2. You don't necessarily need a depleted natural gas reservoir to inject CO2 subsurface (though they sure are convenient) and there is plenty of room for CO2 subsurface. It also doesn't creep to the surface on any meaningful timescale.

3. How do we transport it there? Pipelines.

I feel like CO2 sequestration is second only to nuclear in the amount of unfounded concerns. There's one very well founded concern directly in the article - they estimate $50 per tonne of CO2 just to capture, let alone to store. My experience on a 2009 carbon capture plant design was that approx $100 per tonne of CO2 was the lowest carbon price that would really make carbon sequestration highly attractive and widespread.

I also happen to think a $100 per tonne carbon price is not such a bad idea. But it is possible that other technologies would beat carbon sequestration at that carbon price point. I don't know.

We have an excellent carbon storage technology, it's called coal. And what's best, it's already there, underground, very safely, proven for millions of years! With no cost!

But we're still building new coal plants in many places. In some places, coal plants and steel factories have shut down, but it's often because industry has been offshored to a place that uses coal, or they're replaced with natural gas, only a somewhat better alternative.

So if leaving coal unused can't be made to work, then more inefficient and thus expensive methods of carbon avoidance likely can't either.

It's like working hard in the car wash for the whole day and then at the end of the day, spending all the money you just earned on having your car washed. It's a bad strategy - you would have spent a lot less time and effort if you had just washed your car yourself.

When the coal and natural gas plants have been shut down, then carbon capture might have a role.

Nice page about world coal usage: https://www.iea.org/reports/coal-information-overview

We can't solve the crisis by trying our best not to disturb the status quo, things are going to get shaken up a bit.

Still very cheap. Promotes better sources of energy.

Nope, it's not a great time to be a coal-miner, but I hear Biden is trying to spend $4T on infrastructure so maybe some of those miners can buy a truck and form a road maintenance company instead!

If you're serious about getting rid of coal in the US, it needs to start with "We appreciate your and your family's work over the years, and here's a truckload of money and economic development for your region so that you can lay down that burden."

Nobody reacts favorably to doing a hard job, every day, and then listening to someone tell them they're killing the planet.

How the townsfolk there transitioned into that “doing it historically was good and necessary; but continuing to do it today would be dumb and bad” mindset might make for a good case-study. It’d certainly make for a more respectful and in-depth interview to do with them than just talking about the town’s name ;)

In case of coal, there's still _some_ demand though it's on the decline.

If carbon-heavy power generation didn't also emit particulate pollution, we probably wouldn't have a chance in hell. But thankfully, renewables and electric vehicle are also a solution to the pollution problem in many high-population areas.

But afaik, this will be the first time we're asking entire countries to forgoe huge things in their immediate best interest, in pursuit of a greater good.

The Montreal Protocol didn't touch as huge of a part of the economy, and nuclear weapons are their own ball of thistles.

Removing lead from gasoline is probably the nearest analog, although with a much lower adoption burden.

We really need to get rid of that “proud to kill myself to make my employer richer” trait.

> "We appreciate your and your family's work over the years, and here's a truckload of money and economic development for your region so that you can lay down that burden."

It’s only fair.

And there's a certain amount of pride in that struggle.

Sorry, but them's the breaks! Don't mean to sound harsh, but larger industries have died for worse reasons. What you do is what the wage earner did in the past: you suck it up and you move on because you have to provide for your family.

How many layers of industries have we invented and then rendered obsolete by subsequent industries? That number varies, in energy alone consider all the changes in distribution, extraction, etc. There has been a great deal of change in our understanding of the world since the invention of the coal industry, and it turns out coal is far more expensive than we realized.

I can see though why this seems synthetic, and why one would be motivated to challenge the assertion of fact. And it is true, that this argument is "synthetic" in the sense that it requires synthesizing many different observations spread over time and space using methods most of us aren't familiar with.

But a lot of us are swayed by the argument that using all this stored up energy in the ground has a side-effect of increasing the amount of CO2 in the atmosphere in direct proportion to that consumption, and that this in turn is unwanted because CO2 is opaque to IR, and it will increase global temperature.

There is a "false debate" about whether or not the global temperature is actually increasing. If you look at the data, or even just the satellite photos of the arctic over time, you should be convinced that there is no debate, and its just a simple fact. (And while a conspiracy that has modified those images is technically a possibility, I think there's enough on-the-ground evidence to back it up. If those Richard Attenborough narrated programs are computer generated, then they have rendering technology beyond anything in Hollywood.)

This simple assertion of fact (and its acceptance by a strong majority) has real ramifications for us in the most personal of ways, because it is a matter of the quality of life for our kids and grand-kids.

The scale of the change we must make is going to be big, and I think the coal miners are going to get the least of it. We Americans are all going to have to consider our consumption more carefully, become more frugal, more European. Our cars will shrink, and become electric. Our physical store options will become more limited, but computer mediated options more diverse, more local, more self-sustaining.

Ideally this change comes naturally as small town kids get educated in major universities in big cities, and are introduced to what I can only describe as an "Enlightenment Era Ethos", one that is rational, reasonable, skeptical, experimental (and innovative), and which is clearly convinced of the reality and importance of Global Warming. Personally, I'm convinced on first principles. Clearly energy expenditure we make, moving a 4-ton SUV 15 miles each way for one person to go to the supermarket, where each item comes wrapped in its own weight of disposable, nested wrappers that serves more of a marketing purpose than a "safe food delivery" purpose."

America can and must go through what I call the "Contraction", where life here becomes more European, communal, local and frugal in terms of the daily details of your life. There will also be the further embrace of a national safety net, and not just for old people. My hope is that cultural shifts will help major chains like Starbucks contract, too, being eclipsed by local cafes with better products, made with greater care, at similar prices, and giving more people the experience of running a business and being the boss! Heck, I would like to see the return of the local ISP business, just a rack of computers in an office park with battery backups and a person who knows how to maintain it all and secure it.

So, don't be fooled. American coal workers have an outsized influence on national politics in those states because reasons. Their jobs aren't more sacred than anyone elses and if they feel "tied to the land" or their "way of life", I tell them: I'm sorry. We will all need to change if we're to keep our ecosystem healthy by averting a possibly unfixible tragedy.

I will volunteer right now and in a legally binding way, to tutor, for free, any coal miner who wants to learn how to code for a living. Reach out via profile. First come, first serve.

It can't. Coal plants are dinosaurs that need to be shut down. Charging a carbon price is one way to make that happen faster.

This expensive part is for capturing CO2 out of ambient air, where you only get like 0.04%.

this is doubly good because it provides a great incentive for the free market to minimize the costs of CO2 sequestration and hopefully will let us hit the knee of the optimization curve asap.

Government here in Norway recently released their climate plan, and part of it was the gradual increase to 2000 NOK (~234 USD) per tonne of CO2 in 2030[1].

Not sure if it survives the years of politics between then and now though...

[1]: https://www.dn.no/politikk/erna-solberg/sveinung-rotevatn/kl...

I get the impression that the tax is to be levied on the entity that emits CO2 to the atmosphere, not the fuel producer?

What's also encouraging is that it's the right party fronting this suggestion. It's not a fringe left-wing environmental party.

Yes that seems to be the case[1].

> It's not a fringe left-wing environmental party.

Indeed, so will be interesting times ahead. Not unsurprisingly Norway has a very oil-oriented industry, which obviously did not think too highly of this proposal. There's lots of talk about transitioning to a "greener economy" but precious few concrete proposals about how to turn those jobs green.

So yeah, interesting times ahead.

[1]: https://www.regjeringen.no/no/tema/okonomi-og-budsjett/skatt...

Requirement to sell "carbon neutral" oil to countries that do not have their own carbon capture rules would be an interesting idea.

Could as well add another tax for all the other nasty chemicals the refinement process releases.

Yeah, I’m afraid I don’t buy this reasoning...

On the one hand I absolutely agree that's ignoring a major CO2 source.

On the other hand, if Norway added the CO2 tax to exported fossil fuel but other countries did not, would that affect fossil fuel consumption in any meaningful way?

So we have a hydro-carbon, we mix it with oxygen, and the oxygen combines with the hydrogen and the carbon, and releases heat as a byproduct. The heat energy increases the pressure of the newly created CO2. This higher pressure is placed on one side of a turbine or a piston, and we extract useful work by moving it from a high density state to a low density state, causing it to cool in the process.

Now it seems like if you want to re-concentrate that CO2, it should take at least as much work to compress it back to its original size as it released when you burned it in the first place, and probably a lot more, because the CO2 has been diffused into the general atmosphere.

To state it more succinctly, we extract work through a pressure differential, and by reversing that pressure differential, won't that require more work than we got out in the first place by the second law of thermodynamics?

I ignored the part where part of the energy is coming from the hydrogen. Is the hydrogen -> water where most of the energy is coming from, and the carbon part relatively insignificant?

1. Immediately after ignition, you have a low-volume, high-pressure, high-temperature amount of gas. Sequestration does not aim to turn CO2 back to this exact same state, but only a high-ish, average-temperature state.

2. Combustion often evolves more molecules of gas (look at the formula for the combustion of octane, and remember that water after combustion will be a gas). This increases the pressure, but is not something that needs to be reversed during sequestration.

3. Carbon dioxide isn't bad, but having too much in the atmosphere is. Sequestration doesn't aim to completely reverse the reaction in the first place, it just aims to remove it from the atmosphere so that it can't act as a greenhouse gas.

You run the hot, high-pressure gas through a turbine to give you less-hot, lower-pressure gas. You then extract as much waste heat out of that stream as you can via a heat exchanger process, to pre-heat incoming fuel/air and to recover more energy by boiling water to run through another turbine.

At the end of the process, you have a medium-temperature stream of combustion product that has high concentrations of CO2. You capture the carbon from this stream, before releasing the last bits of gas to the atmosphere.

You gain usable energy out of the process because all of the heat movement happens through a turbine (to directly generate energy) or through a heat exchanger (to recycle the heat to other more useful parts of the process).

Heat engines take advantage of the fact that expanding a hot fluid releases more energy than it takes to compress a cold fluid - the difference being that combustion energy. Indeed the pressure difference is only there to make the process more efficient - so long as there is a temperature gradient you can extract energy even with no pressure gradient.

So carbon capture hinges on the idea that we can find a low-energy route that involves a chemical reaction with CO2 that produces something that isn't a fuel but isn't gaseous CO2 either. And that we can find a LOT of it.

But consider for a moment how much coal and oil we've been digging up since the industrial age. CO2 is much less dense once it's uncontained underground. It won't stay liquid at that pressure.

In that case we'll need to have underground space of a size of many times the space that all that coal and oil took up, due to the lower density. Just pumping it there, forcing it underground in different spots etc will also cause significant ecological disruption. It's a lot of land we're going to be running pipelines to, drilling into to inject it, using heavy machinery etc.

And if some of it does end up being released due to a mistake, it can have potentially deadly effects. Like what happened at Lake Nyos. Safety would really have to be guaranteed.

I don't know, it just sounds like a solution that won't scale to the enormity of the climate problems, and rather more like big business wanting to monetise the problem itself (and also use it as an excuse to not reduce consumption).

But anyway, if it does prove itself in trials I would change my mind on it.

There are several entities working on this. Here's a company with a small pilot project, and links to scientific papers: https://www.carbfix.com/

Also, large parts of this planet consist of natural basalt deposits, every area with some current or historic vulcanism has them. E.g. half of Siberia is a huge basalt deposit. Google Siberian Trap. So I do not think artificial production would be necessary.

CO2 at 1200 psi will mix with oil very well and do wonders getting into pores, but to scale up storage there are not enough oil wells and we'd probably store in saline aquifers.

That's in the abstract, it's 2GJ/ton of carbon. So, it's roughly 1/20 of the energy generated by burning the carbon at the first place.

The great thing about a price on carbon is that the market would sort all this out.

Agriculture is a pretty diffuse source though. And ultimately, we need to take CO2 levels back down to 350ppm or so.

"Central estimates in the recent literature broadly agree that global mean sea level is likely to rise 20–30 cm by 20503,4,5,6,7,8,9,10. End-of-century projections diverge more, with typical central estimates ranging from 50–70 cm under representative concentration pathway (RCP) 4.5 and 70–100 cm under RCP 8.53,9,10,12, though more recent projections incorporating Antarctic ice sheet dynamics indicate that sea levels may rise 70–100 cm under RCP 4.5 and 100–180 cm under RCP 8.5, and could even exceed 2 m or more in far-tail scenarios4,7,8,11. Via a structured elicitation of opinion, experts now estimate there is a 5 percent chance 21st century sea-level rise will exceed 2 m"

Bad news for East Anglia and the Somerset Levels, and many estuary cities including London will need mitigation work.

#2 to be fair to OP, think they're referencing what would happen to humanity as a whole if we _didn't_ have carbon capture, not specifically "water world by 2100", and something I've picked up since moving to Boston from Buffalo is that storm surge has a _much_ more significant effect when you're around so much water. Even the 20-30 cm, once you add a foot or two of storm surge that we get a handful of times a year, floods most of Boston in 2050.

In the eyes of the annoying kind of climate activist, the affordability you've mentioned is a bug, not a feature. Too many people who claim to care about the planet want to use the climate as a pretext to reform everyone's lifestyle and to roll back industrial civilization more generally. This sort of activist doesn't see the carbon problem as an engineering challenge, but instead as a political and aesthetic project. It's super annoying, because people like this reject technology that would let us have our modern lifestyle cake and eat it too.

Not all climate activists are like this, but there are enough of these bad faith people around to seriously impair earnest and good faith efforts to solve the actual engineering side of the carbon problem.

Not roll back. But do smarter.

It's not just global warming. We're shipping billions of tons of stuff from one side of the planet to another in sulphur-blowing rustbuckets. Creating continents of floating plastic in the oceans. Causing toxic lakes from harvesting rare earth minerals.

We can't keep doing this. Maybe we can keep it up so before your lifetime is over, but sooner or later it's going to be a problem that can't be avoided just like climate change is now.

There's many quick wins here. Buying locally produced foods instead of stuff flown in from half a world away. Not flying across europe for a 1 hour business meeting. Reducing plastic packaging.

And there's good news too. We're continuing the excellent path of energy reduction in electric appliances. They had to keep adding "+"es and now rework the entire energy labels in Europe because "A++++" efficiency became too long.

I think COVID already brought us halfway there. We're no longer used to business meetings, the fragility of our supply chains has opened up many eyes, and most office workers now work from home at least part time and do just fine. For the environment this has all been pretty great :)

Some of it is also because externalities like pollution aren't priced in, but often the seemingly-bad thing is actually better by most metrics.

Reducing plastic packaging may be one such example: Sure, it reduces plastic waste, but it creates more wasted product, and packaging from stuff consumed in households is exceedingly unlikely to end up in the ocean in a western city that burns their trash in a waste-to-energy plant.

In the broadest possible sense, no, we can't keep doing "this": either we limit fertility somehow or we got the Malthusian limit eventually. That's just the consequence of the exponential function. And right now, whether population will stabilize on its own before we hit carrying capacity is an open question.

But if you hold population constant? Yes, we can keep doing this indefinitely, or at least until the sun boils the oceans in 500 million years or so. Why wouldn't we? There's every reason to believe that we can supply oranges in January to everyone.

Show me the math that says we can't. I'm not persuaded by rhetoric about rust bucket cargo ships. It's exactly this sort of sentimentality that makes it difficult to actually make progress on addressing actual climate problems.

It's not really an open question - it would take reversal of long lasting trends in large parts of the world to do more than at most delay the reversal.

We’re way off topic here but what the heck… in my entire life, I’ve not seen one single ‘population model’ play out accurately. We’ve seen dozens of popular ones that have failed to come true in the past century alone - what makes today’s different?

China is currently set to face a reversal somewhere from the middle of this decade to 1-2 decades away depending on who you believe. India is set to follow. Many smaller countries are also reversing around now, but those two for obvious reasons have a huge impact.

The last holdouts with high fertility are a handful of sub-Saharan states, with Niger by far the worst (Somalia second - the two are the only countries in the world left with fertility rates above 6), but even Niger is seeing fertility rates plummet as it's economic growth have sped up.

The estimates varies massively based on various scenarios. E.g. on a current trajectory, China will see its population halve by 2100. It's likely you'll see the Chinese government do a lot to prevent the decline from being that steep because it will be an economic nightmare to manage, and so we can't assume the trajectories will remain unchanged.

But nobody is actively trying to get much above-replacement fertility rates, so any political interference is likely to moderate delay the peak not prevent it.

[1] https://www.bbc.co.uk/news/health-53409521

Furthermore, fertility drops as education increases and poverty decreases. This trend is consistent in every population where we can correlate economic development. E.g. here's the fertility rate for Niger [1], one of the poorest countries in the world. Even that has taken a sharp downturn as economic growth has started decoupling from uranium export (which previously dominated Niger's GDP, but provided very little benefit to the population).

Niger, incidentally, has the highest fertility rate in the world, and is one of only 10 remaining countries with fertility rate above 5.

As such such "high fertility subpopulations" are really high poverty, low education populations - currently countries categorised as "Least Developed Countries" by the UN have a fertility rate of 4. Sub-Saharan Africa is the only region of the world that remains above 4, but that too is dropping fast as most of the countries in the region are seeing solid economic growth.

As poverty drops and education increases, fertility rates are dropping across the board, just not at the same rate. But even sub-Saharan African is headed for reversal.

[1] https://data.worldbank.org/indicator/SP.DYN.TFRT.IN?location...

It’s the same people who want everyone to keep using masks even after vaccination.

Is there a market for captured carbon? I understand there is a small market for industrial process and carbonated water, but are there people buying long-term capture in large enough quantities to make an impact?

Anyway, I don't think the price matters on that scale. Once we decarbonize electricity, I think it will be governments and non-profits that will do most of the carbon capture (unless there exists a large market for my previous question), and for those a lower price only means a higher rate of growth, not the difference between viable or non-viable.

The problem with CO2 capture specifically (specifically from the atmosphere as opposed to at the source) is that CO2 comprises a very small part of air. This means you have to move huge amounts of air through a capture device to capture a very small amount of carbon. How is that ever going to make sense?

If you rely on source emissions control only, you need finnicky source-specific installation and control technology everywhere, which greatly increases the cost and complexity of the implementation. And there are places where you can't realistically do carbon capture and sequestration, e.g. jet engines.

On top of all that, we live in a world with multiple governments and jurisdictions, and not all of them agree on the right level of investment in source capture. Do you really expect developing countries to give up on coal generation right away? What are you going to do, bomb them into the stone age? A climate management solution must be robust against the problem of uncooperative actors. We can't rely on everyone getting along and singing carbon kumbaya.

Compared to source mitigations, an atmospheric capture approach is simpler, more robust, and better capable of dealing with uncooperative emitters. Yes, you have to move a lot of air, but that's just energy, and energy is cheap if you're not picky about geography or uptime, and it's especially cheap if you're not squeamish about nuclear.

Global energy consumption is about 18 TW[1], so 2.4 TW is a lot but not outlandishly so. It makes sense to look at global energy rather than just global electricity, because the input to this process is heat. We'd need clean energy sources, but we have those. Since we need heat and can use a fixed amount of energy constantly, high-temperature nuclear reactors would probably be ideal.

It would be silly to do this instead of decarbonizing electricity production and converting to electric cars, but we also have to deal with steel and concrete production, agricultural emissions, long-haul jets, etc. Let's say we need one TW to cover emissions we can't easily decarbonize.

Nuclear power produced 2657 TWh of electricity in 2019.[2] Divide by hours in a year, that's 0.3 TW. Assuming 50% thermal efficiency, it's 0.6 TW of heat energy. So basically, triple the number of nuclear plants in the world and we can absorb 40% of our emissions.

Some of the high-temperature designs are fast reactors or thorium breeders. If we use either of those, we won't remotely strain our nuclear fuel supply.

There are other methods of absorbing CO2, like reforestation, topsoil restoration, and olivine beaches. But most methods have scaling limits. Direct air capture with basalt sequestration[3] and/or carbon-neutral fuel production could easily play a large role.

[1] https://www.theworldcounts.com/stories/current_world_energy_...

[2] https://www.world-nuclear.org/information-library/current-an...

[3] https://www.carbfix.com/

The energy needs which are hard to meet with renewables (aviation, other large-scale transport) are the same places where CCS is non-viable due to the efficiency hit.

The best we can do is decarbonise as quickly as possible, and live with the fallout of our failure to act this far - unless a significant use for captured CO2 is identified, atmospheric capture technology will always struggle with commercial viability.

And a significant use that does not end in it being released to the atmosphere after being used :)

Maybe it's viable for cement production as well.

There is no viable future scenario in which mankind's energy usage decreases. It's a pipe dream, and ultimately a dangerous one.

Energy use is fundamentally tied to progress to such an extent that we should always be looking for ways to increase the energy available to us.

Of course the energy should be produced in as low-impact a manner as possible, but it's long past time to accept that energy usage will go up, not down.

Plus we're nearing peak populations, after which the number of humans will be going down.

I agree more with the second point; the way that I'd say that is humans as a species will never self-moderate energy use.

For example, increasing fuel efficiency of cars does decrease energy use, because fuel cost is not the limiting factor foe most car travel. Similarly, more efficient lighting, more efficient home space heating and water heating, and better weatherization of homes, all increase energy efficiency and decrease energy use.

There's only so much lighting I would ever want to use, only so much heat, only so much time I want to spend in a car. Energy efficiency is one of the most powerful tools we have to reduce pollution, because it makes all the other things easier.

1. Elimination of resources

2. Excessive waste product (in this case, excrement and bodily wastes; pollution)

MPG from passenger car didn't decreased since 1976 despite huge advancement in fuel efficiency.

https://en.wikipedia.org/wiki/File:CAFE_mpg_curve_from_NHTSA...

1) land use decisions are pushing people further from workplaces

2) consumers are switching from the "car" class of vehicle to "light truck" which is negating fuel efficiency improvements [1]. There's a lot going on here, from people getting larger vehicles for perceived safety, to better comfort, to just having more money to spend on larger vehicles. Plus, all those people who think they need a truck despite using the bed once or twice per year.

3) Demand for gasoline is incredibly inelastic in response to price, with huge price spikes having almost no change in gallons of gasoline even as consumption in dollars spike [2]

[1] https://thenextweb.com/shift/2021/01/12/despite-ev-growth-ga...

[2] https://www.eia.gov/todayinenergy/detail.php?id=40893

It’s likely our industrial needs will continue to increase even with a smaller population

I'm all for aiming for high energy availability in the long run, but the idea that we can just keep increasing our usage monotonically (without a temporary reduction to get our shit sorted out) seems like the dangerous pipe dream to me.

Edit because I think maybe the tone sounded a bit short/unfriendly: I see a carbon tax as a necessary step in taking care of our issues, and my expectation is that this would reduce usage of fossil fuels quite significantly, temporarily. It seems likely that our energy budget would move more towards high-value-per-joule activities such as information technology and away from things like transportation. And I think this is a necessary step - people are currently quite careless about energy, especially about usage of fossil fuels, and I think if they become aware of its cost across a variety of activities they will adjust accordingly.

There is no viable future scenario in which mankind's energy usage decreases. It's a pipe dream, and ultimately a dangerous one.

Agreed. There would need to be crushing totalitarian rule over everyone on Earth to prevent progress, and that wouldn't be stable long term. Otherwise, competition by competing powers will inevitably result in a Kardashev 2 civilization. Here's why:

Space solar power and fusion power are a couple of serious tech/economic inflection points. Once humanity's technology and our self-organization reach that level of capability, we are literally within striking distance of threatening any star system in our galaxy with huge destructive energies. We only need one of the two for this to be the case. Fusion is unnecessary at this point. If someone can establish large-scale industry on the Moon and the asteroids, solar power will be every bit as good as fusion in many regards. (At large enough scales, solar power is fusion power, basically.)

Modern geopolitics are dominated by the logistics of energy transport and production. It has been this way since before World War II. The logistics of fueling factories, ships, then tanks and airplanes has absolutely dominated strategic thinking since even before that time. The lengths to which the allies went to provide the fuel to run the invasion of Europe were absolute feats of engineering, planning, and intelligence/disinformation. So just think ahead a bit: what if, instead of having to fuel your military, you could instead beam power to outposts, which would use that power to synthesize fuel? The side that can do that would have huge logistical advantages, which would also be strategic advantages. (There's a compelling reason why submarines and aircraft carriers are nuclear powered.)

Going further, once we are at the level of space industry at scale, the Earth becomes just one location in a much larger context, whose available energy dwarfs the available energy on Earth by many orders of magnitude. At those levels of available energy, we could build things like Shkadov thrusters and Nicoll-Dyson beams. At that point, we'd have the hypothetical ability to move stars and build devices that could fry the biospheres off of planets in the bulk of our own galaxy.

sure there is. reduce the population by a factor of 10.

you rang?

> In either case the solution is ...

well, thinking about it, no solution is also a good solution.

Estimated 30-50% mortality rate for babies and 1% per birth mortality rate for moms (times say 12 kids). Lotta innocent babies gotta die to achieve your goals.

While this may sound tongue in cheek or a gotcha. I do think people underestimate how terrible, hard and brutal it was to live in those cultures as a human. We definitely create our share of travesties as modern humans (factory farms, anthropogenic mass extinction events, global climate change making the world uninhabitable). It remains to be seen if we can use technology to out pace some of these problems we've created, but I'm somewhat hopeful that we can, and find a path forward to live humanely and sustainably.

So yes, scaling down is de facto against our moral values.

If we stopped that, and just consumed the food that nature spontaneously produces, it supports maybe 50M people. So first you'd have to kill 7000M people.

Even after that, I don't know how you'd stop people from reinventing agriculture.

So on balance, I recommend against this :)

There is a lot of excessive waste / inefficiencies due to energy being -- relatively -- cheap.

If energy prices soar, many inefficiencies will get more attention. Like, if food becomes more expensive we would stop throwing away 1/3 of it. (And more houses would get proper insulation. And so on.)

How would you get everybody to agree to accept all the limitations and ills of their non technological lives without wanting to reinvent modern civilization?

I don't see coal being an environmental hazard and that's carbon captured in the ground. Plus you have to ask whether some risk of leaks or whatever is worse than not even trying at all.

> I don't think we'll manage to do significant CO2 capture before the effects are irreversible anyway.

- Without joking: not with that attitude we won't. Let's not quit before trying?

- We need all solutions to develop and mature right now. If it turns out cement remains unsolved, for example, or maybe it's fertilizer that we can't find a solution for or we can't get the solution to farmers in low income countries, then having a way of removing said issue indirectly will still be helpful.

- There are different degrees to overshooting. A +3°C climate (already way too hot by current estimates) is still better than a +5°C. Maybe the runaway effects at +3 make it into +5, but also, those effects take time to run their course. Anything we do to slow down, reverse, control, it all buys us time to decide what options to deploy. "We won't manage anyway, why bother" is the only wrong path to walk down. Maybe we can adapt to +4, but without tech to reduce emissions or counter a runaway effect, it won't stay at +4.

When it's in the ground it's not, no. But when we try to take it out or put it back in it does cause significant environmental disruption. Especially open mining.

> - Without joking: not with that attitude we won't. Let's not quit before trying?

Because any effort and money we throw at this won't go to things that are more likely to work. The scale to make CO2 capture actually make a difference is huge. Even the thought of producing and siting all those capture factories is mindbogglingly difficult without creating even bigger problems. For example: If we have to ship all their machinery and steel from China, we're likely to emit more CO2 than they will capture in years.

Like I said I'm open to being proven wrong but I don't think it will ever scale to this level.

As long as you do not accidentally set it on fire ...

This is actually fairly close to Aachen, no?

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

Mental model of emission removal scope is some giant world system maybe 1x or 2x the size of the fossil fuel industry, trying to run in reverse what we've spent the last hundred or two years doing.

Carbon tax, carbon tax, carbon tax. Something significant like $250 / ton. Cannot come soon enough. Ideally a global carbon tax, failing that just between a few countries & with tariffs or sanctions or so on to penalize trading partners that don't regulate externalities of pollution.

And I agree about the carbon tax. It could even pay for some of the removal.

The strange thing here now in Europe is that greener alternatives like trains are taxed much higher than dirtier ones like airplanes. Because trains have VAT taxes on them, but the planes fly on kerosene that's exempt from tax and the price kept down due to international agreements.

As a result trains aren't a reasonable alternative and won't be for at least the next 20 years or so (as the train network would have to be scaled up significantly which would have been happening already if it was more a better alternative to flying). It's a shame because Europe is a great place for this with lots of short-distance trips.

Also if you believe the science, reducing energy usage won’t meet targets. The developed world will have to go carbon negative over the next couple of decades to counter growing CO2 emissions in the developing world.

*but so its all of the energy/money/effort that goes into modern fossil fuel extraction and processing so it isn't fundamentally impossible*

"Our hardest climate problems – the ones that are both large and lack obvious solutions – are agriculture (and deforestation – its major side effect) and industry. Together these are 45% of global carbon emissions. And solutions are scarce."

https://techcrunch.com/2019/02/15/how-to-decarbonize-america...

At the very least I think carbon capture makes sense for the long tail of industrial processes where the "CO2 emission" to "cost of reinventing process" ratio starts to get less and less favorable.

But even if you think we can decarbonize every last industrial process, we might as well develop carbon capture in case too much carbon gets emitted before that goal is achieved.

I wonder if this won't be a governance hazard in itself. What do we do after we create a global governance structure to reduce global emissions. We can't just tell people to stop using so much carbon.

I wonder if reduction causes more problems than it solves. Even if we magically could reduce everyones consumption, how do we deal with population growth assuming humans still produce some carbon.

I think we should really remove existing CO2 from the environment instead. Every ton of CO2 that can be captured and removed from the environment means some family in a poor country can enjoy the benefit of industrialization.

Of course we're already on a path of significant global warning so I don't think we have a choice either way.

But current global plan is to keep doing the first part, so we’ll have to undo it. We actually already likely have too much CO2 in the atmosphere. Even if we went to zero emissions today the climate would keep warming from the accumulated CO2 and feedback effects. Takes some years for those to work through the system.

What looks inefficient as far as pure physics goes, might be very efficient politically. Build some solar power plants in the Sahara, use the energy to sequester carbon, pay poor countries like Niger some money for that, reduce the current migration stream to Europe by creating local green jobs - that does not sound too bad.

Also, keep in mind that CO2 is not stored as a gas, but in dense phase (liquid-like), due to the high pore pressures at the depths considered (> 3000 feet), well above the CO2 critical point.

At these depths, any leakage to the surface would be negligeable unless you make a really lousy job in choosing your reservoir.

I agree that we should aim to reduce energy usage, but I would argue we would need to both. As often said, there is no "silver bullet" to dealing with climate change, only the possibility of a "silver buckshot", where we'll have to do many large changes at once. Even if we could transit to 100% "green energy" overnight, that alone wouldn't take care of more than less than half of current emissions.

A third of emissions come from industrial processes, much of which entirely unrelated to the energy used. In a nutshell, these emissions can be reduced using CO2 capture/storage, or alternatively we could stop making things such as steel, cement or fertilizer.

> Notably, it is projected that this solvent can operate at a regeneration heat rate of 2.0 GJ per tonne CO2 for post-combustion capture

Smarter Every Day did a video on it and atmosphere management on a submarine more generally which is pretty neat. The CO2 scrubbing is around 20 minutes.

https://www.youtube.com/watch?v=g3Ud6mHdhlQ

...and why not do exactly that?

Keep in mind, a capture solvent is something that will stably hold onto the CO2 at STP. It doesn’t need special care or treatment; the CO2 just becomes incorporated into its molecular structure, and now that complexed molecule is “what it is.”

So it’s not like we’d be pumping the mines full of pressurized gas. We’d just be pouring a stable, non-reactive liquid or solid in there. Even if the mine had an earthquake, caught on fire, etc., that wouldn’t leak the CO2 back out into the world. It’s not nuclear waste. It’s rock dust.

Of course, turning solar energy plus carbon dioxide into sequestered carbon and O2 is what plants do, but evidently not enough compared to human action. I do wonder whether biological (plants, algae) action, aided by genetic modification, could do more for atmospheric CO2.

Planting trees performs excellent on (1) but terribly on (2) and (3). According to Bill Gates' recent book on the topic (where he aims as best has he can to summarize the state of knowledge as per today), you'd basically have to make a big forest of the rest of the world just to offset US emissions.

In addition, it's not enough to plant trees, you have to plant trees where there wouldn't have grown any if you were not planting (i.e. making forest out of non-forest). This is going to put an additional huge strain on the need for land to feed more mouths, which is a problem that is only becoming more precarious.

The entirety of the Paris agreement has been a joke, cap warming? You can’t cap the warming, you need to put the earth into a stable situation to cap the warming, but that’s not possible. The earth’s climate has a number of positive feedback loops running, positive feedback loops don’t stop until either they run out of “fuel” in this case it would be greenhouse gases as the fuel, but with the permafrost thawing it will continue to thaw and release greenhouse gases, causing more warming, causing more gases to be released.

The other way to stop a positive feedback loop is a disruptive event. The climate positive feedback loop is massive so the disruptive event would also need to be massive, like a large meteor hitting the earth, or a super volcano erupting, of course both of those events would kill most life on earth, but it would stop global warming.

All we can do is witness what we’ve set into motion. What I think will happen is that through the acidification of the oceans the phytoplankton population will crash. Phytoplankton is the basis for the entire marine ecosystem, when that population crash happens, the entirety of the marine food chain will collapse quickly. 40% of the world’s population relies on the ocean as their primary source of protein.