Intergenerational equity and dual discounting

Abstract

AbstractDual discounting is a new approach under consideration for use in environmental cost–benefit analysis. This paper updates the literature on this subject and subjects it to the assessment of an international panel of experts on environmental discounting by means of a Delphi study. Subsequently, a case study provides some findings deriving from the practical application of this strategy as the choice of discounting scenario in the economic evaluation of a plant for the desalination of irrigation return water, aimed at halting the degradation of a wetland. There are theoretical and practical reasons to support the use of this discounting approach in relation to projects with intergenerational impact, where the environmental effects are considerable in relation to market effects. Although still under investigation, the dual discounting approach appears to provide an appropriate methodological platform enabling the quantification of the degree of intergenerational equity implicit in the project.