I'm not claiming that renewables have to completely replace fossil fuels (see my reference to carbon capture), or that they even need to be cheaper (fossil fuels could become artificially expensive by, eg, carbon taxes). I'm questioning the assertion that nuclear is essential, which is what was claimed by the comment I replied to.

Nuclear might be nice to have, might be better for various reasons, might be lots of things. But is it absolutely required "to solve the looming energy crisis of the 21st century while still maintaining the same standard of living for everyone"? That's my question.