New infrastructure projects may affect CO2 emissions and, thus, cost benefit analyses for these projects require a value to apply for CO2. This may be based on the marginal social cost of emissions or on the carbon price resulting from present and future policies. This paper argues that both...

The standard framework in which economists evaluate environmental policies is cost-benefit analysis, so policy debates usually focus on the expected flows of costs and benefits, or on the choice of discount rate. But this can be misleading when there is uncertainty over future outcomes, when...