Carbon price and optimal extraction of a polluting fossil fuel with restricted carbon capture

Abstract

Among technological options to mitigate greenhouse gas (GHG) emissions, Carbon Capture and Storage technology (CCS) seems particularly promising. This technology allows to keep on extracting polluting fossil fuels without drastically increasing CO2 atmospheric concentration. We examine here a two-sector model with two primary energy resources, a polluting exhaustible resource and an expensive carbon-free renewable resource, in which an environmental regulation is imposed through a cap on the atmospheric carbon stock. We assume that only the emissions from one sector can be captured. Previous literature, based on one-sector models in which all emissions are capturable, finds that CCS technology should not be used before the threshold has been reached. We find that, when technical constraints make it impossible to capture emissions from both sectors, this result does not always hold. CCS technology should be used before the ceiling is reached if non capturable emissions are large enough. In that case, we find that energy prices paths must differ between sectors reflecting the difference of social cost of the resource according to its use. Numerical exercise show that, when the ceiling is set at 450ppm CO2, the initial carbon tax should equal 52$/tCO2 and that using CCS before the ceiling is optimal. ; Parmi les technologies disponibles pour lutter contre l'accumulation des gaz à effet de serre dans l'atmosphère, la capture et la séquestration du CO2 semble particulièrement prometteuse. Elle permet de déconnecter le flux des émissions anthropiques de CO2 de l'utilisation des combustibles fossiles. Nous proposons un modèle à deux secteurs dans lequel deux sources d'énergie primaire sont disponibles : une ressource épuisable dont l'utilisation génère du CO2 et une ressource renouvelable "propre". Une régulation environnementale est introduite sous la forme d'un plafond que la concentration de CO2 dans l'atmosphère ne doit pas dépasser. Nous supposons que seules les émissions provenant d'un secteur peuvent être ...