[pfdietz]

Nuclear would be utterly terrible for filling in the last part of a renewable-dominated grid. As in, ludicrously expensive, compared to other non-nuclear, non-fossil alternatives.

The article you point to talks about "firm, low carbon sources". This kind of source for this last bit would be something like hydrogen, not nuclear. A nuclear reactor operating at 10% capacity factor to "fill in" for renewables would be producing power at $1/kWh or more, which is uncompetitive vs. hydrogen by a massive margin.

[dTal]

You can invert this and say that solar/wind would be utterly terrible at "filling in the last part" of a nuclear-dominated grid.

The inability to generate constant, reliable power is a weakness, not a strength.

[pfdietz]

Right. It's one or the other generally (although some solar could help nuclear if demand peaks on sunny days).

However, unless nuclear gets a lot cheaper, it's looking like the nuclear dominated grid is going to be more expensive than the renewable dominated grid, even taking the cost of intermittency into account.

[DennisP]

They specifically cited nuclear. I don't think operating it at 10% capacity factor is what they mean.

[pfdietz]

They very carefully didn't mention hydrogen at all. They compared nuclear vs. renewables + batteries. It's almost as if they were setting up renewables to fail. Imagine that, in a study where half the authors are from the Department of Nuclear Science and Engineering.

Yes, if you had nuclear, you'd operate it at high capacity factor. That isn't nuclear filling in for renewables, that's using nuclear instead of renewables. It's really mostly one or the other.