3 ms·

I'm a civil engineer, and let me just say I'm extremely skeptical of several of these: I doubt that there's ever going to be superconductors used commonly in l

I'm a civil engineer, and let me just say I'm extremely skeptical of several of these: I doubt that there's ever going to be superconductors used commonly in long range power transmission. The economics just won't make sense, the conductive properties of the material are not the only ones that matter: (lifespan, toughness, flexibility, etc. matter a LOT.) Fusion reactors will be a lot easier to construct when you don't need such ridiculous cooling needs, but I still don't get why we don't just build more fission reactors. They work great, and we could have been carbon neutral decades ago. You think fusion reactors will solve the construction cost problem? Imaging and other sensors I think will be huge. Man, mag lev trains aren't ubiquitous in the states because of the cost of running them. They are just almost impossible to build in the present political climate where the extreme cost of right-of-way acquisition through eminent domain needs and environmental regulation and litigation come into play. It's already way too expensive to just build roads out of rock. No way we replace roads with magnetic rails.

pfdietz 3y ago
> You think fusion reactors will solve the construction cost problem? I don't think DT reactors will solve this problem. If anything, they will make it worse. The volumetric power density of a DT fusion reactor is going to be at least an order of magnitude worse than a fission reactor, for fundamental reasons involving limits on heat transfer across surfaces. This is why people are excited about Helion, which sidesteps the problem by extracting energy from the plasma electromagnetically rather than as heat (heat is still dissipated, but it does not have to be run through a heat engine.) BTW, for transmission, superconductors would be more interesting for buried power lines, where voltage is limited and heat dissipation is problematic. Sueprconductors are also interesting in aerospace, particularly for hybrid electric aircraft.

pfdietz 3y ago

> You think fusion reactors will solve the construction cost problem? I don't think DT reactors will solve this problem. If anything, they will make it worse. The volumetric power density of a DT fusion reactor is going to be at least an order of magnitude worse than a fission reactor, for fundamental reasons involving limits on heat transfer across surfaces. This is why people are excited about Helion, which sidesteps the problem by extracting energy from the plasma electromagnetically rather than as heat (heat is still dissipated, but it does not have to be run through a heat engine.) BTW, for transmission, superconductors would be more interesting for buried power lines, where voltage is limited and heat dissipation is problematic. Sueprconductors are also interesting in aerospace, particularly for hybrid electric aircraft.