Lets add Flamanville 3 to the "experience" graph in the article. The only reason it gets pushed through is for France to have an industrial base enabling nuclear submarines, carriers and weapons.
> Lets add Flamanville 3 to the "experience" graph in the article. The only reason it gets pushed through is for France to have an industrial base enabling nuclear submarines, carriers and weapons.
That's garbage.
- The reason Flamanville 3 takes so much time is precisely because it is a prototype on a new design that never have been produces in series, nor even tested. That supports 100% what is said here: If you want to reduce cost, mass produce.
- Submarines and carrier nuclear reactors are completely different beast that have nothing to do with either Flammanville 3 or the existing nuclear park.
> Submarines and carrier nuclear reactors are completely different beast that have nothing to do with either Flammanville 3 or the existing nuclear park.
To be completely fair, the french nuclear industry is a small world. DCNS (now called Naval Group) did design and manufacture thermal exchanger for civilian nuclear reactors. On the other hand, if I remember correctly, they do work with Areva (now Orano) for some part of the nuclear submarine.
Company that can produce parts (even things like tubing or screws) for nuclear reactors are very few, so they often end up working for civilian and military application.
All of this to say that the civilian and military nuclear industry are very much intertwined, feed each other and in many ways, keep each other alive.
From the link it looks like it had many changes implemented to improve safety:
The EPR is a so-called “evolutionary” reactor, that is to say that its design is based on that of existing reactors, the French N4 type nuclear reactors and the German Konvoi . It thus benefits from proven technologies and operating feedback from its predecessors.
It is a powerful reactor with a production capacity of 1,600 megawatts (MWe) compared to 1,450 MWe for the latest reactors built in France (type N4). It is designed for a service life of 60 years .
Significant changes have however been introduced compared to existing reactors
Perhaps more importantly, there's a pretty long engineering history of assuming that "similar" means "don't need to test as much" not working out. Any time you make a change, you can and should be testing the parts as though they were a new design. I mean the most recent example of that was the Boeing MCAS.
I wouldn't call Ariane 5 an evolution of Ariane IV.
Code and digital system re-use in aerospace systems is not uncommon. After all, the fly-by-wire computer system on board the Space Shuttle was derived from the original Apollo flight computer, and they are two very different space vehicles..
Right but the point is it doesn't let you make assumptions that tests aren't needed, just that you expect them to be likely to pass. The design still has to be tested as though its a new system, it's just the re-use hopefully saved some development time and the testing hopefully finds fewer issues.
A new system requiring extensive testing would have alerted the FAA that something was off, and possibly led to a more costly re-certification they were trying to avoid.
That aircraft should never have been allowed to fly.
It doesn't matter if it's an evolution or a revolution - a change of any sort means new tooling to produce the components, new procedures to assemble them, new analysis to certify that they will all work together, and new training for everyone involved to do all the above.
All this was known before starting the building process, and the builder planned to deliver the reactor in 2012. It is late (right now: not delivered) mainly because project management and quality insurance were abysmal:
https://en.wikipedia.org/wiki/Flamanville_Nuclear_Power_Plan...
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.
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.
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.
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.
> 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.
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.
> 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].
The N4 double containment is a mainly quantitative change, as are all the other changes you mentioned: the very architecture remains the same, as do the associated exploitation processes.
Those modifications were big enough to justify seeing the N4 as a "new design" because the French worked hard to master this design, and since 1981 (Nuclear Technical Cooperation Agreement, NTCA) Westinghouse & the French formally exchanged know-how. Moreover Westinghouse didn't work on the N4 and it escaped the Westinghouse license (which expired in 1992). However the very design isn't disruptive.
As for this approach efficiency the note #17 seems pertinent.
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.
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.
https://imgur.com/6G2RBa0
https://en.wikipedia.org/wiki/Flamanville_Nuclear_Power_Plan...