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We have basically limitless carbon free energy with the tech we have now: solar, wind, batteries, fission breeders, large power grids that can move power around cheaply, etc. Put all those together and we have incredible energy abundance.

We also have the ability to electrify most transport except maybe long haul trucking and long haul aviation. Aviation (ALL aviation) accounts for less than 5% of global CO2 emissions, which means we could leave that alone and cut elsewhere until we have batteries and other infrastructure good enough for that.

Build all this out and it'll be cheaper and more scalable than what we currently have.

We in the USA choose to stick with ancient technology because we have a sunk cost and an existing political power structure built around it. Meanwhile China is eating our lunch. Make America Great Again! By... pretending it's 1945 and trying to LARP the previous century.

Classic innovators' dilemma at the national level.

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I'd love to see as much electrification as possible.

On the aviation note, sadly, aviation bats higher than its C02 accounting. Contrails add another 1-2% on top of contribution from it's C02 emissions. It's entirely avoidable and could be resolved at relatively low cost.

https://contrails.org/faq/#how-are-contrails-contributing-to...

If that’s the case it makes aviation like 6-7%, still low. Coal fired electricity generation is king when it comes to climate change, followed by oil fueled land transport and natural gas. Deforestation is higher too. Aviation is part of the long tail.

If grid energy was cheap enough, synthetic fuel for aircraft and trucks would be competitive.

Nope, you can't make synthetic fuel at anywhere near a competitive price from electricity. To make a synthetic fuel, the major energy input is heat (yes I know, you use electrolysis to crack the water, its a minor part of the energy required). The only way to make a cheap synthetic fuel is from a nuclear reactor that produces heat in the 900C range (could be 700C or 1100C, but near there). You can't do that with solid fuel reactors, you need a liquid fueled reactor for that. And you need Thorium for a liquid fueled reactor. That's why this design is so popular.

> The only way to make a cheap synthetic fuel is from a nuclear reactor that produces heat in the 900C range (could be 700C or 1100C, but near there). You can't do that with solid fuel reactors, you need a liquid fueled reactor for that

Some of the highest temperature reactor concepts use solid fuel (see e.g. various VHTR gen4 concepts).

As an aside, some nuclear proponents claiming synthetic fuel production as some unique selling point of advanced nuclear sounds more like wishful thinking combined with admitting being unable to produce electricity at competitive price. With the 'electrotech revolution', most things will switch to being powered by electricity, leaving a relatively modest market for synthetic fuels (long range aviation and shipping, mainly, and some chemicals production), assuming regulation prevents usage of fossil fuels.

> And you need Thorium for a liquid fueled reactor.

No, why would you? You can use U235 in a non-breeding thermal reactor (Terrestrial being an example design), or you can run the U-Pu breeding cycle in a liquid fueled fast reactor (such designs use chloride salts as the fuel carrier rather than FLiBe).

> That's why this design is so popular.

So popular that despite being invented in the 1960'ies, it hasn't yet progressed beyond the prototype stage?

> We in the USA choose to stick with ancient technology because we have a sunk cost and an existing political power structure built around it.

You don't want to discount the cultural attachment people have to what their parents did and their childhood.

> We in the USA choose to stick with ancient technology because we have a sunk cost and an existing political power structure built around it.

Yes, and also vast oil and gas reserves China doesn't have.

Also there is strong public fear and dislike of nuclear power.

In countries where there are no or little fossil fuels it is mainly this public opinion which has crippled the nuclear industry. Germany is a prime example.

Public opinion is obviously much less important in China.

> Public opinion is obviously much less important in China.

That really isn’t true. The reason Shanghai didn’t expand their maglev to Hangzhou is because residents were worried about electrical magnetic radiation, which I don’t think is really a thing. Nuclear took a long time to get started in China because people thought the government to be inept and corrupt, an image that has only recently faded away in the last decade. Without free elections, public opinion is actually much more important if you want to avoid economically destructive riots.

But this all happens in back rooms, the legal system isn’t very relevant, so if you have an issue but it isn’t a very popular one, you don’t really have any recourse. For example, niche environmental issues, or ones that aren’t widely recognized yet as dangerous…

Public opinion here appears to count for nearly jack squat so I don’t buy this explanation at all.

FF extraction is very profitable and has been for a long time. Those that make money from extraction spend a lot on lobbying. They don't want nuclear power because its the only thing that can really replace FFs. The public opinion angle is just useful idiots being manipulated by people who make money from FF extraction. That makes it far easier to get the politicians to do what they want (kill nuclear).

fossil fuel also underpins the us dollar so there’s that too

"Public opinion is obviously much less important in China."

In the US public opinion doesn't really matter either. It's the oligarchs' opinions that matter

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