hot-air engine

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June 29, 2026

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A hot-air engine is a type of engine that uses heated air as its working substance. The most well-known example is the Stirling engine, invented by Robert Stirling in 1816. This external-combustion engine operates by heating a gas, which expands and drives pistons. The gas is then cooled, contracts, and the cycle repeats.123

Stirling engines were historically used for pumping water and generating electricity, but their high cost limited widespread adoption. Modern research continues to explore their potential due to their efficiency, quiet operation, and ability to use various fuel sources, with current versions often using hydrogen or helium as the working fluid.23

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history of technology
Petroleum
This was the hot-air engine, for which a Scotsman, Robert Stirling, took out a patent in 1816. The hot-air engine depends for its power on the expansion and displacement of air inside a cylinder, heated by the external and continuous combustion of the fuel. Even before the exposition…
Read More
This was the hot-air engine, for which a Scotsman, Robert Stirling, took out a patent in 1816. The hot-air engine depends for its power on the expansion and displacement of air inside a cylinder, heated by the external and continuous combustion of the fuel. Even before the exposition…
Read More