Retirement of steam locomotives by country

Beginning in 1917, steam locomotives, which consume large amounts of fuel and even more water, were gradually retired and replaced by diesel from the 1920s. Railway electrification started in the 1880s onwards, which required much more infrastructure before electric locomotives could come in use. The timeframe of these processes varied by country. Leading electrification was Switzerland, having 50% of the grid electrified by 1928, with long Trans-Alpine tunnels, steep inclines, small radius turns, and the availability of hydro electric power but lack of domestic coal mines.

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