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Maybe we can go back to coal-burning steam locomotives?
Steam powered this nation in much of the last half of the 19th Century until well into the 20th Century, and in the form of electrical generation, still does.
The question comes in, as what is the heat source that creates this steam from water? Wood is simply not in enough supply, and coal has already been condemned, as “too dirty” (this is not true, “clean coal” is possible). Other hydrocarbon fuels, from natural gas (methane) to refined fractions suitable for internal combustion engines or even gas turbines. Or if people really want to get exotic, a very small thorium-fueled molten salt atomic pile, which generates heat on a continuous basis, even scaled down to fit in an ocean-going vessel or a rail-bound locomotive.
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