They currently get 2-3% of their electricity from nuclear:

https://www.technologyreview.com/s/539691/china-will-soon-le...

A 5x increase in 15-20 years gets you to 10-15%. While that's good, I don't think it's enough given the current rate of CO2 production. It's hard to complain because they're doing a lot more than everyone else. Unfortunately, we need to find a way to do more.