Back in the 1970's at the peak of society's optimism for nuclear power, the USA was also building 10 reactors per year.
However, the population of China today is 6 times that of the USA back in the 1970's.
Therefore an argument can be made China is actually being very conservative with "only" building 10 reactors per year.
If China were to build at the rate of the USA relative to population there would be 60 reactors per year.
Is this ever going to happen? Maybe 25 years down the road......who knows?
60 reactors per year over a 10 year period gives you about 600 GW of capacity which translates to about 5000 TWh of annual electricity production. Note that Chinese electricity demand is currently 10000 TWh
But as stated previously, wind and solar are cheaper than coal or nuclear.
So it just makes more sense to focus the bulk of investment in wind and solar.
Last time I looked, China has polysilicon production capacity of 3 million tonnes, which roughly works out as 1000GW of solar panels per year. But it looks like only ~76% of that capacity is being utilised this year, so there is still scope for more solar panel production if required.
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Today, China is still growing and building fairly quickly.
But I expect the electrification of the economy to be largely complete in 10 years time.
Then electricity demand growth will be modest.