It depends what you call fast. It's my understanding that PWR's like this ramp from 50% to 90% in about an hour.
But nuclear power plants have a huge capital cost, so you really don't want them to operate for half of the day at 40% or they're even more expensive for the power generated.
And going below a minimum output power means a long time to get power back, which is why in North America power prices sometimes go negative (don't want to shut down).
But nuclear power plants have a huge capital cost, so you really don't want them to operate for half of the day at 40% or they're even more expensive for the power generated.
And going below a minimum output power means a long time to get power back, which is why in North America power prices sometimes go negative (don't want to shut down).