In a recent Point of View piece, William Pickard made an excellent case for the importance of energy return on investment (EROI) as a useful metric for assessing longterm viability of energy-dependent systems from bands of hunter-gatherers, to modern society and, finally to the specific case of a solar electricity generating project. The author then highlighted a seeming disparity between a number of different research groups 1) Fthenakis group at Brookhaven, 2) Prieto group in Madrid, 3) Weißbach group in Berlin, and 4) Brandt group at Stanford all of whom have recently published values for the EROI (or similar metric) for solar photovoltaic (PV) technologies. Unfortunately, in so doing, the author directly compares results calculated using different system boundaries, methodologies, and assumptions. It is the purpose of this response to (1) adjust the results for the four groups to better compare like systems and (2) outline details of two methodological issues common in the EROI literature. The objective of these two activities is to explain much of the apparent disparity between the different EROI values produced by the different research groups.
Carbajales-Dale, MRaugei, Marco Fthenakis, VBarnhart, C
Faculty of Technology, Design and Environment\Department of Mechanical Engineering and Mathematical Sciences
Year of publication: 2015Date of RADAR deposit: 2016-02-17