There are safety-related limits (power modulation proportion, duration of a pause needed after each modulation, modulations frequency...) to nuclear load-following capacity, and the very combustible status is a major parameter.
Quote:
« un réacteur peut varier de 100 % à 20 % de puissance en une demi-heure, et remonter aussi vite après un palier d’au moins deux heures, et ce deux fois par jour »
Proposed translation: "a reactor power output can vary from 100% to 20% in 30 minutes, then after 2 hours can go back to 100% at the same speed, and can cycle this way 2 times per day".
This is quite a good performance when it comes to load-following (French engineers are very good at this), however it is insufficient in the real world (save any ridiculously expensive over-provision of nuclear reactor, most idling) and very weak compared to gas turbines performances.
Even in nuclear-packed France (which exports electricity) fossil fuels are also burnt in order to produce electricity since nuclear's inception, for most of the load-following and peak (about 9% in 2021), and it would be much worse without hydro.
https://ourworldindata.org/grapher/share-elec-by-source?coun...
On the other hand green hydrogen (produced by intermittent renewables at over-electric-generation time) can be stored then used at insufficient-generation time.
There are safety-related limits (power modulation proportion, duration of a pause needed after each modulation, modulations frequency...) to nuclear load-following capacity, and the very combustible status is a major parameter.
Pertinent document (French ahead!): https://www.sfen.org/rgn/expertise-nucleaire-francaise-suivi...
Quote: « un réacteur peut varier de 100 % à 20 % de puissance en une demi-heure, et remonter aussi vite après un palier d’au moins deux heures, et ce deux fois par jour »
Proposed translation: "a reactor power output can vary from 100% to 20% in 30 minutes, then after 2 hours can go back to 100% at the same speed, and can cycle this way 2 times per day".
This is quite a good performance when it comes to load-following (French engineers are very good at this), however it is insufficient in the real world (save any ridiculously expensive over-provision of nuclear reactor, most idling) and very weak compared to gas turbines performances.
Even in nuclear-packed France (which exports electricity) fossil fuels are also burnt in order to produce electricity since nuclear's inception, for most of the load-following and peak (about 9% in 2021), and it would be much worse without hydro. https://ourworldindata.org/grapher/share-elec-by-source?coun...
On the other hand green hydrogen (produced by intermittent renewables at over-electric-generation time) can be stored then used at insufficient-generation time.