Efficiency
Efficiency could mean:
- Energy efficiency, useful work per quantity of energy
- Energy conversion efficiency, desired energy output per energy input
- Energy conservation, reducing the use of energy
- Electrical efficiency, useful power output per electrical power consumed
- Fuel efficiency, converting energy in fuel to kinetic energy or work
- Specific impulse, in propulsion systems, a measure of fuel-efficiency
- Volumetric efficiency, in internal combustion engine design
- Lighting efficiency, visible light from a light source per unit of power, in lumens per watt
- Mechanical efficiency, the effectiveness of a simple machine, mechanical advantage over ideal mechanical advantage
- Thermodynamic efficiency, useful work per change in heat
- Exergy efficiency, measure of 2nd-law themodynamic loss
- Thermal efficiency, useful work per the higher heating value of the fuel
- Radiation efficiency, ratio of radiated power to power absorbed at the terminals of an antenna
- Efficiency (aerodynamics), for fixed wing aircraft the Lift-to-drag ratio
- Efficiency (economics), a general term, to capture the amount of waste or other undesirable features
- Pareto efficiency, making one individual better off, without making any other individual worse off
- Kaldor-Hicks efficiency, like a less stringent Pareto efficiency
- Allocative efficiency, an optimal distribution of goods
- The optimisation of a social welfare function
- Efficiency wages, paying workers more than the market rate for increased productivity
- Efficiency (statistics), a measure of desirability of an estimator
- Efficiency ratio, expenses as a percentage of revenue, etc.
- Efficiency Movement, of the Progressive Era 1890-1932, advocated efficiency in the economy, society and government
- Material efficiency, compares material requirements between construction projects or physical processes
- Textual efficiency, density of a message
- Algorithmic efficiency, the speed and space requirements of a computer program
- Quantum efficiency, a measure of sensitivity of a photosensitive device: the percentage of photons hitting the photoreactive surface that will produce an electron–hole pair