The effectiveness with which energy is created, managed and/or consumed.

In the energy industry, a distinction is drawn between energy efficiency and demand-side management programs. DSM programs are usually sponsored and financed by utilities and energy distribution companies, while efficiency programs don't typically have a particular sponsor or financial supporter.

Energy efficiency is often used interchangeably with energy conservation, but depending on the context the two terms may have different intended meanings. Efficiency can refer specifically to the effective use of available energy, and conservation can refer to reduction of energy use regardless of its availability.

See also: