Steam car

A steam car is a car (automobile) powered by a steam engine. A steam engine is an external combustion engine (ECE) where the fuel is combusted away from the engine, as opposed to an internal combustion engine (ICE) where the fuel is combusted within the engine. ECE have a lower thermal efficiency, but it is easier to regulate carbon monoxide production.

The first experimental steam powered vehicles were built in the 17th and 18th century, but it was not until after Richard Trevithick had developed the use of high-pressure steam, around 1800, that mobile steam engines became a practical proposition. By the 1850s it was viable to produce them on a commercial basis: steam road vehicles were used for many applications.

Development was hampered by adverse legislation from the 1830s and then the rapid development of internal combustion engine technology in the 1900s, leading to their commercial demise. Relatively few steam powered vehicles remained in use after the Second World War. Many of these vehicles were acquired by enthusiasts for preservation.

The search for renewable energy sources, has led to an occasional resurgence of interest in using steam power for road vehicles.

A steam engine is an external combustion engine (ECE: the fuel is combusted away from the engine), as opposed to an internal combustion engine (ICE: the fuel is combusted within the engine). While gasoline-powered ICE cars have an operational thermal efficiency of 15% to 30%, early automotive steam units were capable of only about half this efficiency. A significant benefit of the ECE is that the fuel burner can be configured for very low emissions of carbon monoxide, nitrogen oxides and unburned carbon in the exhaust, thus avoiding pollution.

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Wikipedia