Energy return on investment

In energy economics and ecological energetics, energy return on investment (EROI), also sometimes called energy returned on energy invested (ERoEI), is the ratio of the amount of usable energy (the exergy) delivered from a particular energy resource to the amount of exergy used to obtain that energy resource. Arithmetically, the EROI can be defined as: E R O I = Energy Delivered Energy Required to Deliver that Energy {\displaystyle EROI={\frac {\hbox{Energy Delivered}}{\hbox{Energy Required to Deliver that Energy}}}} .

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