Comments by "Henry Law" (@henrybn14ar) on "Steam Boilers in the 1900's - The Unusual Case of the Car and Ship" video.

@mahbriggs Steam initially went out of use for trains in the drier regions of the US due shortage of water. Then the manufacturing capacity for diesel electric made it competitive. Steam in Europe was phased out primarily due to the maintenance costs associated with the use of coal. Thermal efficiency had and has little to do with the choice. Steam locomotives built for tourist routes in the 1990s run on light oil. In practice they use about the same amount of fuel for the same amount of work. Steam locomotives have smaller transmission losses due to direct drive, and waste heat can be utilised for train heating and auxiliary services. In theory internal combustion wins hands down. In practice the advantages are tighter. Steam has not been able to make a comeback due to inertia and lack of infrastructure. Given a decent sized production run the lower unit cost would make it competitive for lightly trafficked routes.
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