> Nuclear plants provide base load and they are extremely fast at ramping up/lowering production
The obvious counterexample is Chernobyl, where a big contributor was the fact that they were unable to scale it down & back up as desired. Yes, nuclear reactors can scale down rapidly - but you have to wait several hours until it can scale back up!
Besides, the linked paper only covers load-following in a traditional grid (swinging between 60% and 100% once a day) and barely touches on the economic effects. The situation is going to look drastically different for a renewables-first grid, where additional sources are needed for at most a few hours a day, for a few months per year.
> You don't shut down power plants. None of the power plants ever do a "fast cold start"
Gas turbines can. Hydro can. Battery storage can.
The answer is you don't scale nuclear up or down, it's a silly waste of time and effort to even think about it. The fuel costs are effectively a rounding error, so running at 100% 24x7 is the only way to ever think about how nuclear should operate.
If you are going to curtail, you curtail other sources including solar and wind.
Nuclear fits quite well for the baseload you need. It's more expensive, but if you are going to need X capacity 24x7 and build nuclear, you simply build enough to provide just that plus perhaps a few extra for redundancy when another one goes offline. Then use gas peakers for the "oh shit" days difference between what nuclear is providing and solar was expected to but could not.
I don't understand the fascination folks have about nuclear not being able to following the grid. They don't need to, since they only ever remotely make sense when operated 24x7 at 100%. If you always have 1TW of grid usage every night during your lowest usage period - build that much nuclear as your starting point and figure out the rest from there. Nuclear's share of the total mix should be a straight line on a graph outside of plant shutdowns for maintenance.
> The obvious counterexample is Chernobyl,
You mean the obsolete design that is not used even in old reactors, not to say of modern designs?
Quote:
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The minimum requirements for the manoeuvrability capabilities of modern reactors are defined by the utilities requirements that are based on the requirements of the grid operators. For example, according to the current version of the European Utilities Requirements (EUR) the NPP must at least be capable of daily load cycling operation between 50% and 100 % of its rated power Pr, with a rate of change of electric output of 3-5% of Pr per minute.
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> The situation is going to look drastically different for a renewables-first grid, where additional sources are needed for at most a few hours a day, for a few months per year.
Ah, to live in these mythical times...