"As recently as 2002, a number of Detroit Public Schools were still heated with coal. Plant in video features a Copes feedwater regulator, duplex pumps and an underfeed Detroit Stoker".
The beginning of the video shows lots of smoke but it must have been from a freshly lit boiler because I know of a number of schools, churches, etc. that used coal and never saw that much smoke.
I especially like and agree with the comment "acidorian" wrote about the video which I pasted here...."that's how all schools should be heated; they're big/old/leaky buildings that cost a lot to heat, they cost significantly less to heat with coal. additonally it's an all-american fuel sourced right here in the USA by american workers. BTW, the thick smoke at the begenning of the video was during stoker startup/shutdown. while running it produces almost no visable smoke."