Carbon leakages: a general equilibrium view

The effectiveness of unilateral action to curb carbon emissions has been dismissed because of possible "carbon leakages", this referring to the rise of emissions in non-participating countries. This paper offers a general equilibrium (GE) exploration of the key mechanisms and factors underlying the size of carbon leakages. We developed a two-region, two-goods simplified GE framework, incorporating three types of fossil fuels (coal, oil and low-carbon energy), international trade and capital mobility. The model was designed to make tractable extensive multidimensional sensitivity analysis. The results suggest that the coal supply elasticity plays a critical role, while substitution elasticities between traded goods and international capital mobility appear relatively less influential. The shape of the production function also matters for the size of the leakages. Confirming the results obtained with large computable GE models, for a wide range of parameters' values, carbon leakages appear to be small. Therefore, the argument that unilateral carbon abatement action taken by a large group of countries (such as the Annex 1 group) is flawed by significant carbon leakages is not supported by our sensitivity analysis. The likelihood of small leakages favours in fact the formation of a worldwide coalition to stabilise climate change.