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by MagnumOpus 1595 days ago
> gas power plants can be switched on and off very quickly at peak times (in strong contrast btw to nuclear power plants)

Not true - from the wiki: Modern nuclear plants with light water reactors are designed to have maneuvering capabilities in the 30-100% range with 5%/minute slope, up to 140 MW/minute. Nuclear power plants in France and in Germany operate in load-following mode and so participate in the primary and secondary frequency control.

https://en.wikipedia.org/wiki/Load-following_power_plant
2 comments
natmaka 1595 days ago
A nuclear reactor can only do this (depending upon combustible bars state) at most twice per day. This is a severe limitation. France is a leader in this field. Source (French language ahead!): https://new.sfen.org/rgn/expertise-nucleaire-francaise-suivi...
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Archelaos 1595 days ago
Gas plants have a possible rate of change of aprox. 20%/minute. Admittedly, it may be a matter of taste whether a fourfold rate might be called a "strong" contrast. So let's just say that the rate of change of gas plants is typically four times higher.

Besides, the actual rates of change for nuclear power plants vary widely, depending on the current load of the power plant. According to the German Wikipedia the actual capabilities of (former) nuclear power plants in Germany ranged from 1.1% to 10% per minute. When the plant was below 50% of its load, the possible rate was near the lower end of this spectrum. The maximum of 10% was only possible when the plant was already running above of 80% of their nominal power. The value was also very much dependent on the operating state of the plant.[1] So the 5%/minute you mentioned are just an average.

Historically, nuclear power plants have been used as load following plants in Germany, but this was during times, when the overall volatility of power production was lower than today. And when it comes to new nuclear power plants currently being planned elsewhere, their load following capabilities are to my knowledge typically an afterthought.

[1] https://de.wikipedia.org/wiki/Lastfolgebetrieb#Kraftwerkstyp https://de.wikipedia.org/wiki/Druckwasserreaktor#Lastfolgebe... https://de.wikipedia.org/wiki/Siedewasserreaktor#Lastfolgebe...

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