They're cost effective when the sun is shining or wind is blowing but are strongly tied to increased high carbon fracked natural gas otherwise. When batteries are used the Energy Return on Investment drops below what's necessary to sustain industrialized civilization (around 5:1).
Even without including cost overruns and decomissioning, wind energy costs the same per kilowatt of capacity[0,1].
And the actually produced energy as share of capacity (= the capacity factor) is way better than most think. For the nuclear plants in France it currently is just over 70%, while it is about 50% globally for offshore wind parks [2,3]
Also there is currently no offshore wind park, as only offshore would approach the 50% capacity factor, but they won't, they will be in the 43% as estimated by renewables.ninja
The price of the MWh of offsore park will be from 44 to 150€/MWh, where EDF is forced to sell its nuclear at 42€/MWh, average price of wind in 2020 93€/MWh.
I disagree that current onshore wind in France is not 50%, only 21%; also maybe you were comparing the low capacity factor of French nuclear because it is used for load following and curtailed in summer because it is scaled for winter usage using restive heating. And comparing it to offshore with intermitttent power, not dispatchable in the best location. Totally misleading.
Comparing worst capacity factor (for cited reasons) with best CF without saying it is offshore in some of the best location is misleading. Also is comparing dispatchable and intermittent/fatal. There a other factors to consider like reserve ratio, or how the production can cover the power needs over the year, it gives hints at how you need to scale seasonal storage.
It sounds like you confirmed their nuclear capacity factor ("just over 70%") and pointed out that French wind farms have a lower capacity factor (21.1%) than wind farms on average. I don't think that constitutes evidence that they are "completely wrong on [their] numbers".
Nuclear: " Companies that are planning new nuclear units are currently indicating that the total costs (including escalation and financing costs) will be in
the range of $5,500/kW to $8,100/kW or between $6 billion and $9 billion for each 1,100
MW plant." https://www.synapse-energy.com/sites/default/files/SynapsePa...
Then it's now my turn to call your numbers misleading ;) I don't think you can directly compare the two that way because a) The French government heavily invested in nuclear for strategic reasons, not directly economical ones. The EDF still is essentially state-run. We can't really infer cost arguments from this. b) Practically all nuclear plants in France are decades old, and had many years for recouping initial investments. Current market prices for energy are therefore not a good argument for costs of newly built plants.
If we look at the costs of constructing new nuclear plants (which the article we comment on is about), France is a particularly bad example, with current costs already at $11B for 1600MW of capacity for the Flamanville project. https://www.reuters.com/article/us-edf-nuclear-flamanville/e...
That was not obvious, it was written like a French nuclear with French wind comparison.
And also that is misleading because comparing the low capacity factor of French nuclear because it is used for load following and curtailed in summer because it is scaled for winter usage using restive heating. And comparing it to offshore with intermittent power, not dispatchable in the best location, does not make sense. With penetration wind will also be curtailed, and is already happening in china and Germany.
https://doi.org/10.1016/j.esr.2019.100399