> Make a nuclear power plant factory and you can get those numbers way down.
Except we’ve never done that so we don’t know how big a scale we’d need to get costs down. In the absence of evidence, it’s entirely conceivable there isn’t enough economically recoverable uranium in the world for mass production of reactors to be cost effective.
Therefore the only cost estimate we can rely on is what we have actually managed thus far.
> Finally, cost probably isn't the right way to look at it. The issue at hand is mostly efficiency, where obviously the nuclear option wins handily.
I disagree with both of these claims. For the first: for most of my life, the argument against green power, the reason nothing changed, was always the cost. Make the solution cheap and the problem goes away all by itself.
For the second: so long as it is energy positive (EROI>>1, true for both), and the cost per unit is low (which you’re already dismissing), and you’re not resource constrained (we aren’t), I can’t see what other measure of efficiency matters much. The light-flux to electricity conversion efficiency? No more important than thermodynamic limits in a reactor heat engine. Resistive losses in transmission? I’ve just demonstrated that is irrelevant.