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We need to take CO2 out of the sky – an overview of climate tech

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Re: We need to take CO2 out of the sky – an overview of climate tech

#241

Post by lukifer »

sampo wrote: post #148
lukifer wrote: post #144

Earlier quoted context omitted.

This is the secret. The average citizen would actually come out ahead financially, making it a progressive tax, as opposed to the de-facto regressive taxes that have received popular opposition in other attempts. "The Largest Public Statement of Economists in History": https://clcouncil.org/economists-statement/

> The average citizen would actually come out ahead financially For a while. But if the carbon tax works and society switches to clean energy, then there is no more emissions and no more dividends pay to the citizens.

I suspect there will be always be use cases for fossil fuels; for instance, even when 99% of all cars are electric, I wouldn't want to deny auto enthusiasts muscle cars and the like, if they're willing to pay for the societal externality. The carbon tax can continue to go up to cover these cases.

Moreover, I think the same model can apply to other negative externalities (aka, Pigovian Tax [0]). But to the extent that the public will someday complain that their carbon dividend is going down: (a) I call that a good problem to have, and (b) because the collective action problem now points the other direction, there's no individual incentive to over-consume such that the dividend goes up again.

[0] https://en.wikipedia.org/wiki/Pigovian_tax

Re: We need to take CO2 out of the sky – an overview of climate tech

#242

Post by antisthenes »

BurningFrog wrote: post #189
acd wrote: post #120

We need to stop consuming like there is no tomorrow. This is driven by advertisement convincing consumers they should buy products they may not need. Secondly we need to make products which lasts a life time. I see root cause that we need to remodel the economy from market economy consumerism to a circular sustainable economy. Most current economists is saying expand expand expand, but that increases co2 levels due t…

I'm sorry, but this is nonsense. The atmospheric CO₂ rates come from burning too much fossil fuel. Not from people wanting things. If you consume and produce things in a way that doesn't release net CO₂, that is perfectly fine from a climate perspective, even if the products are meaningless artefacts of a materialistic life that will never make you happy. I understand the impulse toward a simpler, less materialistic…

> If you consume and produce things in a way that doesn't release net CO₂

So far global output of wealth and well-being is directly tied to emissions and consumption of fossil fuels. We have a 110-year long precedent for that. You could even argue it started with the Industrial Revolution, so the period is longer.

France is probably the only example of a country that came close enough to decoupling economic prosperity from CO2 production through Nuclear energy, but even they produce 5GT of CO2 per person.

It also isn't particularly evident that Nuclear is reproducible worldwide - it is very expensive, and Uranium is also a finite resource if you were to multiply its use by a factor of 10x/20x, etc. Remember, France is less than 1% of the world's population.

So decoupling prosperity from emissions is pretty much the panacea everyone wants. But it's unrealistic to hope for it and expect it to come in on our timeline. Kind of like fusion.

Re: We need to take CO2 out of the sky – an overview of climate tech

#243

Post by lopmotr »

ComputerGuru wrote: post #166
lopmotr wrote: post #149

Earlier quoted context omitted.

It's not an existential crisis. That's not what the science says. There's no evidence that climate change will make humans extinct or end civilization. If that's not what you mean by existential crisis, then don't use that word because that's what it means.

There’s plenty of evidence that a whole lot of other plants and animals will cease to exist, though.

That's just being pedantic and obviously not what the GP's post means. If it were, then walking in the garden is an existential crisis because you're bound to step on a bug and that individual will cease to exist.

Re: We need to take CO2 out of the sky – an overview of climate tech

#244

Post by labawi »

antisthenes wrote: post #242
BurningFrog wrote: post #189

Earlier quoted context omitted.

I'm sorry, but this is nonsense. The atmospheric CO₂ rates come from burning too much fossil fuel. Not from people wanting things. If you consume and produce things in a way that doesn't release net CO₂, that is perfectly fine from a climate perspective, even if the products are meaningless artefacts of a materialistic life that will never make you happy. I understand the impulse toward a simpler, less materialistic…

> If you consume and produce things in a way that doesn't release net CO₂ So far global output of wealth and well-being is directly tied to emissions and consumption of fossil fuels. We have a 110-year long precedent for that. You could even argue it started with the Industrial Revolution, so the period is longer. France is probably the only example of a country that came close enough to decoupling economic prosperit…

> France .. produce 5GT of CO2 per person.

5 GT (5 000 000 T) is unfathomably large. They produce about 5T = 5000 kg CO₂ / person / year, which is 5 · 12 / (12+2·16) = 1.4 ton of carbon / coal or 1.7 m³ = 1700 l of diesel.

Going by Wikipedia 2017 list[1], they are about 5% above average per-capita CO₂ emissions.

[1] https://en.wikipedia.org/wiki/List_of_countries_by_carbon_di...

Re: We need to take CO2 out of the sky – an overview of climate tech

#245

Post by lopmotr »

ouid wrote: post #232
lopmotr wrote: post #38

Earlier quoted context omitted.

It's not a quantity that has any natural zero, nor is time (year since Jesus?). So you can start it wherever you want.

that's not true at all. We're trying to measure the human impact on global temperature. The natural zero is whatever our best guess for the temperature would be without human intervention.

If it was constant, I'd agree, but the natural temperature was always changing and whatever it would have been today will also be changing. So you'd be graphing a different quantity, f(t) = temperature(t) - natural_temperature(t). From such a graph, you wouldn't be able to tell if a change was a change in the actual temperature or just a change in the predicted natural temperature. A predicted natural cooling would look the same as a human-caused warming.

Re: We need to take CO2 out of the sky – an overview of climate tech

#246

Post by ouid »

lopmotr wrote: post #245
ouid wrote: post #232

Earlier quoted context omitted.

that's not true at all. We're trying to measure the human impact on global temperature. The natural zero is whatever our best guess for the temperature would be without human intervention.

If it was constant, I'd agree, but the natural temperature was always changing and whatever it would have been today will also be changing. So you'd be graphing a different quantity, f(t) = temperature(t) - natural_temperature(t). From such a graph, you wouldn't be able to tell if a change was a change in the actual temperature or just a change in the predicted natural temperature. A predicted natural cooling would l…

This is already the case.

Re: We need to take CO2 out of the sky – an overview of climate tech

#247

Post by nnq »

pjc50 wrote: post #226
nnq wrote: post #203

Earlier quoted context omitted.

> It has killed every government that even dared to discuss it. And politically it is utterly impossible to defend Then pull it out of political discussion! We don't have political discussion about "how to hang people of color Q better" anywhere in the world (mostly) anymore because we've wrote it in the text of our f laws that violence and racial discrimination are forbidden! Not on the political menu anymore. Same…

I have some very bad news for you: there are lots of people actively trying to work to bring those back on the menu. It's almost impossible to put things "beyond politics" so long as someone wants to bring them back.

Once some things are off the menu, people need to work really hard to change things. And, more importantly, violence can be used against those people - I mean throw-them-in-prison type of violence, not more. Just like with freedom - in order to preserve it, you need to, "paradoxically", shut some toxic persons' mouths forcefully (eg. "hate speech").

Yeah, sure, you can philosophise in the most general terms but that's not how you get people and companies stop doing wrong things. You get them when the people/entities who want to re-bring the despicable things back into discussion can be fined / closed / put-in-prison etc.

I don't argue for eco-fascism. But with some things we need to be ruthless, especially in order to be able to carry on our peaceful, understanding and democratic discussions concerning all the other things!

Re: We need to take CO2 out of the sky – an overview of climate tech

#248

Post by jokoon »

HunOL wrote: post #175
jokoon wrote: post #133

Earlier quoted context omitted.

Except reducing emissions seems much more doable, safe and simple. It's just politically difficult. I have little hope that technology will be able to capture co2 in a manner that will be sufficient. I don't like those sorts of techs because people will brandish them as a solution, while it's highly unlikely they will help at all.

Changing minds and habits of billions of people is more simple and feasible? For me it's ridiculous. Any technological solution looks way better for me.

if no solutions is available and food security is threatened, minds and habits don't matter.

Re: We need to take CO2 out of the sky – an overview of climate tech

#249

Post by scythe »

avmich wrote: post #234
scythe wrote: post #230

Earlier quoted context omitted.

You can't get the energy back because I assumed you have a magical compressor that only compresses carbon dioxide. I didn't include any terms for compressing air. You get a slightly cheaper term (ca 420 J/kg) if you set the upper pressure to atmospheric but then you're storing gaseous CO2 which is not practical. But recovering energy by restoring the original [partial] pressure of 0.0004 atm is not possible unless yo…

Ok, let's take 500 J/kg of CO2. Do you think it's a lot? To get 1 kg of CO2 you'll need to process roughly a ton of air. There are ~5e15 tons of air in the atmosphere, so it's 3e18 J to process all the air. We produce annually 75e18 J annually on the planet - can we handle this expense? I'm afraid it will be more than that - but how much more exactly?

That is roughly accurate for describing the operation of real compressors.

The reason for calculating the bare minimum "magic compressor" cost is because it also applies to techniques like pressure-swing adsorption:

https://en.wikipedia.org/wiki/Pressure_swing_adsorption

Using PSA can reduce the energy cost of CO2 extraction significantly relative to direct compression technology. But because we know that the adsorbent is used in a cyclic process, we have dW[compression] = p dV + dE[adsorbent] and the long-time integral of dE[adsorbent] is effectively zero because the adsorbent cannot absorb or release energy forever, so ΔW[compression] = int[p dV] and thus any technology, compression-based or not, incorporating some finite amount of external components, is subject to the work limit.

This is also why, for example, thermodynamic analyses of engine types are always concerned about the possible compression ratio. You could consider the partial pressure of atmospheric and stored CO2 as the compression ratio of a hypothetical compressed-air motor, which can then be run to extract thermal energy (i.e. violate the second law of thermodynamics) from any process more efficient than 500 J/kg CO2, since again W[motor] = int[p dV]. You can improve the compression ratio by taking advantage of the P-T curve and performing the whole compression at the South Pole, which saves you about 100 J/kg.

Also, I was off by a factor of ten when I plugged in the vapor pressure of CO2. Correcting this is left as an exercise to the reader.

Technologies not subject to the work limit include e.g. olivine crushing, somehow inhibiting volcanic activity (???), planting trees, etc. Another technology I just thought of would be to to form CO2@H2O clathrates in seawater starting with air, which would also lower the compression ratio, and extracting the (solid) clathrates to recover CO2 and desalinated water. Here the pressure required is much lower and additionally desalinated water is produced; this only works if we form the clathrates in a cold environment and decompose them in a warm one, which is kind of inconvenient. Then again, shipping gigatons of fresh water to LA might become necessary anyway!

Re: We need to take CO2 out of the sky – an overview of climate tech

#250

Post by KozmoNau7 »

RobinL wrote: post #194
spodek wrote: post #174

Earlier quoted context omitted.

Glad to see reducing consumption at the top. People's scarcity mindset makes them think burning less fossil fuels and consuming less stuff will lower their quality of life. On the contrary, most Americans could reduce their consumption by 80% off pure life improvements . People convolve reducing consumption with returning to the stone age, which is a false dichotomy. It's more like exiting a mindset that stuff means…

Agreed. I spent some time making a calculator [0] to help me understand what matters when it comes to energy consumption. This made it very clear that by far the best way most consumers can make a difference is just to stop buying stuff. In the west we get away with 'low'(er) emissions because we import a huge amount of CO2 though imported goods - maps of total energy consumption are quite interesting here [1] Stoppi…

Breaking the constant want for new things is going to be hard. I know people who basically define themselves by their consumerism, some of them even fully believing that we can somehow consume ourselves out of this climate crisis.

I do try to argue that we should reduce our consumption and buy much fewer, but much higher quality items, which we repair and maintain for a long time, instead of throwing them out and buying a completely new thing.

But I am constantly met with arguments that "no consumption means no growth, and no growth means no life and no progress" and similar arguments. These people have really entrenched themselves in consuming more and more all the time.

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