pbmonster

As long as you have well suited oil/gas wells to put compressed CO2 into, you'd much rather do that.

DAC of a ton of CO2 costs around ~2 MWh. Compressing it into a well costs ~0.5 MWh, but low temperature reduction to solid graphite costs ~10 MWh.

Solid storage in soil is much more interesting in bio char applications, because the char is full of nutrients and a good water absorber.

Of course, direct air capture of CO2 is extremely energy intense. You can only do it if you've built excessive renewable energy overproduction. And I mean unimaginable excessive.

We've emitted more than a trillion tons of CO2 since 1990. If we want to put just that back into the ground (pump it into old oil wells), the final storage will be several thousand cubic kilometers of high pressure CO2. Just the direct air capture will cost more than an Exawatt hour of renewable electricity (currently, humanity produces around 30 PWh of electricity per year from all sources).

You can use some tricks. Turning all agricultural waste, forestry waste and organic garbage into bio char (instead of letting it decompose on the fields or in compost facilities, which emits CO2) captures a few billion tons per year, but that's far more labor intense and requires a lot of automation work.

Not a massive hurdle. BMW got the i3 to be street legal in the US without much trouble. And I know, the i3 was only a smaller car, it wasn't a cheap car (I think they went for around $40k new)... but that's just BWM.

Getting Renault e-Twingo / Citroen e-C3 street legal in the US wouldn't really rise the production cost much. But nobody is going through all the trouble, because (obviously) almost no American would buy such a car, even though they start at <$20k new.

> For solar, seasonality would be best addressed by thermal storage

Still, adds a lot of cost and complexity onto cheap solar + 12h of chemical battery storage.

> This is being pursued most interestingly by Standard Thermal's "hot dirt" approach.

Pity they want to do only 400°C. Because once you go towards firebricks and >700°C, you can run practically all thermal chemical processes in a refinery or a polymer plant off the heat, and you can make electricity with a supercritical CO2 turbine at >50% efficiency (in a comparatively tiny package). At the cost of much harder engineering problems, of course.

But its probably worth solving those, because you can do interesting stuff with ultra low cost hot gas. Preheat the charge for a steel mill, design a Hall–Héroult aluminium smelter that keeps the electrolyte bath molten via a gas heat exchanger instead of electricity, ect.

And once you have several GW of guaranteed heat consumers, adding a couple of CO2 peaker turbines isn't such a big leap anymore.

I always wish maps like that would include some sort of seasonality score. Maybe a worst week / best week ratio.

As it is, the map is useful until solar goes to a double digit percentage of total yearly generation. Any higher, and seasonal places start needing backup generation capacity that is only running in winter (or during monsoon), which does violent things to electricity markets.

No, that's the Sichuan Basin. The climate is subtropical with monsoonal rain all summer and dry and cloudy winters. It basically has persistent cloud cover all year and heavy fog. Less than 30 days of sun per year.

> Micro and nanoplastics are also a problem that urgently needs to be addressed.

Bio-plastics won't do this automatically. You can make today's polymers from biomass feedstock. Those will have the exact same micro/nano plastic problems.

You can also make polymeres, that are much more bio-degradable, with the associated particulate matter decaying instead of accumulating forever - but you could make those from crude oil just as well, and those degradable polymeres bring an entirely different zoo of problems with them.

> Mercedes is certainly one of them which has lost it's "our engines are nicer" brand

Mercedes is doing something interesting with its level 3 DRIVE PILOT. As far as I know, it's the only autonomous driving system/auto pilot on the market that actually takes full legal responsibility for the vehicle and its actions. If you put a new Mercedes in self driving and it crashes, Mercedes takes full liability.

Yes, it currently only goes up to 100 kph and it will buzz you to take over if it can't guarantee prefect safety anymore. But this approach is really the only one I think is interesting. All this self driving shit is worthless to me if I'm still liable in the end. So I respect Mercedes for putting their money where their mouth is.

How did you get that number? Is this just a quip about batteries?

Most of India has a solar capacity factor >0.2 and low seasonality. That means even 5kW peak rooftop panels and a 10 kWh battery will get you over 95% almost always. And panels+labor is so cheap in India, there's really no reason not to just tile the roof in panels.

Things get more difficult in dense cities, if you have multi story apartment blocks going 90+% locally is impossible. But then just transmit power from lower density rooftops, or actual solar farms.

And this already assumes widespread AC (really no way to increase electrification this much and not add AC in that climate).

> "that's on me, I'm owning that, I'm sorry, that shouldn't have happened"

Does it auto-update now? I like its UI better than PipePipe, but I got so sick of hand-updating Vanced (including hand-downloading the correct apk and waiting several minutes for the patches to run against it) every time Google breaks Youtube again. There was a period of Warfare last year where Google would make breaking changes more than once a week...

PipePipe is so nice with the fast auto-updates. If I ever even catch it breaking, I just have to use Firefox for a few hours and then F-Droid ships the fix and PipePipe works again.

But you would need maglev if you wanted to compete on energy per ton of cargo per mile. Ships are several times more efficient than classic trains.

> At 2% of sales, the opportunity cost is the reason to kill the product. Keep in mind this still needs design, manufacturing, marketing, and distribution resources.

All this is true for many other products, specifically cars. Ford makes the Bronco Sport anyway, and they make money on it.

I get it, Apple has much better margins than Ford. And maybe a iPhone 18 Mini would reduce total margin for them. But if they move a couple of million units, it absolutely would make money.

> enough ammonia in the air will suffocate you.

It will suffocate you on account of all that blood pulp in your lungs. And eyes, and nasal mucosa...

Having a high pressure ammonia leak indoors is a death sentence for anybody in the same room. Same building, if it's large enough...

Technically, you could also just pull refrigerant lines from the heat pump to the bath tub - you probably already run those to the indoor AC units you have in different rooms anyway - or connect the bath tub to the hot water lines you run to the radiators. Both imply a grey water heat exchanger built into the tub.

Depends on setup, of course. If there's a central AC blowing hot/cold air through ducts, you're stuck using a grey water loop. But it is the least attractive setup...