Road transport electrification – Is timing everything? Implications of emissions analysis’ outcomes for climate and air policy

Abstract Road transport electrification will form a substantial part of international strategies to mitigate greenhouse gas and air pollutant emissions. Targets for electrification of the road-transport sector are often set as the number of electric vehicles to be operating within the fleet by a certain date. There is recognition that timeframes for these transitions matter, but research focuses more on total numbers and upstream power considerations. Outcomes for varied uptake rates are often absent. This analysis builds multiple future electric vehicle uptake scenarios from granular fleet and activity data, using Ireland as the case study. The analysis quantifies the degrees to which the scale of ambition, early or late penetration, and a focus on passenger cars or goods vehicles affects emission outcomes. Results show that a faster electric vehicle uptake more than doubles the cumulative GHG emissions reduction by 2030. E-van and E-truck transitions are also particularly important. Impacts on air pollution are modest due to the continued improvement of Euro-standards. Broader vehicle choice, information campaigns, infrastructure investment, and fiscal policy incentives can all accelerate the rates of fleet change at a cost. Policy must therefore choose where, when, and how much to intervene with incentives, weighing the potential for positive emission outcomes against the level and timing of investment and supports to the market.