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0 pointssehansen16d ago0 comments

Gas turbines do 16% of nameplate capacity per minute without catching a sweat. 5% per minute isn't particularly extreme.

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Let me quote page 10 of your source "In brief, most of the modern light water nuclear reactors are capable (by design) to operate in a load following mode, i.e. to change their power level once or twice per day in the range of 100% to 50% (or even lower) of the rated power, with a ramp rate of up to 5% (or even more) of rated power per minute". Your own source defines "load following" as changing the targeted power level once or twice per day.

Again on page 14 (about how the French currently run their nuclear plants): "The nuclear power plants operating in the load following mode follow a variable load programme with one or two power changes per period of 24 h". Weirdly enough this is contradicted by table 2.1 on page 20 where they do four changes per day.

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

If you look at table 2.4 on the same page it states that it (the Russian VVER-1200) can do the 5% per second/20% per minute emergency change 20 000 times over the lifetime of the reactor. The 10% per minute change can also only be done 20 000 times over the lifetime of the reactor. Table 2.2 on page 21 helpfully calculates that 15 000 cycles is once per day for 40 years, so the VVER-1200 only can do a bit more than one >5% change per day (outside of emergencies) assuming a similar 40 year lifespan. And that was the point of my footnote: that nuclear plants technically can go faster than 5% but not up and down on a minute-by-minute basis.

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troupo15d ago

> Gas turbines do 16% of nameplate capacity per minute without catching a sweat. 5% per minute isn't particularly extreme.

If you keep jumping around with your arguments, nothing is extreme.

Your original claim started with claiming cold starts (which most power plants including gas turbines don't do, ever) and that coal and nuclear aren't fast.

Nuclear is plenty fast.

I never claimed gas power stations were slow, or that they were slower than nuclear.

> If you look at table 2.4 on the same page it states that it (the Russian VVER-1200) can do the 5% per second/20% per minute emergency change

Let me slowly walk you through that statement:

--- start quote ---

can do the 5% per second/20% per minute emergency change

emergency change

emergency

--- end quote ---

> And that was the point of my footnote: that nuclear plants technically can go faster than 5% but not up and down on a minute-by-minute basis.

No idea what your footnote was about, and how it is relevant.

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