> this must be something with fast cold start. So black/brown coal power plan will not help you, similarly nuclear.

Nuclear plants provide base load and they are extremely fast at ramping up/lowering production. All modern nuclear plants are capable of changing power output at 3-5% of nameplate capacity per minute: https://www.oecd-nea.org/upload/docs/application/pdf/2021-12...

You don't shut down power plants. None of the power plants ever do a "fast cold start"

> The end result now is that electricity in Europe is the most expensive on the World, so all manufacturing is moved to Asia

The production moved to Asia due to extremely cheap labor, not due to electricity costs.

5% per minute is not extremely fast. Simple cycle gas turbine (peaker) plants routinely go 0 to 100% in less than 10 minutes. Nuclear plants can only hit 5% per minute in the 50 to 100% interval (per your own source).

And all of this is confused by the way the nuclear industry uses the term "load following". You'd think it means "changing the power output from moment to moment to match electricity demand" but for nuclear plants it means "changing from one pre-planned constant level to another pre-planned constant level, up to four times per day".[0] There are only three[1] sources of electricity that can be ramped freely enough to exactly match demand: hydro, simple-cycle gas turbines and batteries. All electrical supplies will need some of those three mixed in. Which is why France is still 10% hydro and 10% natural gas in their electricity supply.

0: Some of the most modern Russian plants can move to +-20% of their current target at 10% per minute, but "the number of such very fast power variations is limited, and they are mainly reserved for emergency situations." per your source.

1: OK, there are some obsolete ways too, like diesel generators. At least obsolete at the scale of the electricity grid.

> 5% per minute is not extremely fast.

5% of nameplate capacity.

> You'd think it means "changing the power output from moment to moment to match electricity demand" but for nuclear plants it means "changing from one pre-planned constant level to another pre-planned constant level, up to four times per day"

Which is clearly invalidated by the very source I provided, and which you then somehow quote back at me.

> "the number of such very fast power variations is limited, and they are mainly reserved for emergency situations." per your source.

Imagine if you didn't omit the full quote/context:

--- start quote ---

Also, AES-2006 is capable of fast power modulations with ramps of up to 5% Pr per second (in the interval of ±10% Pr), or power drops of 20% Pr per minute in the interval of 50-100% of the rated power. However, the number of such very fast power variations is limited, and they are mainly reserved for emergency situations.

--- end quote ---

Oh look. What's limited is an actual emergency ramp up of 5% per second or power drops of 20% per minute.

Which is literally an emergency that is not needed in a power grid.

For the foreseeable future, building enough nuclear for peak capacity is exceedingly expensive.

> None of the power plants ever do a "fast cold start"

Somewhere in each grid you will have “black start” capacity contracts, dunno if nuclear can fills this role (or if grids exclude nukes for one reason or another).

Plenty of peaker plants built with the intention of running double digit hours per year and therefore the tradeoff supports being largely “off” in between those calls. Batteries might fill that gap.

> 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:

--- start quote ---

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.

--- end quote ---

> 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...