Deriving an improved dynamic EROI to provide better information for energy planners

Abstract

The two most frequently quantified metrics of net energy analysis-the energy return on (energy) investment and the energy payback period-do not capture the growth rate potential of an energy supply infrastructure. This is because the analysis underlying these metrics is essentially static-all energy inputs and outputs are treated the same, regardless of where they occur in the life cycle of the infrastructure. We develop a dynamic energy analysis framework to model the growth potential of alternative electricity supply infrastructures. An additional figure of merit, the infrastructure doubling time, is introduced. This metric highlights the critical importance of the time phasing of the initial energy investment for emplacing a given infrastructure, as opposed to the ongoing O&M energy expenditures, for the infrastructure's growth potential. The doubling time metric also captures the influence of capacity factor, licensing and construction time lags. © 2011 by the authors.