Many old coal mines had their own electrical generators. They were self sufficient and had a good reliable supply for essential equipment like ventilation fans, water pumps, winder winch, lifting gear and coal cutters etc. In the U.K. in about 1950 colliery generating plants were shut down and the supplies were obtained from the Electricity Boards. This was a bit of a shame really, as unmarketable grades of coal could be used at the colliery generating plants' boilers.
Now Old King Coal is an enemy it appears.
G7 to agree tough measures on burning coal to tackle climate change - BBC News
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