Bad phrasing on my part. Wind/solar/nuclear are all basically pure capex with no marginal cost to producing max energy so they all need to be run at 100%.

To handle daily/seasonal energy demands though, you'll want to run any of those all the time and thus dump surplus energy into some type of storage to reduce capex costs and dynamically handle demand with some type of peaker.

So your options are nuclear surplus + storage or wind/solar surplus + storage but why light your money on fire with nuclear creating said storage when wind/solar are 1/3 the cost.