Energy storage solves that problem. The technology exists, the only potential trouble is cost, so it comes back to price again. Storage costs are also dropping rapidly. A proper comparison of nuclear to wind/solar needs to account for the cost of storage as well, but even if you add that in I suspect it's approaching parity.
I'm puzzled as to why you quote part of my comment and then act like I didn't think of the point you're making, when I made the exact opposite point just one sentence later.
Batteries, pumped hydro, thermal storage, and many other technologies exist. They just need to become cheap enough. Thus, the problem is once again price.
It's not just price. None of the technologies you mention scale to anywhere near the levels of a nuclear powerplant. It's a huge engineering issue that, while most likely solvable, simply hasn't been solved yet.
How so? Pretty much any building you can point at has enough space for batteries to sustain its power needs overnight. The only reason we haven't all run out and done it is because, first, it's not necessary with the grid as it is now, and second, it costs a whole lot.
The engineering issues are in getting this stuff to be sufficiently cost effective that we can afford to put them into wide use.
How many batteries can we build? How do we build them on such a large scale? Do we mine enough raw materials for so many batteries? Are there enough materials for so many batteries? How do we cool them? How do we replace the faulty ones? How long do they last? How many people do we need to maintain them? How do we train them? How do we dispose of the batteries?
Not all of these questions have have hard or problematic answers (e.g. especially the last one is probably much worse for nuclear), but they do need to be answered, at all. We've been answering these questions for nuclear for the past 50 years.
They are currently being used in Africa and South America primarily for industry use (telecommunications mostly).
No, you won't run an aluminium smelter with them, but for load balancing during those (pretty rare!) times when you don't have either solar or wind they are fine.
I don't know about the temperature problem. I know they are used here in Australia at 40C+ and in Africa in similar climates.
I think that they are actually better for industrial use than home use. They aren't silent, and they need to be cycled. The noise isn't an issue in industry, and in home use I know the power cycling can sometimes be a problem because it is hard to find somewhere to dump the power (currently the solution is to dump it to heat, which isn't great - or alert the homeowner and get them to run a pool pump or something).
