> And most of them are under 1GW

No, almost every one is above 1GW - divide the net capacity by the number under construction to see the power [1]. They appear to be almost all CAP1400 (1.4GW), Hualong One (1.0GW), or CAP1000 (1.0GW). I see a single Linglong 1 (100MW) under construction. Proposed are all above 1GW.

[1] https://en.wikipedia.org/wiki/Nuclear_power_in_China#Future_...