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For comparison, gasoline engines (Otto cycle engines) typically operate at around 20-25% thermodynamic efficiency these days, and diesel efficiencies are above 40%. This is well above the 15% efficiency mentioned for steam engines around 1950, but it turns out that Otto cycle engines were also about 15% efficient at the time. I don't know what a steam design could accomplish with current technologies.
(References: Encarta: Internal-Combustion Engine and EFFICIENCY OF INTERNAL COMBUSTION ENGINES)

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by technopolitical on Wed Jul 12th, 2006 at 12:52:59 PM EST

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