Supply-side elasticities as determinants of optimal carbon taxation
研究开放经济中单边碳税如何根据污染性投入品的供给价格弹性来设定，发现供给弹性越低的投入品应被课以更高税率以减少碳泄漏。
Consider an open economy with two polluting production inputs, whose policymakers decide to implement a unilateral carbon tax on the use of the inputs. The one-sided policy introduces a leakage externality whose magnitude depends on the price responses of the polluting inputs. We show that the optimal tax on a polluting input decreases when the relative supply-price elasticity increases. The intuition is that inputs with low supply-price elasticities experience larger price decreases in response to taxes, which incentivises the producers in the non-taxing country to use more of them. The policymaker avoids this by taxing the elastic inputs the most. • Differentiated unilateral taxes on polluting inputs (such as oil and gas) can reduce carbon leakage. • Optimal unilateral carbon taxes increase in supply-price elasticities of pollutants. • Uniform unilateral taxes could increase global pollution by lowering prices of inelastic inputs.