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The costs of the French nuclear scale-up: A case of negative learning by doing https://www.sciencedirect.com/science/article/abs/pii/S0301421510003526 https://w

The costs of the French nuclear scale-up: A case of negative learning by doing https://www.sciencedirect.com/science/article/abs/pii/S0301421510003526 https://www.sciencedirect.com/science/article/abs/pii/S03014...

pyrale 3y ago
That article neglects that the plants built by the end of the program were not the same as the plants built in the beginning. Within each "pallier", a speedup can clearly be observed. Likewise, costs can hardly be compared if you don't look at the same models. [1]: https://fr.wikipedia.org/wiki/Centrale_nucl%C3%A9aire_en_France#/media/Fichier:Chrono-parc-nucleaire-francais.svg https://fr.wikipedia.org/wiki/Centrale_nucl%C3%A9aire_en_Fra...
- natmaka 3y ago
  I have no idea how a speedup appears to you. On the graph it is quite clear that, with time (and therefore experience), the average amount of time needed to build one is raising.
  - pyrale 3y ago
    Not sure how you read that in the graph. What I read: model : first reactor -> last reactor CP0 : 65 months -> 60 months CP1 : 73 months -> 64 months CP2: 56 months -> 79 months P4: 82 months -> 74 months P'4: 85 months -> 89 months N4: 151 months -> 104 months That's 2-3rds of the builds showing a speedup. The results are even more striking if you calculate the correlation between start date and build time for any 2 reactors of the same model.
    - natmaka 3y ago
      Sorry, I didn't expose it clearly. Yes, I considered the long-term experience gain (columns, not lines: from 65 to 151 and from 60 to 104). The first nuclear plants were theoretically the most difficult to build as the local industry was less adjusted to building such things, especially specific components. As those reactor 'models' were very similar (there is no quantum leap) pertinent experience (processes, tooling...) accumulated. However there was no reduction of 'intensity' (investments, amount of simultaneous building projects, foreseeable projects...) as all this was encompassed by a huge national programme (the 'Plan Messmer'). Therefore it seems that both min and max time to completion should diminish with time.
      - pyrale 3y ago
        > Yes, I considered the long-term experience gain (columns, not lines: from 65 to 151 and from 60 to 104). [...] As those reactor 'models' were very similar [...] They're not the same buildings. A N4 is much larger than a CP0, uses different technologies, has more safety features, produces much more power, etc. To compare with another tech topic, that's like expecting SpaceX to design or build their spaceship faster or cheaper than they designed their falcon. That's unlikely, even though falcon knowledge definitely benefited the design of their new craft.
        natmaka 3y ago
        > They're not the same buildings Not exactly the same but same generation, architecture and design (Westinghouse), slightly (not fundamentally) enhanced. Stating that new features add such a large amount of work (relatively to the total amount) that it compensates for the knowledge gained thanks to previous projects is debatable. Between the oldest (CP0) and newest (N4) aren't the key differences limited to a same machine and command room shared (CP0) or not (N4) between reactors, scale (CP0's nominal power being lower), and details related to fuel rods and pipes? In which way are they dissimilar to the point of absorbing the effect of gained knowledge and adding such delays? Even the shiny new EPR is a mere enhancement of the core design dating back ~1970. Sorry, I don't know enough about SpaceX to have an opinion.
        pyrale 3y ago
        > Even the shiny new EPR is a mere enhancement of the core design dating back ~1970. If you push this logic to its end, even a tesla car is a mere enhancement of the electric cars produced in 1900. There is no breaking change like wings, the ability to teleport or supersonic speed. If you look in details what changed between CP0's and N4's though, there's quite some change [1]: N4's have a double containment enclosure while CPO's have a single one, the vessel contains 400m3 vs. 270m3 and weights almost 50% more, sustains 15 mor bars and 15 more °Cs, and it produces almost 60% more power. Enough progress for Westinghouse to value Framatome's experience to the point that they became a partner, stopped paying license fees and earned the right to export their design[2]. [1]: https://fr.wikipedia.org/wiki/Centrale_nucl%C3%A9aire_en_France#Comparatif_entre_r%C3%A9acteurs https://fr.wikipedia.org/wiki/Centrale_nucl%C3%A9aire_en_Fra... [2]: https://www.lemonde.fr/archives/article/1981/01/24/framatome-met-fin-a-l-accord-de-licence-qui-le-liait-au-groupe-americain-westinghouse_2717957_1819218.html https://www.lemonde.fr/archives/article/1981/01/24/framatome...
anovikov 3y ago
Negative learning by doing is very easy to explain: as you go, you realise many perils and dangers of this thing that you were not aware of in the beginning, and those result in a lot of safety precautions added in subsequent projects, increasing the costs.
- thriftwy 3y ago
  I can't imagine how TCO will not be much lower for subsequent ones, though.
  - Retric 3y ago
    Redundancy generally costs more to maintain not less. Aka design 1 has 500 pumps, design 2 has 600 and is safer but now there’s more equipment to main and more complex plumbing etc.
    - thriftwy 3y ago
      I begin to understand the logic behind the US derailings. The idea here is that maintenance is much, much cheaper than rescue operations. If 100 more pumps let you run for years without a scram, go along and order them.
      - Retric 3y ago
        That assumes it’s actually a benefit. The point here is the “100 pumps” raise costs and complexity for zero benefit.

pyrale 3y ago

That article neglects that the plants built by the end of the program were not the same as the plants built in the beginning. Within each "pallier", a speedup can clearly be observed. Likewise, costs can hardly be compared if you don't look at the same models. [1]: https://fr.wikipedia.org/wiki/Centrale_nucl%C3%A9aire_en_France#/media/Fichier:Chrono-parc-nucleaire-francais.svg https://fr.wikipedia.org/wiki/Centrale_nucl%C3%A9aire_en_Fra...

natmaka 3y ago
I have no idea how a speedup appears to you. On the graph it is quite clear that, with time (and therefore experience), the average amount of time needed to build one is raising.
- pyrale 3y ago
  Not sure how you read that in the graph. What I read: model : first reactor -> last reactor CP0 : 65 months -> 60 months CP1 : 73 months -> 64 months CP2: 56 months -> 79 months P4: 82 months -> 74 months P'4: 85 months -> 89 months N4: 151 months -> 104 months That's 2-3rds of the builds showing a speedup. The results are even more striking if you calculate the correlation between start date and build time for any 2 reactors of the same model.
  - natmaka 3y ago
    Sorry, I didn't expose it clearly. Yes, I considered the long-term experience gain (columns, not lines: from 65 to 151 and from 60 to 104). The first nuclear plants were theoretically the most difficult to build as the local industry was less adjusted to building such things, especially specific components. As those reactor 'models' were very similar (there is no quantum leap) pertinent experience (processes, tooling...) accumulated. However there was no reduction of 'intensity' (investments, amount of simultaneous building projects, foreseeable projects...) as all this was encompassed by a huge national programme (the 'Plan Messmer'). Therefore it seems that both min and max time to completion should diminish with time.
    - pyrale 3y ago
      > Yes, I considered the long-term experience gain (columns, not lines: from 65 to 151 and from 60 to 104). [...] As those reactor 'models' were very similar [...] They're not the same buildings. A N4 is much larger than a CP0, uses different technologies, has more safety features, produces much more power, etc. To compare with another tech topic, that's like expecting SpaceX to design or build their spaceship faster or cheaper than they designed their falcon. That's unlikely, even though falcon knowledge definitely benefited the design of their new craft.
      - natmaka 3y ago
        > They're not the same buildings Not exactly the same but same generation, architecture and design (Westinghouse), slightly (not fundamentally) enhanced. Stating that new features add such a large amount of work (relatively to the total amount) that it compensates for the knowledge gained thanks to previous projects is debatable. Between the oldest (CP0) and newest (N4) aren't the key differences limited to a same machine and command room shared (CP0) or not (N4) between reactors, scale (CP0's nominal power being lower), and details related to fuel rods and pipes? In which way are they dissimilar to the point of absorbing the effect of gained knowledge and adding such delays? Even the shiny new EPR is a mere enhancement of the core design dating back ~1970. Sorry, I don't know enough about SpaceX to have an opinion.
        pyrale 3y ago
        > Even the shiny new EPR is a mere enhancement of the core design dating back ~1970. If you push this logic to its end, even a tesla car is a mere enhancement of the electric cars produced in 1900. There is no breaking change like wings, the ability to teleport or supersonic speed. If you look in details what changed between CP0's and N4's though, there's quite some change [1]: N4's have a double containment enclosure while CPO's have a single one, the vessel contains 400m3 vs. 270m3 and weights almost 50% more, sustains 15 mor bars and 15 more °Cs, and it produces almost 60% more power. Enough progress for Westinghouse to value Framatome's experience to the point that they became a partner, stopped paying license fees and earned the right to export their design[2]. [1]: https://fr.wikipedia.org/wiki/Centrale_nucl%C3%A9aire_en_France#Comparatif_entre_r%C3%A9acteurs https://fr.wikipedia.org/wiki/Centrale_nucl%C3%A9aire_en_Fra... [2]: https://www.lemonde.fr/archives/article/1981/01/24/framatome-met-fin-a-l-accord-de-licence-qui-le-liait-au-groupe-americain-westinghouse_2717957_1819218.html https://www.lemonde.fr/archives/article/1981/01/24/framatome...

anovikov 3y ago

Negative learning by doing is very easy to explain: as you go, you realise many perils and dangers of this thing that you were not aware of in the beginning, and those result in a lot of safety precautions added in subsequent projects, increasing the costs.

thriftwy 3y ago
I can't imagine how TCO will not be much lower for subsequent ones, though.
- Retric 3y ago
  Redundancy generally costs more to maintain not less. Aka design 1 has 500 pumps, design 2 has 600 and is safer but now there’s more equipment to main and more complex plumbing etc.
  - thriftwy 3y ago
    I begin to understand the logic behind the US derailings. The idea here is that maintenance is much, much cheaper than rescue operations. If 100 more pumps let you run for years without a scram, go along and order them.
    - Retric 3y ago
      That assumes it’s actually a benefit. The point here is the “100 pumps” raise costs and complexity for zero benefit.