• Journal of Environmental Policy
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• v.12 no.4
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• pp.71-92
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• 2013

Unlike general public investment projects, when it comes to environmental public investment projects, there is a gap between those who pay the costs, and those who receive the benefits. This is because of the long term nature of environmental investments, which entails that the majority of the costs are paid by the current generation, while the benefits are reaped by future generations. Because of this, when the social discount rate is set at a standard, singular rate, an issue of relative underestimation of the benefits reaped by future generations may occur during the analytic process. This paper begins with the recognition of this problem, and attempts to estimate a suitable social discount rate that can be applied to environmental investment projects. Taking into account recent economic situations, the social discount rate is currently being estimated at between 2.9 ~ 4.9%. Also, this paper used preliminary feasibility studies that took place so far, to analyze the standard pattern of benefit generation. This revealed that alterations in social discount rates can bring significant changes in economic feasibility test results. Simulation results showed that roughly 6% of B/C ratios could be increased by 1%p. resulting in a decrease in social discount rates. Also if we use hyperbolic discount rates, instead of using the current singular rate, there would be a meaningful increase in the benefits for the future generation.