The only fair way to compare the cost to solar and wind, is if wind and solar producers would have to make power guarantees 24/7 and cover the cost of the production gaps (hint: this makes solar and wind very expensive).
The UK is a grid that is adding lots of renewables and building some nuclear plants, so the site provides good data around the costs for the added transmission, storage and subsidies (for both renewables and nuclear) needed for a renewables heavy grid supplemented with nuclear.
* Forecast cost for 2030: https://www.electricitybills.uk/2030
* Source data is here https://docs.google.com/spreadsheets/d/1SHuFAtxxKUf3Q2b7usoT...
Those plants are not designed to be turned on and off, and both must be done gradually and carefully to avoid cracking the turbines.
A decent bunch of that is going to be sheer inertia as you have to spin up a heavy chunk of metal. Keep that rotating (which is actually a good thing in renewable-heavy grids!) and it can be done even faster. Similarly, keeping some parts warm costs very little energy and allows even faster ramp=up.
But that's actually not relevant because battery storage is far more attractive for that kind of short-term demand. The renewable grid will need gas plants which can fill in the gap left when it is both dark and wind-less - which due to meteorology is trivially known 72 hours in advance, leaving plenty of time to prepare the plant for use.