Capacity factor is % utility of your max generating power output.% utility is lower if you can't produce or no one is willing to buy so you don't produce max.
If you produce min deman load with nuclear at 90% capacity. The it's all good.Once you are above that demand slack means production capacity is wastes. Currently nuclear is the last to stop producing as it's variable costs are so low. If nuclear is a larger part of your grid it will tend to have a capacity factor that is equal to the average demand.
Is France one, and does anyone know what their's is?
Sure these are supposed by GenIII, but are currently not competitive in any way with other power sources in economic terms. 10.5 billion buys you about the same in offshore wind e.g. 3 london array installations ( 2 billion per 600 MW * 50% capacity, compared to 10.5 billion per 1600mw * 90% capacity) = 10/(1.6*.9). Big difference is london arrays take 1 year to build instead of 10 for nuclear. That alone gives a mayor difference in real project costs.
The, unfortunate, reality is nuclear reactors are not build in serial production. Therefore learning costs do not decrease as much as you might expect. Main reasons are distance between sites, meaning many construction workers do not work on all sites. You see at most 10 units for one design. Time between forgings for mayor means parts are not made in large series so relatively little is learned. All 4 EPR sites seem to have suffered from the same issues with concrete pouring so even there learning might not have happened.
Economically nuclear is in a real bind: for regulatory reasons you want big plants (1gw+), but for economic reasons you want many small ones (about 100mw). The current 1.6GW units are in many ways to big and smaller reactors would be much better project/knowledge wise. Yet the regulatory overhead for each new unit means that the firms went towards designing larger units.
Bechtel marine nuclear powerplants could actually be produced in series as they are small enough to be build off site and could be made economically viable. Yet I don't expect that Bechtel ever will.
But lest assume Arreva learns how to build EPRs for 5 billion and in 5 years. Which gives you
EPR done right 5 billion / (1.6 GW * .7 historic capacity factor) = 4.4 to 5 billion / (1.6 GW * .9 best capacity factor) = 3.2 London array 2 billion / (.63 GW * .50 historic capacity factor) = 6/2
Even in this very optimistic scenario, offshore wind is between 100% and 60% more expensive on construction costs. Offshore wind however, still has lower opex and a much better learning curve. i.e. if ordering a london array today costs will be less than 2 billion. (big difference in reporting is that wind projects include interconnect costs which current nuclear projects do not due to sitting next to existing plants).
Wind farms, also have positive decommissioning costs (those steel towers have real economic value at end of life).
Both types of projects have issues with nimbys.
4.5 billion capex is a really good number for nuclear in a competent regulatory environment. Still its double the estimated project cost when started.
Funnily enough nuclear and renewables really compete hard because of this. Extra power production is nearly nothing for both compared to opex and capex, so if you can produce you shall until returns hit 0. Both love energy storage for that reason. Nuclear is more dependable i.e. less peakers on because of supply issues. But capex for wind and solar are trending too be lower, as is time to market. Leading to less risks, which affects project planning a lot.
CSPs with inbuilt storage tend to go to lower generator capacity factors so that they can take a share of the peak shaving market, due to their relative good dispatch ability (send power to the market when wanted, instead of when you can).
Wind and solar projects tend to be online and producing quickly in time measured from first concrete poured to power send to market, certainly relative to nuclear in practice. Projects also tend to be smaller scale and in independent phases. Nuclear is added a GW at a time to the market, solar and wind in smaller 50-100mw projects. i.e. wind&solar are project wise much more agile.