J. P. Wild
Friedrich M. Heichelheim and P. J. Rhodes
D. W. R. Ridgway
Energy and power are closely related concepts: energy implies the capacity to do work, and power affects the rate at which work is done (energy transmitted per unit of time). The availability of energy, and the rates at which that energy can be converted into heat or mechanical work, for example, constitute fundamental limits to the performance of any economy.
“Energy” derives from the Greek ἐνέργεια. The word is used by Diodorus Siculus (