Like everything else in China, coal production statistics are simply immense. China now consumes and produces close to 50% of all the coal in the world. Thus, changes in Chinese consumption and / or production may have a dramatic impact upon the global coal market.
If their production ever lags consumption then they will have a recession (which would affect the world economy), they buy coal on the world market (jacking up prices) or they go to nuclear power in a major way. China is installing massive amounts of renewable power, but their consumption is soaring too, and unfortunately there’s no way renewables can do it all for them.