We obtain a formula for how non-renewable resources should be taxed when governments need to collect commodity tax revenues: This tax rule is an augmented, dynamic version of the standard Ramsey inverse elasticity rule, which requires a novel interpretation of the optimal commodity tax distortions. We show the following results. First, flows of non-renewable resources should be taxed at higher rates than otherwise identical conventional commodities. Second, our rule is compatible with the variety of observed resource tax systems, ranging from systems in which firms finance reserve production and are paid back by future after-tax extraction rents to the extreme case of nationalized industries. Third, optimal non-renewable resource taxation distorts developed reserves, which are reduced, and their depletion, which is slowed down. These distortions go in the same direction as those prescribed for resolution of the climate externality. Our formula can be directly used to indicate how carbon taxation should be increased in the presence of public-revenue needs, as illustrated in a numerical example.
JEL classification: Q31; Q38; H21
Keywords: Optimal commodity taxation; Inverse elasticity rule; Non-renewable resources; Supply elasticity; Carbon taxation