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Comment by gruez | Hacker News Reader

>All you need is napkin maths. We gain energy by turning carbon into carbon dioxide. Now, we need the same energy to reverse it, but with a loss factor.

All the serious proposals for carbon capture involve use cases where it's unfeasible to swap in photovoltaics or whatever. For instance, fertilizer production, cement production, and air transport.

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Air transport is one of those things that would better offset with carbon capture - maybe even by making synthetic jet fuel, then it's carbon neutral - but very expensive. But really it doesn't matter. Air transport is 2.5% of global CO2. If we solved every other problem first, we could keep pumping oil for airplanes for centuries.

Take the engineer's mindset, reach the low-hanging fruit first. Replace coal with nuclear and natural gas, then start replacing natural gas. Cars don't need to run on gasoline anymore, BEVs are a superior technology. The market is doing its work to decarbonize that all by itself. Slowly at first, and then all at once. If you're middle-aged today, you'll likely live to see the end of gasoline cars. We can speed things along by removing subsidies on fossil fuels or offsetting them with green incentives.

The reason why nobody is replacing coal with nuclear is that the former is cheap and the latter is expensive. And at the moment, higher energy prices are a very though sell, politically, even if everyone agrees that we don't want to leave scorched earth for our kids.

Only because the coal power plant doesn’t have to pay for the negative externalities.

Crematoria will pay for their mercury pollution (from dental fillings) before lignite coal plants do.

Or just skip the nuclear power step and go directly to renewables with storage since it is vastly cheaper and the deployment time is counted in months rather than decades.

Unfortunately, solar w/ storage isn’t cheaper. You want to look at VALCOE for LFSCOE as metrics. It doesn’t compare solar roofing with nuclear since you need more transmission, but a distributed grid seems insanely unlikely to ever happen / be practical. Moreover, storage at scale requires strip mining the ocean floor which companies are getting ready to do. That’ll be an ecological disaster which makes nuclear accidents look like peanuts.

See the recent study on Denmark which found that nuclear power needs to come down 85% in cost to be competitive with renewables when looking into total system costs for a fully decarbonized grid, due to both options requiring flexibility to meet the grid load.

  Focusing on the case of Denmark, this article investigates a future fully sector-coupled energy system in a carbon-neutral society and compares the operation and costs of renewables and nuclear-based energy systems.

  The study finds that investments in flexibility in the electricity supply are needed in both systems due to the constant production pattern of nuclear and the variability of renewable energy sources. 

  However, the scenario with high nuclear implementation is 1.2 billion EUR more expensive annually compared to a scenario only based on renewables, with all systems completely balancing supply and demand across all energy sectors in every hour.

  For nuclear power to be cost competitive with renewables an investment cost of 1.55 MEUR/MW must be achieved, which is substantially below any cost projection for nuclear power.

https://www.sciencedirect.com/science/article/pii/S030626192...

Or the same for Australia if you went a more sunny locale finding that renewables ends up with a grid costing less than half of "best case nth of a kind nuclear power".

https://www.csiro.au/-/media/Energy/GenCost/GenCost2024-25Co...

But I suppose delivering reliable electricity for every customers needs every hour the whole year is "unreliable"?

Please do show a study which says that we need to ”strip mine the ocean floor”.

It does sound like typical fossil lobby misinformation.

> Please do show a study which says that we need to ”strip mine the ocean floor”. It does sound like typical fossil lobby misinformation.

Then why are companies gearing up to literally do this to satisfy the needs of battery manufacturing?

https://www.youtube.com/watch?v=VIXbKptKSs4

https://www.youtube.com/watch?v=qW7CGTK-1vA

Denmark generates 20% of its energy from renewables which is about on par for what most countries see. Let's see how much those renewables start costing when you need to supplant the 80% of the energy grid which is still is still carbon producing. Which is my point - renewables can't scale past this threshold and trying to make them raises the costs exponentially. Compare this to France which has been >90% decarbonized in its grid since at least the 90s.

Re fossil fuel propaganda, the number 1 supporters of renewables is the fossil fuel companies. It's not because it's the future but because it prolongs to the utmost the transition off of fossil fuels while appealing to the sensibilities of people who style themselves as "environmentalists". No country that has invested in renewables has yet managed to get off fossil fuels while France invested in nuclear & nearly completely decarbonized.

How can you spread all this misinformation? Do you believe it yourself?

Yes, there has been companies trying to exploit the ocean for mining for as long as we have been traveling the seas. There has yet to be a successful attempt at it.

Then a lovely apples to oranges comparison comparing primary energy of one country to electricity mix of another.

Lets do the real comparison, the one you did not want to do because it does not show France is as a favorable light:

Primary energy mix using the substitution method[1]:

- France: 51% low carbon

- Denmark: 43% low carbon

Then we have electricity mix [2]:

- France: 92% low carbon

- Denmark: 88% low carbon

France is wholly unable to build nuclear power as evidenced by the Flamanville 3 program being 7x over budget and 13 years late on a 5 year construction schedule.

The EPR2 program is in absolute shambles due to the insane subsidies required, and now "hopefully" will reach an investment decision (i.e. the government decides on the subsidies) in 2026.

We should keep our existing fleet of nuclear power as long as it is safe, needed and economical.

But only someone with vested interest in the outcome of the nuclear industry would suggest wasting trillions of dollars on nuclear subsidies in 2025 given the state of renewables and storage.

> No country that has invested in renewables has yet managed to get off fossil fuels while France invested in nuclear & nearly completely decarbonized.

And the misinformation continues. When is France going to decarbonize the remaining 48% of their economy?

[1]: https://ourworldindata.org/grapher/per-capita-energy-source-...

[2]: https://ember-energy.org/data/electricity-data-explorer/

How can you believe such blatant fantasies? 90% of added peak energy generation is renewable. Do you think companies do that because it's more expensive?

How do you explain it?

We're already way overgenerating for peak generation while persistently not solving the baseload requirements which is where we need to decarbonize. Or in simpler terms, government subsidies distorting the market and solar chasing the easy 20% of the grid supply it is better suited for while ignoring the rest of the market because it's a bad fit.

Storage decreased fossil gas usage in California 20% YoY in 2024. It is being solved as we speak.

> BEVs are a superior technology

While BEVs have a lot of benefits, they are still objectively inferior to ICE vehicles. They’re (in most cases substantially) more expensive, less energy dense by mass and volume, and require planning for refuelling (especially if used in areas outside of main city centres or for long driving, or if you live in an apartment without access to a charger at home). Not to mention most grids being nowhere near able to support the entire population of car drivers fast-charging their cars during rush hour. Gasoline-powered cars are objectively easier to own and use.

The real solution is public transit, and convincing people for whom public transit is impossible that switching to BEVs is worthwhile, even with their drawbacks. Telling people that BEVs are superior technology is counterproductive though, when there are still very clear problems with them.

> They’re (in most cases substantially) more expensive, less energy dense by mass and volume, and require planning for refuelling (especially if used in areas outside of main city centres or for long driving, or if you live in an apartment without access to a charger at home).

The most popular BEVs already cost less than the average new car and the price will continue to decline as long as battery prices do. Ranges of ~300 miles are common, meanwhile the average commute is 42 miles, so charging at home is sufficient for the vast majority of usage and is more convenient than buying gas. Apartments will install chargers as electric vehicles become more common.

For long trips, you begin your day having charged overnight and then add 200 miles of range at a supercharger in 15 minutes. That 500 miles is more than 8 hours of driving at 60MPH and it cost you 15 minutes. For people who make such long trips on a regular basis there will be cars with larger batteries and more range so that "overnight plus once in the middle" gets back to being just overnight.

> Not to mention most grids being nowhere near able to support the entire population of car drivers fast-charging their cars during rush hour.

This is the least interesting problem. Upgrading power grids is a known process involving only widely deployed existing technologies.

> The real solution is public transit

Public transit doesn't work in the suburbs, the majority of the population lives in suburban or rural areas and changing that would take decades of new housing construction which is currently prohibited by law.

Why wouldn’t it work in the suburbs?

Current suburbs are quite low-density due to roads and front-yards pointlessly wasting space. It works fine with Japanese-style suburbs, but car-centric suburbs need those front yards to cut down on the sound of fast-moving cars directly outside the house (and reducing speed limits in suburbs down to 5 or 10 is utterly unthinkable for most people), and they also need a 2-car garage with another 2 car spots on the driveway and then another 3 spots on the curb, in case they need to park 7 cars at once for some reason and all their neighbours do too.

It works in plenty of Australian suburbs, which seem pretty car centric. I don’t know how they compare to Japanese suburbs.

Australian housing prices are literally some of the highest in the world; we're in the middle of a housing crisis. It might "work" in that sense that with sufficient mineral exports, we haven't gone bankrupt yet, but it's horrifically inefficient. Sydney housing prices are higher than in Tokyo.

That’s totally irrelevant to whether you can implement public transit in a suburb. If you were actually talking about Australian suburbs in your first comment then you were wrong.

> Why wouldn’t it work in the suburbs?

The number of cars per hour during most of the day on a suburban street is commonly around one. If a bus runs that frequently it would have one passenger and all you've done is replace one midsized car with one large bus at significant expense. If the bus runs less frequently than that it would have zero passengers because people will buy a car and drive it themselves rather than wait that long for a bus.

This is already being somewhat generous by assuming that people would be willing to wait the balance of an hour for a bus. For mass transit to actually work you want service every five or ten minutes.

> Not to mention most grids being nowhere near able to support the entire population of car drivers fast-charging their cars during rush hour.

Feels a bit like a straw man. Most commuters aren't extending beyond the range of their vehicle for work commutes, and would charge at home or office on solar. I agree they should not be sold as though there are no trade offs, but after extensive research it feels that for a primarily commuter scenario, never having to stop for gas, charging at home, etc, would be not only practical but actually superior. I frequently have to gas up mid week and with a busy job and kids, it is an actual hassle that would be nice to be a nice upgrade.

I can tell you don’t own a BEV.

The range is a non issue 99% of the time when you’re driving around in your city. Charging at home is both cheap and super convenient.

Maintenance is cheaper, the car lasts longer.

I don’t know a single person who buys a BEV and goes back. I know many who go the other direction.

And as adoption rises and technology improves the case will get stronger and stronger.

> I can tell you don’t own a BEV.

I don’t - my daily cost $1400USD, I don’t think there’s an EV on the planet that will work out cheaper before its batteries fail. Ignoring that I’d prefer one that could tow at least 5k lbs (which I make use of fairly frequently on my daily), seat 6 adults, cost only ~$300/year in maintenance (including tires and brakes), and go 750km without thinking about refuelling. And ideally would be comfortable and have good ride quality, which the vast majority of modern cars simply don’t (unless you spend far too much money).

> The range is a non issue 99% of the time when you’re driving around in your city. Charging at home is both cheap and super convenient.

I don’t live in the city, and trips to the city are minimum 50km round trip. Doable with most EVs, but that’s assuming I don’t actually go anywhere in the city. I also have to account for winter temperatures going below -30 relatively frequently, so would have to divide advertised range in half to account for regular worst-case conditions. And for used cars, maybe even more, especially if trying to hit anywhere close to the price point I pay for gas cars (and having to buy a car with older batteries).

I don’t go into work frequently, but when I do, it’s over 100km round trip, assuming I make no stops. That rules out pretty much all small “city” EVs when taking into account range loss in the cold.

Charging at home would be convenient, but I live 30 seconds from two gas stations, so I doubt it would be notably more convenient than that.

> Maintenance is cheaper, the car lasts longer.

Which EVs are known to last 3-400k miles without needing new batteries or having substantial range reduction? That’s what I anticipate out of my current car with only a ($1000) transmission rebuild at ~250k miles. The engine should outlast the car. Suspension components last ~200k miles, front brakes last 75k, rears last 150k. Tires last 40-60k and cost $500 for good ones.

> I don’t know a single person who buys a BEV and goes back. I know many who go the other direction.

Offhand I know at least 4. Mostly when they realize that “hey, my range has cut in half during this cold snap and I won’t be able to make it to X” or when they do the math and realize the extra $6-20k they spent they’re not saving in gas and maintenance before they buy another new car in 3-5 years. The ones who keep buying EVs usually do it for the image, or because they’re willing to spend substantially more money and sacrifice some convenience to drive a greener car. Most of both of those types (at least in my experience) also own a new luxury truck for hauling toys and taking kids to hockey, going on camping trips and that sort of thing.

> And as adoption rises and technology improves the case will get stronger and stronger.

I agree! But they’re not there yet. I would really like them to be, so that fewer people are buying gas cars who just want “a car.” I’d be happy to buy one myself if it made sense, but unfortunately it doesn’t.

Charging at home is often more expensive than gas in much of California and Hawaii but yes generally cheaper to run if you ignore vehicle cost and lifespan.

> While BEVs have a lot of benefits, they are still objectively inferior to ICE vehicles.

This hasn't been true for a couple of years. China is an excellent example of that, its market flipped to EVs virtually overnight once the benefits of EVs became clear. Last year, 48% of all the new cars sold in China were EVs, and this year it's projected to be around 60%.

> The real solution is public transit

No, it's not. Public transit is nothing but a distilled misery concentrator. Transit is also _not_ more CO2 effective than small-to-medium EVs when the carbon footprint of their _drivers_ is taken into the account.

Mass transit is fine in the tiny fraction of areas where there's sufficient population density to make it viable. The total area of major metro areas in the US is something like 110,000 sq mi, or slightly larger than Colorado. What are your proposals for the rest of the country?

~80% of the population lives in cities. If we transition over cities, then we've solved most of the problem already.

Uh uh. That 80% figure includes suburbs, exurbs, and all manner of low density residential settings where mass transit is uneconomical. So now what?

If you only include sufficiently dense areas, what percentage of the population do you get? I suspect it's still high enough to make a big difference.

And, honestly, I think some number of people would be willing to move into denser areas if there was good transit, so it's a problem that might work to solve itself in time.

I'd love to figure out a way to come up with concrete numbers here. Any ideas?

ArcGIS or other geospatial program and access to quality population density polygons via r/datahoarders or other community that can point out sources for you.

(and recommend tooling - PostGIS is likely ok for this kind of thing without too much effort (fingers crossed))

It's a learning curve if you haven't done such things before, perhaps worth it if such questions interest you.

You'll also be doing some seat of the pants Fermi estimations so it's be handy to run your thoughts past others that are into that kind of thing.

Much appreciated, I'll look into it!

Rail works just fine in the suburbs of Sydney, Australia. It's not great, but it's still cheaper than cars.

Besides, if you care about costs then suburbs/exurbs are fundamentally uneconomical in general - most of the cost of housing comes from the land, of which suburbs are fundamentally wasteful. Literally everything there is (relatively) uneconomical, and is only widespread because the alternative is literally illegal.

>Rail works just fine in the suburbs of Sydney, Australia. It's not great, but it's still cheaper than cars.

Cheaper like cheaper or cheaper like more expensive, but subsidized by taxpayers who don't use it?

Haha there's a rhetorical question if ever I've seen one.

Most of the cost of housing absolutely does not come from land except in massively overpopulated cesspits. Proof: a 1600 sq foot single family home on an acre of land is going for approximately $350k here currently. At current land valuation $30k of that is the lot. I live 15 minutes away from one of Apple's satellite offices so we aren't talking a ghost town in Nevada either. Cities suck, as does the expectation that everyone crowd into one.

It's uneconomical only where little used. The conundrum for suburbs is not to put bus lines or trams in, but to get people to switch. Once/where widely used, these services pay for themselves. But an empty bus costs more to run than one single-occupant SUV, that's true. And it can never match the "convenience".

> While BEVs have a lot of benefits, they are still objectively inferior to ICE vehicles.

There are multiple dimensions in which they differ. Cost, reliability, emissions, safety, convenience, driving enjoyment, etc. To compare them and say one is better overall than the other requires you to define the weight that you place on each of those factors.

Many of those weights are subjective. Some people value convenience a lot. Some people don't. Some people passionately love driving a stick shift, and some people hate driving. Some people believe climate change is the most important issue of our time, and some people don't care if the planet is trashed as long as it doesn't happen within their own lifetimes.

Since the weights are subjective, it is a logical impossibility for one of them to be objectively inferior or superior.

Agreed on public transport being the real solution, but BEVs will be much cheaper (than ICEs) in the long run - they have far fewer moving parts, and they're only near the beginning of their learning curve, unlike ICE cars which have been expensively mass-produced for over a century at this point; they're not getting much cheaper.

but BEVs will be much cheaper (than ICEs) in the long run

That presupposes leaps of improvements in battery technology and battery recycling. Right now, the maintenance cost of a BEV is roughly $1,000 per year on battery replacement costs alone, and while I'm sure those costs will go down over time, they need to drop by 90% to be cost-competitive with ICE cars. That requires new materials that aren't on the science horizon yet, FAFAIK.

That's funny: maintenance only costing $1,000/year sounds great compared to the ICE vehicles I'm accustomed to.

You should buy more reliable vehicles, then, if you care about maintenance costs. Ignoring tires, my maintenance budget for my daily is about $200/year, and including them, averages ~$300/year. With above average mileage per year.

Life is full of trade-offs: if I did that, I'd have to carry a loan, which would in turn require a more expensive insurance policy, and then I'd be committed to a greater monthly outlay for the vehicle's financial maintenance than I typically have to expend for its physical maintenance. That kind of leverage probably makes sense for people who have a car at the center of their life, but that's not a way I'd like to live, so I accept the occasional mechanic's bill as the price of greater flexibility in my life as a whole.

plenty of 35mpg beaters in the sub 10k range. How about learning to turn a wrench?

For sure there are - I currently drive a '96 Toyota T100, which I bought for $5500 a few years back. It is reliable as hell, but the miles take their toll, and one must keep up with the maintenance. Timing belt, water pump, brake calipers, starter motor, etc... they wear out, and it adds up; but it still costs less overall than a newer car would.

I've done plenty of wrenching in my time, out of necessity and enjoyment alike (used to do a lot of jeeping, then motorcycling), though these days I usually prefer to employ professionals. That's why I prefer older vehicles I can afford to buy outright: I can trade time against money, depending on which I happen to have more of at the moment, instead of being locked in to the fixed monthly expense I'd have with a low-mileage car.

Timing belt is a 10 year maintenance item. ~1000 dollars mostly labor

Waterpump is replaced at the same time as the timing belt, and they rarely fail now a days. ~ 300 bucks for one as added part during the timing belt labor

I assume you are talking about brake pads as calipers rarely fail, 5-7 year maintenance interval, easy DIY job ~500 for a set of 4.

Starter motors also very rarely fail I've had the same one for 20 years in my rx8 hpde toy. Even still they are ~200 bucks and literally 2 bolts and 30 minutes of time.

We havent even hit 2000 dollars yet in critical maintenance over 10 years. If you actually knew anything about wrenching you wouldn't be saying newer cars are easier and cheaper to work on either. I dont know how you are doing 1000/ year on maintenance on an ICE but then again you presumably offroad " jeeping " which would make your experience an outlier on what commuter cars actually experience for yearly maintenance.

You just want to nitpick, I see. I'm not interested. Have a nice day!

You asserted that ICE maintenance is cost prohibitive, but when I break down the cost its called nitpicking? New car note cheaper than maintenance. Yeah youre a wrenchlet. bye

You are mistaken; I never said any such thing.

Someone quoted a figure for electric car maintenance, as a downside to the technology. I remarked that this actually sounded pretty good, relative to my experience with ICE cars. Someone else observed that I could choose to buy cars with a lower maintenance cost. I agreed that this was true but explained why I prefer to do things the way I do. Then you came along with a chip on your shoulder and started griping, for reasons known only to yourself.

>Someone quoted a figure for electric car maintenance, as a downside to the technology.

It is a downside compared to ICE maintenance which is significantly lower.

>Life is full of trade-offs: if I did that, I'd have to carry a loan

to which I replied there are plenty of cars sub 10K which you wouldnt need a loan for and that you could easily maintain for less than 1000/year

>I remarked that this actually sounded pretty good, relative to my experience with ICE cars

When I broke down the cost of the maintenance items YOU listed as over 1000/year over 10 years I said that those items you listed dont need maintenance every year, and the cost of replacing them is far less than 1000 dollars a year. To which you replied that I was nitpicking

> Then you came along with a chip on your shoulder and started griping, for reasons known only to yourself.

Im not griping I am just telling you that you are wrong when you say that 13k/10 years is cheaper than the maintenance items you listed. Just like the other guy said.

Then again you own a jeep and you know what they say about jeep: Just Empty Every Pocket :P

>That presupposes leaps of improvements in battery technology and battery recycling.

No, it's just basic extrapolation of the learning curve of EVs compared to ICEs. Even if the battery stays the same price, the fact is that the battery is only ~$5000 in price out of a $30k vehicle. The other 5/6ths of the cost have room to drop. Not to mention, the battery cells might not be new but the battery pack (i.e. the big box that you put all the battery cylinders/rectangles into) is new.

>they need to drop by 90% to be cost-competitive with ICE cars.

lolwut

>the maintenance cost of a BEV is roughly $1,000 per year on battery replacement costs alone

wut

wut

Maybe do some research before proudly displaying your ignorance for everyone to see? A replacement battery for everyone's favourite yardstick costs (from [0], the first search result):

    Anywhere around $13,000-$20,000 for Models S
    At least $14,000 for a Model X premium SUV
    At least $13,000 for a Model 3 entry-level sedan 

  No matter the model or manufacturer, all EV batteries last for 10-20 years

Do your own math, or provide your own references.

[0] https://www.jdpower.com/cars/shopping-guides/how-often-do-te...

> While BEVs have a lot of benefits, they are still objectively inferior to ICE vehicles.

Saving the world may require some effort and inconvenience.

"But really it doesn't matter. Air transport is 2.5% of global CO2."

Because most people still cannot afford flying. If the world gets richer, more people want the privilege of flying. And it is not like we have an excess budget of CO2. Everything we reduce helps, so a carbon tax on jet fuel might be a good start. That is a low hanging fruit.

Spreading nuclear reactors worldwide really is not. That would be a very hard fruit, with lots of potential side effects. Or do you think bangladesh will build to standards you think are safe?

The first two examples are feasible, the last not so much.

You need extra energy to power the CCS, and to store the captured CO2.

That's not practical on any airliner. One kilo of jet fuel produces about 3.5x its weight in CO2.

The solution to aviation is "fly less", also "don't air-ship fresh produce which can be moved by sea or road" (and if it can't, don't ship it).

Sorry gents, those Kenyan roses for Valentines are over. Get your loved one some tulips instead.

>You need extra energy to power the CCS, and to store the captured CO2.

>That's not practical on any airliner. One kilo of jet fuel produces about 3.5x its weight in CO2.

Carbon capture includes direct air capture, which doesn't come with any weight constraints.

>The solution to aviation is "fly less", also "don't air-ship fresh produce which can be moved by sea or road" (and if it can't, don't ship it).

Any solution that's predicated on "do it less" is going to be DOA politically. The options available voters aren't "electric planes" or "don't fly", they're "do something" or "do nothing". Telling people they're going to have to make upfront sacrifices for vague future benefits is going to be a losing proposition politically. Any solution to climate change is going to have to come from technological advances, not getting people to consume less. US emissions per capita has dropped more than 25% since 1990[1]. That's not because people ate 25% less meat or drove 25% less.

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

How much does diffuse DAC cost?

Add the price of that on a flight ticket (which we ultimately have to anyway) and we'd be helping address the problem already, before the tech is even deployed.

And the next 35 years - to 2060 - have to be a much steeper reduction than 25%, or the 35 years after that will, one way or another, represent a _forceful_ reduction of a lot more than 25%.

Finally is that 25% on a production or consumption basis? Offshoring and deindustrialisation are not trends that are likely to continue, again more for political reasons than anything else.

>How much does diffuse DAC cost?

>Add the price of that on a flight ticket (which we ultimately have to anyway) and we'd be helping address the problem already, before the tech is even deployed.

It's $1000/ton today, which works out to a 70% price increase for a new york to london flight. I disagree that would "address the problem already, before the tech is even deployed", because zero chance anyone would vote for it in the first place. That's where technological advancement comes in. Startups claim they can hit $250-$350/ton by 2030[1], which is a much more manageable 21% increase.

>Finally is that 25% on a production or consumption basis? Offshoring and deindustrialisation are not trends that are likely to continue, again more for political reasons than anything else.

It's around 17% on a trade basis[2], but the point stands. Americans haven't eaten 17% less meat, drove 17% less, or bought 17% less stuff.

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

[2] https://ourworldindata.org/consumption-based-co2

It remains infuriating to be repeatedly lied to by politicians who say they can "hit net zero" etc without any lifestyle changes.

It is utter nonsense and simply ensures every conversation on the topic is grounded largely in fantasy.

There are hard choices to be made and we insist on letting people pretend otherwise. It's infuriating

Unfortunately Americans as a whole would rather have climate change than lifestyle change. That’s a good portion of why Trump is president now. And most countries are in the same position, or want lifestyle change in the sense of using more energy.

If technology can’t do it, more climate change is inevitable.

Then they presumably understand climate change in terms of occasional weather disasters and hot summers and not, say, twenty years of chronic and persistent inflation followed by actual food shortages.

The hard choice has been made. The world has decided to accept climate change in order to continue using fossil fuels. It's just not the choice you (or I) want.

While I think some lifestyle changes are a good idea:

There's so much we can convert to renewable and electric power without any meaningful lifestyle changes or even a particularly large amount of money relative to the size of the industries involved.

And for the rest, it would cost money to keep the same lifestyle, but GDP per capita keeps rising and if you hold lifestyle constant then that gives you lots of money to spend on big goals.

What's utter nonsense and fantasy about that?

> Any solution that's predicated on "do it less" is going to be DOA politically.

I agree with your analysis. The problem here is if we're both right society is fucked, end of story. There are no convenient solutions to replacing our species primary mode of energy generation and mobility, that drives an industry that is quite literally the hub around which the entirety of the rest of the global economy revolves. Available credible solutions all require a kind of political will not seen in several generations.

The solution we have are renewables.

Today renewables produce vastly cheaper energy than fossil fuels and are disrupting every industry that can use electrical input or batteries.

The problem is the use cases where we utilize either the density of fossil fuels or as feedstock in industrial processes.

Which brings the ”Hydrogen ladder”:

https://www.linkedin.com/pulse/hydrogen-ladder-version-50-mi...

What we need to do is to continue scale renewables so they become cheap enough to by merit be the energy input for the hard to decarbonize fossil energy/feedstock use cases.

See fossil fuels like todays version of the piston steam engine used in for example locomotives.

It works but is inefficient and expensive to maintain compared to ICEs or gas turbines.

Nope. We want renewables to be a solution but they're all predicated on various flavors of non-renewable unobtanium and do literally nothing to address (among other things) global agriculture's absolute dependence upon petrochemical inputs or global logistics as a concept. The actual solution would be aggressive managed degrowth in conjunction with renewables and ag-based sequestration projects. The irony here is degrowth is absolutely guaranteed at this point, the only question is does it happen in a managed and planned fashion or does society collapse. All current evidence suggests the latter.

Please do tell me which "minerals" we are lacking for the renewable transition.

Did you even read the Hydrogen Ladder?

Fertilizer sits at the top as "must be hydrogen based with no real alternatives". It is one of the hardest sectors to decarbonize since we need to get the price of renewable based fertilizer to be equivalent of todays fossil based one.

Then just typical degrowth. Maybe we should cull the top 10% of the world? Starting with you and me?

Copper, for one. Go have a look at what kind of overhaul to the global transmission grid's required to meet projected growth and get back to me with your prospectus for mining the asteroid belt. Ironically individuals in highly specialized economic niches living in high tech societies are going to have it a lot worse than more self-sufficient agrarian arrangements so odds are yeah, you and me, after the water wars have done their work globally of course.

I don't think the idea is to have the capturing machinery on the plane itself. The idea is to have capture machinery on the ground, offsetting the carbon released by the plane.

That's right, but then you have to capture it from atmospheric concentrations (430ppm) rather than directly from a waste gas stream at a much higher concentration.

It can be done but the economics don't look good right now. Possible very cheap solar energy in desert regions can change that a bit. Australia have been trying but they didn't get very far with it yet, granted there is still room for solar to get cheaper again.

Luckily CO2 is fairly fungible. Instead of the airplane capturing its own CO2 we can just capture 3.5t CO2 on the ground for every ton of jet fuel fueled into an airplane.

If the entire world's electric supply isn't decarbonised at that point then that money would be better spent on deploying renewables somewhere without a 100% clean grid as the article says or electrifying heat or industry.

That has issues with proving the deployment actually displaces carbon but carbon capture has similar issues proving that the carbon is actually permanently removed.

That's the thing. All of these mitigations are meaningless if we still have vast industries predicated on burning fossil carbon.

And once we've eliminated the burning of fossil carbon, the mitigations are unnecessary. Nature will gradually find an equilibrium, and anything we do to speed it up (even removing carbon) is as likely to cause harm as good.

Maybe there is a future where we have so much extra renewables that we can think about trying to undo what we've done. But any effort spent on it now feels like an attempt to decrease the need to eliminate fossil fuels as fast as possible.

> we can just capture 3.5t CO2 on the ground for every ton of jet fuel fueled into an airplane

Entropy makes one of these much easier. For planes, synthetic jet fuel is the answer.

The sign we’re taking jet emissions seriously will be when someone drops the flygskam and hydrogen shtick and passes a synthetic-fuel mandate on private jets. (Less than 3x the cost in America [1].)

[1] https://www.reuters.com/sustainability/us-sustainable-aviati...

Aviation fuel has a trivial replacement in renewable biofuels, and three nontrivial replacements in liquid hydrogen combustion, liquid hydrogen fuel cells, and for short flights in battery power.

>trivial replacement in renewable biofuels

That's basically direct air capture with extra steps. All the carbon in those biofuels is coming from somewhere (the air).

Yeah, but you basically are using self-replicating solar-powered machinery (aka "plants") to capture it.

Maybe I'm just stupid but if all the planes in the world used biofuels, wouldn't that mean that flying is net-zero carbon (at least as it comes to fuel consumption)?

Like you do your flying, release CO2, but that CO2 gets captured again... I mean that doesn't sound bad, right?

It's not going to reduce the level of CO2 in the air right now, but it would stop further increases... which, mathematically, seems to be the same thing as if we kept the status quo and did something else to reduce CO2 output? What am I missing?

Yeah. Except it isn't so unbelievably terrible on both capex and opex as mechanical DAC.

Biofuels as in from farming? Modern farming just turns oil into crops, so turning the crops back into oil is a non-solution. The only viable current biofuels work by turn leftover waste matter into fuel - in other words, recycling.

Also, any farming done for primary energy is farming not done for food.

NO problem, we just cut down a few more rainforests or similar to make room for more farming.

Farming does not need to be that way. It's very amenable to electrification.

Long haul aviation needs high energy density.

You have heard critiques about farming that focus on very specific uses of corn and soybean under conventional American agribusiness, and while these are by no means the best biofuel feed stocks or the best harvesting methods, the low ROE is irrelevant if you are willing to feed in arbitrary quantities of cheap solar power to get precious liquid hydrocarbons out.

Flying contributes only 2.5% to global carbon emissions and it is one of the applications where hydrocarbons are least replaceable - bar hydrogen. It is dramatically easier to shift over anything that doesn't have to fight gravity, so flying will likely decarbonize last.

Fertilizer production is dominated (in energy terms) by nitrogen fertilizer, and that's made with hydrogen. Hydrogen would come from electrolysis, and driving that with PV is very likely to be feasible, especially with cheap Chinese electrolysers.

While Ammonia generation "involves just nitrogen and hydrogen", the crux is that it requires high temperature. Haber-Bosch doesn't do at ambient - something like 800°C IIRC. And the heating for such is done by burning something (coal decades ago, gas now).

For many "ordinary" chemicals, the so-called process temperature is the challenge with carbon-free. Not dissimilar from steel or aluminium making (melt the ore first before reducing it).

Haber-Bosch operates at 350-550 C. The energy needed is in compressing the gases, and (at lower pressure) refrigeration to separate ammonia. These are work inputs, and all can be provided by PV generated electricity. At pressure, the ammonia production reaction is exothermic, so ammonia production is a source of heat, not a consumer of heat.

In more detail:

https://www.c-thru.org/wp-content/uploads/2022/12/Ammonia-Te...

"Generally, in the ammonia synthesis loop there is no need for an external heat source because the ammonia synthesis reaction is exothermic. The produced heat from the reaction is a high-valued source which can be recovered to satisfy the temperature requirements of the converter feed-stream and to generate high pressure steam for use in other plant processes. In modern plants, the compressors of the synthesis loop (the syngas/recycle compressors as well as the ammonia refrigeration compressor) are usually centrifugal ones driven by steam turbines which work with the produced steam from the recovered waste heat available within the plant (European Fertilizer Manufacturers’ Association (EFMA), 2000). Overall, electricity consumption values of ~0.32 to ~0.64 kWh/kg-NH3 have been reported in literature for the synthesis loop, depending on the variations in the syngas production pressure, synthesis loop pressure and compression efficiencies (X. Liu et al., 2020)."

Note that the figure given there is an order of magnitude less than the electrical energy needed to make the necessary hydrogen by electrolysis.

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