Politiques pro-biocarburants et climatique américaines : impact sur les choix énergétiques du Brésil et des Etats-Unis et bilan carbone

In this paper, a partial trade equilibrium model is developed to explore the impacts of US energy policies on the use and trade of first-generation biofuels (ethanol) and second-generation biofuels (ligno-cellulosic ethanol) in the United-States and Brazil. In addition, we investigate their impacts on direct and indirect carbon emissions. The first policy is the biofuels mandatory target. The second defines a cap on carbon emissions. Our study reveals that the biofuels mandatory target encourages ligno-cellulosic ethanol production, reductions in carbon emissions being marginal. The second policy increases energy prices leading to a decrease in energy consumption as well as in direct carbon emissions. However, this policy has a significant impact on deforestation in Brazil resulting in a rise in indirect carbon emissions. The biofuels subsidy needed to reach the mandatory target amounts to US $ 1.1 per gallon. The US carbon tax reaches US $ 120 per ton equivalent carbon. A differential tax is imposed on gasoline, ethanol and ligno-cellulosic ethanol based on the carbon content. It is respectively equal to US $ 0.38, US $ 0.204 and US $ 0.024.