Around Beijing, the problem is (1) use of coal as fuel with outdated poorly maintained energy producing equipment, (2) use of coal directly by peasants in the winter to keep warm (in Hebei), and (3) lots of cars with poor fuel quality (even if the emissions equipment is working, they aren't given the right quality of fuel). The solutions are quite simple: upgrade the equipment, get farmers to use natural gas for warming, and import the good black stuff from Saudi, not the cheap bad stuff (Sinopec is evil).