Fusion Reaction

[Reality Check]

I think we will see commercially viable thorium molten salt reactors well before fusion. China was supposed to start up a 2 MW pilot reactor last year. Other countries are going forward with various designs.

[keith]

I think we will see commercially viable thorium molten salt reactors well before fusion. China was supposed to start up a 2 MW pilot reactor last year. Other countries are going forward with various designs.

Yeah. That goes without saying.

Thorium reactors have been around since the 1960's.

Fusion reactors are still 10 years away (and have been so for the last 70 years and will probably be so for the next 50 years),

[neeneko]

Eh, I actually kinda see thorium reactors in a similar way to fusion reactors. Both have been around for a long time, and both are the big hope to finally create cheap limitless energy, and a viable design is always right around the corner. Both, on paper, are great ideas and should work, but neither has sorted out the engineering challenges.

[Reality Check]

Yeah. That goes without saying.

Thorium reactors have been around since the 1960's. Yes and no. In the 1960's Oak Ridge ran a molten salt reactor successfully for 4 years fueled with uranium-233. The project was closed and the technology was abandoned. Most accounts say the AEC wanted to pursue the fast breeder reactor instead largely because a by product was weapons grade uranium. The fast breeder reactor never panned out. Thorium was only revived as a technology in the 2000's by NASA scientist Kirk Sorensen who was looking at how a moon base could be powered and rediscovered thorium.

Fusion reactors are still 10 years away (and have been so for the last 70 years and will probably be so for the next 50 years), No argument from me there.

Eh, I actually kinda see thorium reactors in a similar way to fusion reactors. Both have been around for a long time, and both are the big hope to finally create cheap limitless energy, and a viable design is always right around the corner. Both, on paper, are great ideas and should work, but neither has sorted out the engineering challenges. I don't think Thorium MSR's and fusion are as comparable as you make them out to be. As I mentioned above thorium research was abandoned in 1969 for almost 40 years. Meanwhile something like $30 to $50 billion has been spent on fusion with reactors barely reaching the break even point. I could not find the amount spent on thorium reactors but it has to be orders of magnitude less than fusion.

The development on thorium and MSR's is mostly being done by for profit companies with little funding from the government at least in the US.

Commercially viable thorium reactors are probably less than a decade out. I doubt anyone would predict that for fusion.

[neeneko]

Commercially viable thorium reactors are probably less than a decade out. I doubt anyone would predict that for fusion.

It would actually not surprise me if commercially viable thorium reactors do get developed, and I agree the comparison is rather differnt in scale. But I've been kinda rubbernecking the thorium-evangalist community ever since that first google talk that popularized them and it reminds me a lot of the strong AI and fusion communities in its rather 'eveyone knows it is right around the corner' optimism. It has become a repository for people's hopes and dreams, a fix all solution that will end the whole 'energy' and 'environment' problem being pioneered by the next generation of Musks, and the only reason it might fail is 'the government' or 'environmentalists'. I generally do not see nukees singing its praises, but it is another tech-bro darling... though to its credit, it is at least one that is a solution that has a solid problem it addresses,... so a bit more bleed into the wider culture.

[Suranis]

https://www.livescience.com/physics-mat ... r-15-years

livescience.com
World's largest nuclear fusion reactor is finally completed. But it wont run for another 15 years.

ITER, a $28 billion fusion reactor in France, has finally had its last magnetic coil installed. But the reactor itself won't fire up fully until 2039 at the earliest.

[RTH10260]

further explanation

ITER fusion reactor hit by massive decade-long delay and €5bn price hike

03 Jul 2024
Michael Banks

The ITER fusion reactor currently being built in France will not achieve first operation until 2034 – almost a decade later than previously planned and some 50 years after the project was first conceived in 1985. The decision by ITER management to take another 10 years constructing the machine means that the first experiments using “burning” fusion fuel – a mixture of deuterium and tritium (D–T) – will now have to wait until 2039. The new “baseline” was agreed as a “working reference” by ITER’s governing council and will be further examined before a meeting in November.

ITER is an experimental fusion reactor that is currently being built in Cadarache, France, about 70 km north-west of Marseille. Expected to cost tens of billions of euros, it is a collaboration between China, Europe, India, Japan, Korea, Russia and the US. Its main aim is to generate about 500 MW of fusion power over 400 seconds using a plasma heating of 50 MW, a power gain of 10. The reactor would also test a “steady state” operation under a power gain of five.

Yet since its conception in the 1980s (see timeline below), ITER has been beset with cost hikes and delays. In 2016, a baseline was presented in which the first deuterium plasma would be delayed until 2025.

This first plasma, however, would have been a brief machine test before further assembly, such as adding a divertor heat-exhaust system and further shielding. “The first plasma [in 2025] was rather symbolic,” claims ITER director-general Pietro Barabaschi, who took up the position in October 2022 following the death of former ITER director general Bernard Bigot.

ITER would only have reached full plasma current in 2032 with the first D–T reaction waiting until 2035 after the installation of additional components.

A new ‘baseline’

Barabaschi notes that since 2020 it was “clear” that the 2025 “first plasma” date was no longer achievable. This was due to several reasons, one of which was the COVID-19 pandemic, which led to supply-chain and quality-control delays.

Manufacturing issues also emerged such as the discovery of cracks in the water pipes that cool the thermal shields. In early 2022 the French Nuclear Safety Authority briefly halted assembly due to concerns over radiological shielding.

Officials then began working on a more realistic timeline for construction to allow for more testing of certain components such as the huge D-shaped toroidal-field coils that will be used to confine the plasma.

The plan now is to start operation in 2034 with a deuterium-only plasma but with more systems in place as compared to the previous “first plasma” baseline of 2025. Research on the tokamak would then be carried out for just over two years before the machine reaches full plasma current operation in 2036. The reactor would then shut down for further assembly to prepare for D-T operation, which is now expected to begin in 2039.



https://physicsworld.com/a/iter-fusion- ... rice-hike/