[raphlinus]

Amen. When someone does the math and adds up the winners and losers in all this, one clear winner will be this video from Asianometry, entitled The History of Superconductors (Before LK-99)[1]. It only lightly touched on LK-99 itself, but did an excellent job going through the actual science-based history of superconductors, covering in particular detail previous hype waves. A major point is that the YBCO superconductors, while an amazing scientific discovery, haven't had revolutionary applications, and have only lightly displaced lower temperature (niobium-titanium metal alloy) superconductors in applications requiring generating strong magnetic fields, including MRI machines. For the curious, [2] goes into considerable detail on potential applications and challenges for HTSC in MRI.

[1]: https://www.youtube.com/watch?v=wUczYHyOhLM

[2]: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5472374/

[DennisP]

REBCO is revolutionizing fusion reactors. Several companies are using it to build tokamaks with the same performance as ITER, but in a tenth the size.

REBCO supports stronger magnetic fields, and conveniently, tokamak output scales with the fourth power of magnetic field strength.

[pfdietz]

> same performance as ITER, but in a tenth the size

So instead of being 400 times the volume of a PWR with the same gross power output, they're just 40 times the volume. It's no panacea to the economic challenges facing fusion.

The other way to get high volumetric power density is go with a configuration of higher beta, the ratio of plasma pressure to magnetic pressure (fusion power at a given magnetic field scales as beta^2). Helion isn't using superconductors at all.

[u320]

REBCO was a bigger deal for fusion than LK99 would have been. We can't make tokamaks smaller, the magnetic forces would rip them apart.