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Updated: Jun 16, 2026

Determining the Contribution of the Energy Systems During Exercise
Published on: March 20, 2012
Year in review--EROI or energy return on (energy) invested
David J Murphy1, Charles A S Hall
1Department of Environmental and Forest Biology, and Program in Environmental Science, State University of New York, College of Environmental Science and Forestry, Syracuse, New York, USA. djmurp03@syr.edu
Abstract:
There have been five foremost empirical efforts regarding energy return on investment (EROI) analysis over the past few years, including the topics of: (1) whether corn ethanol is a net energy yielder; (2) a summary of the state of EROI for most major fuel types; (3) alternative applications of EROI, such as energy return on water invested (EROWI); (4) the relation between EROI and the economy; and (5) an attempt to calculate the minimum EROI for a sustainable society. This paper offers a review of these five main areas of interest and provides a history of the development of EROI as well as a review of some of the various definitions of EROI and how they apply to EROI analyses. The paper concludes by listing numerous areas of improvement that are needed within EROI research.
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