Hahaha....anyone who references Wiki to back up their arguments, really needs to reconsider their sources!
not really, I was using it deliberately to make the point that it should be common knowledge for anyone with half a clue about the UK electrical supply industry if even wikipedia has a decent article about it.
In France at 4am on the Thursday night, demand fell to 39GW, but they were still generating 48GW, 44GW of which was from Nuclear. At 8am demand has risen to 55GW, and nuclear has risen to 47GW.
So even after all their economy 7 night storage heater efforts, their demand fluctuates by around 30%, but nuclear can only fluctuate by 6%. The remainder has to be absorbed by pump storage, or export over night, then the peak has to be supplied via back up generation.
So they basically need at least 30% peaking capacity compared to nuclear capacity, and maybe 15% or so capacity to absorb or export excess night time generation.
By comparison, in the UK our consumption fluctuates by around 50% daily from peak to trough, so we'd either need to have a massive programme of overnight storage heaters, or maybe electric vehicle charging to get our demand curve more like the French, or we'd need to have something like 40% additional daily absorption and peaking capacity, and bare in mind that we would be unable to export it down our main interconnector to france, or any countries surrounding france because they would have no capacity to absorb the excess because they're already absorbing Frances excess (including the 2GW France currently sends to our pump storage capacity every night).
By comparison, wind, solar etc don't actually need any capacity to absorb excess generation, they can simply be switched off if there's excess, and we already possess all the peaking plants required in the form of our existing gas plants, and to some extent coal plants (which I'd like to see kept on limited hours for winter peak demand periods / long periods without wind), along with the existing pump storage and hydro capacity.
Therefore this line of argument is complete nonsense, high levels of nuclear penetration would probably require significantly more investment in the capacity to absorb the excess night time generation, on top of the peaking requirements than high levels of renewables penetration (depending on how that is implemented).
Clear enough?