The coal plants that are heavily polluting were built in the 60s-80s. They're reaching the end of their useful life and being replaced by natural gas in the USA. China is mostly building clean coal power plants because it is the best option available to them.
Coal literally pulled China out of poverty.
Dependence on coal is not just a Chinese problem, though. Countries around the world—even European nations that tout their environmental track records—have found themselves unable to wean themselves from coal. Germany, though often celebrated for its embrace of solar and wind energy, not only gets more than half its power from coal but opened more coal-fired power plants in 2013 than in any year in the past two decades. In neighboring Poland, 86 percent of the electricity is generated from coal.
Unless humanity is ready to immediately embrace nuclear, coal is going to remain a major electric fuel.
Even my electric provider that wants to be the first in the world to go entirely green, they got 12,290 GWh from coal compared to 11,305 GWh from wind (my neck of the woods is among the windiest average in the world).
We're kind of going in circles. No governmental bodies really want to embrace nuclear. Wind is unreliable for a grid that needs constant supply. Solar is all kinds of stupid. Hydro isn't reasonably expandable nor is geothermal. Fusion isn't ready yet. Natural gas only works where it is available (especially North America but not elsewhere). So what's left the fill demand? Coal. Everyone hates coal but they would hate losing all of our nice electric things more. It's the skeleton in the closet no one talks about but is ever present.
If I didn't want to promote the use of coal power, I would have to cut my electric consumption in half. It's not possible because I rely on electric heating for the winter (can get down to -20 F/-29 C). I'd rather they burn coal 50 miles away than me burn it in my house. The only other alternatives are various forms of oil (propane or fuel oil) which are less efficient than that coal power plant and much more dangerous or chopping down trees (which there aren't many around) to burn. I'll let them keep burning that coal, spank you very much.
I'd rather destitute countries like Haiti have access to coal power rather than them deforest (
which they already did) their nation too. In the grand scheme of things, coal is win-win. The downsides are minor compared to what having no reliable electricity means.