Assessment of the Marginal Emission Factor associated with Electric Vehicle Charging

Abstract

The scientific community is coming to recognize that marginal emission factors should be employed to assess the footprint of short-term interventions. There is still however disagreement on the methodologies and on the boundaries of the system to be assessed. This study argues that in an interconnected European context imports of power must be included in the calculations. Accordingly it proposes an extension of existing lean approaches taken from the literature in order to account for cross-border flows. The analysis shows that even countries with an almost carbon-free generation mix, like Switzerland, may sustain very high marginal emission factors. The application of the developed model to the case of e-mobility suggests that electric vehicles could have emissions levels comparable to modern conventional cars. The study also warns that the complexity of the system, even when simplified to a single agent, makes the effects of different charging profiles not intuitive.