The optimal carbon tax mechanism for managing carbon emissions

Along Pigouvian lines, the carbon tax not only exceeds the carbon emission damage imposed on society, but ignores the potential cost from deliberate carbon abatement, which in turn challenges the stability and optimality of the Pigouvian solution. For correcting these distortions, this paper amends the standard Pigouvian version by using piecewise tax functions to approximate the social damage curve of carbon emissions. An optimal carbon tax mechanism is designed, where the tax is endogenously determined from social welfare maximization. With the help of a modification instrument, the carbon tax corrects emitters’ non-optimal individual decision and the social optimum is implemented efficiently. How to put the carbon tax into practice is examined under both the deterministic and stochastic modeling settings. In both cases, we demonstrate the structure and effectiveness of the carbon tax in detail. Moreover, a flexible adjustment tax scheme is proposed, which may produce the double-dividend effect that reduces carbon emissions and relieves financial burden of carbon abatement simultaneously. These may improve the application of market-based carbon-reducing tools in public management and pollution regulation.