[patientplatypus]

Yeah, except...your Australian idea of putting massive power plants in the Outback and de-carbonizing the atmosphere by shipping fossil fuels into the atmosphere is incredibly inefficient. Just put in small scale nuclear power plants at all the limiting bandwidth areas of every nations' power grids. From there electricity would be essentially be free and you could power cars, trains, buses and everything else from electricity. You could have nuclear powered cargo container vessels. There wouldn't be any need for coal or oil. Why do half measures that would be worse for the environment, when you could just stop using goal and gas entirely? By the time all of the useful plutonium and uranium runs out for making power plants we'll have fusion power (within the next 100-200 years). You're not wrong, and the market may mandate doing this anyway, but if you were going to play benevolent dictator and find the most utilitarian way to maximize the world's happiness you would just make energy free.

[fwlr]

Unfortunately we cannot simply play dictator and insist people who don’t like or trust nuclear power must put up with “a Chernobyl next door to every school” (or similar charged rhetoric). The Outback is one of the few places I can imagine just enough people tolerating for it to happen, where there’s also enough infrastructure and capability to keep it running. The fact that Australia also has the largest reserves of nuclear fuel in the world and a significant investment in mining capability certainly doesn’t hurt either.

So that’s kinda where it has to be. Once it’s there, how do you make it affect the rest of the world? The longest HVDC cable in operation is 750km at 1.4GW, and the longest being built is 4 x 3,800km cables at 1.8GW each. The undersea internet cable that connects Australia to America goes through Hawaii and is 14,000km long. And you need to get something like 60GW through to power the western region of the US grid, even assuming big advances it’s still like 12 x 14,000km. Impractical. You need to make it transportable. Batteries don’t have energy density to make it work shipping them en masse, especially since they need a return trip. You know what does have high enough energy density to make it worth transporting? Coal and oil, we already do it. Added benefit: it’s a drop-in replacement for existing power systems, no need to rebuild any power systems anywhere. How can we turn nuclear power into coal and oil? Carbon capture synthesis of hydrocarbons. Another added bonus: fights climate change.

The previous two bonuses synergise immensely well: they take existing ICE engines and coal power plants and make them zero emissions. The drawback of inefficiency sucks, but it’s more than outweighed by all those benefits. I’m not trying to use nuclear as efficiently as possible. I’m trying to find a place for nuclear in the energy economy.