the other way coal affected a century of transportation - it was the trade off, on top of pay, to get an engineer to design the BMW opposed cylinder motorcycle engine!

In Germany after World War I coal was scarce, forcing city dwellers to live in their kitchens as farmers did in winter. 

BMW, forbidden its former role as aircraft engine producers, accepted any production work, including building job lots of inferior motorcycle engines designed by outsiders. 

Irked by this, the company asked aircraft designer Max Friz to come up with a better engine design. Friz was a German mechanical engineer specializing in engine design, who had just made major contributions to the design of the racing engine for the 1914 Mercedes Grand Prix car (that won the French Grand Prix.) Friz also designed the first practical German aircraft engines in 1912-1913 while at Austro-Daimler. 

 Friz disliked surface vehicles, but changed his mind when offered coal to heat a bedroom which he could use as a drawing office. 

He applied rational aviation design, canceling vibration by choosing the self-balancing flat-twin as his engine architecture. He oriented it with its finned cylinders projecting right and left into undisturbed cooling air—not in the “wind shadow” of the front wheel. His basic design has now endured for over a century.

https://www.cycleworld.com/blogs/ask-kevin/kevin-cameron-top-picks-from-mecum-las-vegas-auction/