About 1/5th of US energy usage is renewable. That means we can shutdown 1/5th of nonrenewable plants or shutdown all nonrenewables 1/5th of the time, real answer somewhere in between. The top level post recommends doing this only to carbon sources and leaving nuclear alone.

There are good arguments for and against pivoting to nuclear right now. But there is an (I think) unquestionable position presented here that we shouldn't be pivoting away from nuclear and shutting down plants.