France doesn't have any new reactors under construction. Its annual nuclear generation peaked in 2005:
~/git/iaea-pris % sqlite3 pris_data.db
sqlite> select year, sum(electricity_supplied_gwh) from reactor_statistics, reactor_operating_history where reactor_statistics.reactor_id=reactor_operating_history.reactor_id and country_code='FR' and year > '1999' group by year;
year sum(electricity_supplied_gwh)
---- -----------------------------
2000 395392.3
2001 401256.49
2002 415110.33
2003 421028.62
2004 428040.69
2005 431179.56
2006 429819.63
2007 420129.49
2008 419800.32
2009 391752.97
2010 410086.42
2011 423509.48
2012 407437.88
2013 405898.51
2014 418001.4
2015 419035.02
2016 386452.88
2017 381846.02
2018 395908.34
2019 382402.75
2020 338735.78
2021 363394.15
2022 282093.23
2023 323773.23
2024 364390.78
France is planning new EPR2 reactors, but no construction is expected to start before 2027 and none would run before the 2030s. I put little trust in announcements of future plans without actual construction work, whether the plans are for nuclear reactors, wind farms, data centers, or any other major investment.
Look at the number of planned reactors and the number of reactors likely reaching EOL. France plans to build fewer than fifteen new plants (delivery date tbd). If they started building all of them today half of their fleet would be fifty years old by the time construction was done.
Once again: source? Mycle Schneider by any chance?
Anyway: those numbers are not "reactors likely reaching EOL". Those are reactors reaching the end of their original operating license.
These two things are not the same. At all.
Initial operating licenses were intentionally relatively short, because at the time there was no experience with the longevity of reactors. So you conservatively license towards the short end.
Now that we have that experience, reactor operating licenses are getting extended. A lot. The first reactors in the US have had their licenses extended to 80 years, and the current consensus appears to be that 100 won't be a problem.
So France won't be running low on nuclear power anytime soon. Unless you're Mycle Schneider and/or confuse "current operating license expiry" with "EOL".
France does not have any new reactors currently under construction because until March 2023, expansion of nuclear generating capacity was forbidden by law.
So even to build the one Flamanville 3 reactor, they had to shut down two older reactors in Fessenheim in order to not have an illegal increase in capacity.
Now that the law has been rescinded, they are planning 6 simplified EPR2 reactors, taking lessons from the fairly catastrophic EPR project FV3.
(Of course, even that catastrophic reactor will be more profitable than any intermittent renewable projects in, for example, Germany, but hey, the standards for what counts as "success" and what as "failure" are different for nuclear and for renewables).
France also currently does not need to urgently expand their nuclear fleet, so the schedule for the EPR2s matches those needs and the need to fully account for the problems with FV3. Instead, they are increasing the production of their existing fleet, both by operational upgrades and also by increasing use of intermittent renewables to cover variations in demand, allowing the nuclear fleet to run closer to fully rated capacity instead of having to load-follow.
