What caused the Newcomen engine's immense fuel consumption?

Answer

Repeatedly heating and cooling the entire cylinder.

The engine was extremely inefficient because the entire main cylinder had to undergo constant thermal cycling—being heated by steam and then rapidly cooled by injecting cold water—which wasted enormous amounts of thermal energy with every stroke.

What caused the Newcomen engine's immense fuel consumption?

#Videos

James Watt's Steam Engine - YouTube

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