[sudosysgen]

Yes, they do to build more plants at a record pace, because they need to increase total generation at a record rate. Since renewables, which are also being built at a record pace, are not very reliable time-wise, it is needed to build reliable capacity.

Now, that capacity might be used 15-20% of the time, but it still needs to be built. For example, the UK went multiple days without ever using its fossil fuel electric plants, but they were still necessary in case of bad weather.

I agree that this is not optimal. In the best of worlds, they should use nuclear energy and hydro for base load generation. However, not everywhere in China is good for either, and their very-high-voltage long-range grid is still being built, so for many regions, which tend to be those that are poor and growing the fastest, they have opted to use fossil fuels. This isn't inconsistent with their goals.