[pfdietz]

DT fusion looks bad even if you totally ignore anything related to plasma physics or magnetic fields. Simply handling the heat flow and neutrons from the reactor looks to make the reactor too big to compete, compared to fission reactors.

And then you have the problem of having to stick sophisticated stuff in the hot zone where hands-on maintenance is impossible (compared to a fission reactor, where just the fuel and relatively simple hardware is in that zone.)

[gfodor]

Fusion doesn’t have the stigma of fission, or a lot of the risks, and so if we can get to a point where we are actually building new fusion reactors, we should assume the technology will improve rapidly.

[pfdietz]

It's a common error to think that fission power plants aren't being built because of "stigma". The actual problem is failed economics. Fusion promises to be even more expensive, for the reasons I explained.

It's not clear why one should expect fusion to have good experience effects. Fission didn't, and the non-nuclear parts of fusion power plants will be mature technologies.

[gfodor]

Your argument is that the stigma of nuclear meltdowns hasn’t impeded the deployment of nuclear energy?

[pfdietz]

If reactors were ten times safer but no cheaper, they still wouldn't be being built.

If reactors were ten times cheaper but no safer, we'd be building them like hotcakes.

[lwouis]

I think Japan disabling their fission plants after Fukushima, and Germany following that path are clear manifestation of the opposite: that people fear nuclear and democratic governments act on this fear, against development of the technology.

[nickik]

While this is true, its a fact that the regulatory and governmental outlook on fission has prevented these changes from happening.

The western world has made development of new fission plants practically impossible. Requiring 100s of millions in development before you might get a hint if the government would actually allow you to build a plant.

Thankfully this has finally started to change. Mostly in Canada and that's where we will likely see next generation fission first.

[pfdietz]

Regulation is the scapegoat for nuclear's failure, but it's equally the case that regulation is vital to nuclear (and to nuclear getting liability caps.) If the risk of nuclear were not socialized no one would build it (or insure it).

What has also prevented changes from happening is that nuclear scales down poorly, so the cost of iterating designs is so large. Making a new kind of PV cell or module, or wind turbine, is comparatively much cheaper, because these are individually much smaller and cheaper. The replicated nature of these sources is an advantage in so many ways.