Energy efficiency may refer to:
- Efficient energy use, sometimes simply called energy efficiency.
- Energy efficiency in transportation.
- Energy conversion efficiency, the ratio between the output and input of an energy conversion machine.
- Energy conservation, efforts made to reduce energy consumption.
Famous quotes containing the words energy and/or efficiency:
“The flattering, if arbitrary, label, First Lady of the Theatre, takes its toll. The demands are great, not only in energy but eventually in dramatic focus. It is difficult, if not impossible, for a star to occupy an inch of space without bursting seams, cramping everyone else’s style and unbalancing a play. No matter how self-effacing a famous player may be, he makes an entrance as a casual neighbor and the audience interest shifts to the house next door.”
—Helen Hayes (1900–1993)
“Nothing comes to pass in nature, which can be set down to a flaw therein; for nature is always the same and everywhere one and the same in her efficiency and power of action; that is, nature’s laws and ordinances whereby all things come to pass and change from one form to another, are everywhere and always; so that there should be one and the same method of understanding the nature of all things whatsoever, namely, through nature’s universal laws and rules.”
—Baruch (Benedict)