such as portland cement factories) and transforms it into something practical, like liquid fuel or methane.
It could be leading to cheaper methane than from biological sources, because technological processes can have higher efficiency, and therefore lower prices.
It’s poor for the second, since the result is a gas (hard to store long term). We would want it as a solid or liquid product, which this doesn’t do.
Why wouldn’t the device include or feed a compressor to liquidize the CO2? It takes just a little over 5 atm of pressure which is trivial.
You also need to sustain 5 atm, with no leaks for years. Where is it being stored, and who’s paying for the maintenance? All it would take would be a bit of civil unrest, or corruption, and the work could be undone in mass.
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Good luck building enough capacity in nuclear power to do that. Nuclear plants tend to be a lot more expensive and take a lot longer to build than anticipated.
Literally only in the US and Europe. Remove the profit motive and don’t keep on inefficient construction companies and it’s a quick process.
Can you point out a nuclear project that was a quick process? How would removing the profit motive make it quicker?
Sure, China. You can build a nuclear power plant from dirt to operation in 6 months. Not 10 years plus infinite overages, 6 months.
If there’s not a perverse profit motive at every stage and instead people are rewarded for getting the job done and getting the job done right, you end up with high quality fast engineering.
There’s no profit motive for large scale carbon capture anyway, so big CC plants and big nuclear plants would need the same political will.
Solar and Wind are cheaper than nuclear now. The main problem is it’s not sunny and/or windy every day. A carbon capture system doesn’t need to be running 24/7 though.
If we build way more wind/solar than we use then the excess can dumped into things like this.
Sorry but the economics of nuclear just doesn’t work for everything.
One of the interesting energy capture ideas I’ve seen with Solar and wind is based on kinetic potential energy in high-rise buildings. So you build a sort of heavy weight elevator that is elevated during windy and sunny hours and then it slowly gets released and gravity driven friction generating energy.
This coupled with solar windows and it’s a pretty neat idea (not sure how viable though)
Edit: examples: https://spectrum.ieee.org/gravity-energy-storage-elevators-skyscrapers
This might work on the scale of a building to even out its own power usage throughout a day, but to make a difference on a city grid scale, you need an insane amount of height and/or weight.
Check out Pumped Water Energy Storage. It’s the same concept but uses water as the weight. Doing the math on the Ludington Pumped Storage Power Plant’s active capacity, it stores over 100 billion pounds of water.
But then the power generated by those reactors is better used to power things that burn fossil fuel in a less efficient way or to simply replace the fossil fuel powered electricity generators…
Quebec transports its electricity over more than a thousand kilometers, surely distance from nuclear reactors isn’t an issue if you build the infrastructure around it.
Only when the last carbon based power plant is close, we can see if there’s energy left to waste on that capture carbon machine.
I’m sure the AI datacenters would have a few GW to spare if we put the LLMs on pause.
You would presumably capture the carbon using excess solar and wind power, which is also the cheapest power there is, sometimes going negative
Is your capture number including the cost of liquifying the CO2 for storage?
We already have solar powered carbon sequestration systems, that require almost no maintenance over a period of a couple of hundred of years of operational life…
Trees.
Until they burn or rot and release the carbon back into the air
Also trees only grow where trees grew in the past, so growing new forests will only capture the carbon that was released when the old forest there was burnt or cut
Decomp still sequesters carbon.
Sure, burning them releases a portion back, but not most of it…
What do you think comprises ash?
If you want to capture the most of the carbon, you cook the wood in an oxygen free environment turning it to charcoal and liberating volatile components (which could be used as carbon neutral fuel to run the furnaces)
Nothing can eat charcoal, so it could be stored cheaply
Co2 is liquified before storage.
And how do you plan to keep it liquefied, on a large scale, for 100s of years? It’s currently done using pressure vessels amd chillers, that require maintenance etc.
It’s also way easier to just stop digging up coal instead of inefficiently trying to get the exhaust from burning it partially back underground.
What is the name of the contraption on the left? Looks like a perperpetual motion machine but I’d like to learn more about it.
It’s sometimes called an overbalanced wheel, an early perpetual motion device. The idea is that there’s more weights on the right side than the left side, so the wheel will turn clockwise. The weights are on rods that fall to the right as the wheel turns, so there’s always going to be more weights on the right. So the wheel turns forever. Free power woohoo!
The reality is that the balls on the left are further away from the axle. Futher from the axle = greater torque. Surprise surprise it all cancels out and the wheel eventually comes to rest.
the picture on the right isn’t demonstrating an engine. They simply use renewable energy to power the fans that suck in the air.
Doesn’t change the fact that industrial carbon capture is a scam, and most of that captured CO2 is later released back into the environment to help extract oil from old wells.
https://www.aogr.com/magazine/sneak-peek-preview/carbon-capture-boosting-oil-recovery
There are plenty of arguments to be made against direct air capture, but entropy isn’t one of them. Nobody ever claimed this is some kind of perpetuum mobile.
This is a joke.
While physically possible DAC is a waste of money and energy compared to effective measures such as constructing solar farms, batteries and power lines. Even hydrolysis may look attractive.
At the latest after decarbonization of the power grid (yes I am laughing as I write this), we will want to remove CO2 from the air which was emitted 50 years ago. Also I would like to point out that the IPCC scenarios about reducing global warming already include carbon capture. Plans to remove CO2 from energy production till 2035 already only work under the premise that we actively start removing CO2 from the atmosphere simultaneously.
That’s right. We should only do one thing, and that’s to switch away from fossil fuels. It won’t be a problem that we will still have all that CO2 warming the atmosphere and acidifying the oceans, we really shouldn’t bother trying to make that tech any better, it has clearly no use.
You fucking armchair Reddit-ass commenter.
My man, the issue is that reluctance to decarbonize may be fuelled by this. Not that it will not be necessary. The current climate predictions are quite optimistic and shit is going to shit. This means we must not hope for a wonder weapon, but do what is possible and economic today, instead of active inaction and paralysis.
This sentiment is shared with a substantial part of the CCS critical experts.
