A measure of how effectively fuel is transformed into usable energy. Each type of fuel is deemed to have a specific energy-producing potential per unit of weight, but some or most of that potential is lost during production or refining.
While 100% efficiency is always the goal, in practice the fuel conversion efficiency of a typical commercial steam turbine generator is only about 30 percent efficient. Household natural gas furnaces typically achieve only about 70% efficiency. Automobiles rarely boast better than 20% fuel conversion efficiency, and even a well-tuned bicycle rates about 75%.
See also:turbine, combustion turbine, energy efficiency, fuel conversion efficiency