Fuel efficiency is a form of thermal efficiency, meaning the efficiency of a process that converts chemical potential energy contained in a carrier fuel into kinetic energy or work. Overall fuel efficiency may vary per device, which in turn may vary per application, and this spectrum of variance is often illustrated as a continuous energy profile. Non-transportation applications, such as industry, benefit from increased fuel efficiency, especially fossil fuel power plants or industries dealing with combustion, such as ammonia production during the Haber process.
In the context of transport, fuel economy is the energy efficiency of a particular vehicle, and is given as a ratio of distance travelled per unit of fuel consumed. Fuel economy is expressed in miles per gallon (mpg) (prevalent in the USA and UK, using their respective definitions of a gallon) or kilometres per litre (km/L) (prevalent in the Netherlands, Denmark and in several Latin American or Asian countries such as India, Japan, South Korea). The reciprocal ratio, "fuel consumption", is usually expressed in liters per 100 kilometers (L/100 km) (common in Europe, Canada, New Zealand and Australia) or litres per mil (Norway/Sweden).
Variations on a vehicle's fuel efficiency include weight-specific efficiency for freight, and passenger-specific efficiency (vehicle efficiency / number of passengers).
Read more about Fuel Efficiency: Vehicle Design, Fleet Efficiency, Energy Efficiency Terminology, Energy Content of Fuel, Fuel Efficiency of Vehicles, Fuel Efficiency in Microgravity, Driving Technique
Famous quotes containing the words fuel and/or efficiency:
“I had an old axe which nobody claimed, with which by spells in winter days, on the sunny side of the house, I played about the stumps which I had got out of my bean-field. As my driver prophesied when I was plowing, they warmed me twice,—once while I was splitting them, and again when they were on the fire, so that no fuel could give out more heat. As for the axe,... if it was dull, it was at least hung true.”
—Henry David Thoreau (1817–1862)
“I’ll take fifty percent efficiency to get one hundred percent loyalty.”
—Samuel Goldwyn (1882–1974)