Comment by godelski

Of those being built, most of them began construction in the last 2 years[0]. If you look at the timelines, China is doing much better than others on timelines. For the economies of scale, one needs to only look at the historical example of France (same link).

This issue here is that when you infrequently build reactors you have to reinvent all the tooling to build the sub-components. This is actually what caused the Westinghouse bankruptcy. But your question is about 7 years being a long time. China seems to be pushing that down to 5, but how much time are you expecting? There's always a trade-off here and frankly big projects take time.

I suspect you have an incorrect mental model where you think other energy systems are constructed much faster. I pulled a random US example from the list of photovoltaic systems[1] and so let's look at Westlands Solar Park which is a 2GW facility[2]. We can see planning began before 2014 (since that's when a real estate company was involved), initial demonstrations in 2014 (2MW), construction began in 2020, took another 1-2 years to get 250MW online, another year (2023) to get another 420MW online, and the facility isn't expected to be finished until 2025. So we can say that the time takes is at least 5 years. For reference let's look at Yangjiang, China is doing about 6 on their reactors which are around the 1GW scale. And you'll notice that while staggered, these are often parallel so the whole facility is going online in roughly 10 years, but that's 6GW where past the initial first 8 years, one is going online every year. This example was even slowed down by Fukushima. But you can see they've done that a few times and can tell that that was their foray into building nuclear power, and after success you do more. As long as they have good construction (and we should expect these to be higher quality than many other things in China because there are international inspectors and overseers), then I expect them to even get a bit faster. But the overall timeframe for building isn't significantly worse than building a solar plant of a much smaller capacity.

[0] https://en.wikipedia.org/wiki/List_of_commercial_nuclear_rea...

[1] https://en.wikipedia.org/wiki/List_of_photovoltaic_power_sta...

[2] https://en.wikipedia.org/wiki/Westlands_Solar_Park#Phases