[j16sdiz]

The way China building new reactor is not typical.

Most of the countries builds _one_ type of reactor, or a group of similar type of reactor. This help reduce the cost of training and certification.

China, otoh, tries to _diversify_ their reactor type.

If you look closely on how China treat techs, they have been doing the same for all tech for past 15+ years. They are strategically growing their tech profile.

[marcosdumay]

They have a huge number of people that can specialize in many different things.

But their government has actually explained it. They purposely diversify any tech that doesn't have a clear winner, so in the long term a winner appears and they can focus on it.

[dalyons]

They also, most importantly, don’t have to care if any of their reactors make economic sense. It is a single party state, and the incentive structure is very different.

[mpweiher]

Actually the way China builds nuclear reactors is very typical of the way western countries built reactors back when we still did it well: standardize, build a bunch in overlapping batches. Keep building.

That shouldn't be surprising, because they learned it from us.

We stopped doing it that way because we effectively stopped building.

China is building enough reactors that they can do this with several standardized designs. Which is smart.

The EPR has basically failed, so in the west we currently have 3 standardized generation III(+) designs: The Westinghouse AP-1000, the South Korean APR-1400 and the Japanese ABWR.

Of these, both the ABWR and the APR-1400 have been built quickly and cheaply, with the ABWR holding the record for fastest build times: under 4 years.

The AP-1000 had some very rough initial builds, because the design wasn't actually finished and it turned out what they had "finished" wasn't actually buildable. Ooops. These issues appear to have been ironed out, and a lot of countries are betting on the AP-1000: the US, Poland, China, and Ukraine. Turkey, Slovakia and Bulgaria have also expressed interest.

The EPR is essentially dead, with only the UK wanting to build two more UK-EPRs at Sitwell-C. Hopefully the EPR2 will be better, what I've seen of the specs suggests it has a good chance.

Anyway, one point I want to come back to is the "keep building".

This is actually crucial, and one of the reasons many western projects in recent years went so badly. We had forgotten how to build, no longer building a bunch in overlapping bunches, but single units decades apart.

And there comes to rub: in order to "keep building", you have to build slowly. Slow is smooth and smooth fast my guitar teacher used to say. The French built out far too quickly, constructing 55 reactors in just 15 years. Then they were done. Nothing to build until that initial batch wears out. Reactors last a long time, easily 60-80 years.

Ooops.

The key to this comes from queueing theory, Little's Law:

    L = ƛW

"the long-term average number of customers (L) in a stationary system is equal to the long-term average effective arrival rate (λ) multiplied by the average time that a customer spends in the system (W)"

https://en.wikipedia.org/wiki/Little%27s_law

So if you have a desired fleet size of 80 units and they last 80 years, you should be completing 1 unit per year. China is currently permitting 15 per year. If they keep that up throughout the construction phase, this would imply a steady-state fleet size of 1200 reactors.

That's a lot of reactors.

If you build more quickly, you won't be in steady state. Of course you can still do better than going full tilt and then stopping, smoothly modulating the build-rate.

For France, this would have meant a fleet size of 320 reactors at the rate they were going. Alternatively, the build rate for the fleet size they have would have been around one reactor every two years.

Something to keep in mind for the "not a lot of nuclear is being built"-crowd.

[Moldoteck]

most of chinese units are hualongs now