[acidburnNSA]

I'm in nuclear and I'm super annoyed at the mass hysteria around announcing projects like this using totally unproven reactors.

Just start with a time-honed PWR to decarbonize now and deal with the uncertainty and challenge of MSR development as a potential upgrade for later.

MSRs need tons of development. See ORNL-5018 https://doi.org/10.2172/4227904

[mike_d]

> MSRs need tons of development. See ORNL-5018

I think what you meant to say is the west needs tons of development to catch up.

China already has TMSR-LF1 cleared for startup and expects to be able to start building MSRs for other countries by 2030. Half of all currently under construction reactors are in China, and they have plans for 154 in the next 15 years.

[acidburnNSA]

No, I meant what I said. TMSR-LF1 is a remake of ORNL's MSRE. After MSRE, the experts from that program wrote ORNL-5018 explaining what was needed to come next to commercialize the technology. China's done a great job of rebuilding knowledge needed to run a small reactor experiment. Now the hard work can begin.

[mike_d]

To my point, the United States basically threw in the towel in 1970 despite the director of ORNL calling it the facilities greatest technical achievement. The only reason uranium won out over thorium was because the waste was weapons grade and useful during the cold war. Unlike the US, China has very little in the way of domestic uranium supplies - but incidentally has massive thorium stockpiles from its monazite mining.

I think it is naive to assume that an operation with effectively limitless funding led by the former director of CERN has only managed to clone a 50 year old research project without any advancements. Maybe a better perspective is that that given the strategic value they just aren't sharing the details with the rest of the world.

[acidburnNSA]

> The only reason uranium won out over thorium was because the waste was weapons grade and useful during the cold war.

This is such a common myth that it inspired me to write a whole thorium myths page to explain how and why it's not true, back in 2014: https://whatisnuclear.com/thorium-myths.html#myth1

Happy to discuss more but I've said a lot on that page.

[mike_d]

Absolutely said a lot about the technical and economic justifications, but don't really address the political aspect at all. Remember the that decision was made by the AEC, which at the time was heavily influenced by the Military Liaison Committee. Also forgive me if I don't agree that the people who oversaw unethical human experimentation for 30 years and released radiation over my home town might not have made their decision based on the same sound reasoning you lay out.

If you haven't read it already, Dr. Weinberg's memoir does a good job detailing the politics around the demise of the MSR.

[acidburnNSA]

The decision to shut down the Molten Salt Program within the AEC was driven by Milton Shaw, who also and at the same shut down numerous other programs: sodium graphite program (Hallam), organic program (Piqua), superheat BWR (Bonus, Pathfinder), high temperature gas, etc. He shut these down because he wanted all focus to be on the Fast Breeder Reactor (Clinch River). This was all in 1968.

Uranium-fueled commercial reactors never had anything to do with making plutonium for weapons. Plutonium was made by graphite and heavy water moderated reactors at Hanford and Savannah River.

I have read Weinberg! It's my favorite book. It's interesting that at the end he was more excited about the PIUS PWR than the MSR. Here are my reading notes: https://whatisnuclear.com/weinberg.html