thermal efficiency

American  

noun

Thermodynamics.

1. the ratio of the work output of a heat engine to the heat input expressed in the same units of energy.

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thermal efficiency British  

noun

1. the ratio of the work done by a heat engine to the energy supplied to it Compare efficiency

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Etymology

Origin of thermal efficiency

First recorded in 1905–10

Example Sentences

In addition to cutting pollution, several experiments reported improvements in brake thermal efficiency.

From Science Daily • Mar. 13, 2026

Water-based cooling systems, especially using mine pools, are ideal for managing heat load due to their thermal efficiency.

From The Wall Street Journal • Mar. 8, 2026

Its homes, which can be customized by combining various-sized modules, range from one to four bedrooms and are solar-powered, built to maximize thermal efficiency and indoor air quality.

From Los Angeles Times • May 9, 2025

F1 engines have a thermal efficiency rating of about 50%, while road-car petrol engines are generally in the region of 30%.

From BBC • Jul. 15, 2021

Table III., giving the theoretical thermal efficiency for these three symmetrical cycles of constant temperature, pressure and volume, extends from a compression ratio of � to 1⁄100th.

From Encyclopaedia Britannica, 11th Edition, Volume 11, Slice 4 "G" to "Gaskell, Elizabeth" by Various