“The influence of electrification scenarios in road transport on the climate targets”

The transport sector accounts for about 22% of Germany's greenhouse gas (GHG) emissions and is amongst the most difficult parts of the energy system to decarbonize. The most commonly discussed options for the transport sector are the electrification of drivetrains and the use of renewable fuels. Especially in road transport, the future development depends on millions of individual purchase decisions, which introduces significant uncertainty regarding the speed and extent of electrification. Against this background, this study generates possible ramp-up curves for battery electric vehicles (BEV) using well-established diffusion models, historical vehicle stock data, data for BEV in Germany and literature expectations for future development trends concerning the electrification in road transport. These ramp-up curves are integrated into the vehicle stock in order to investigate the impact of different ramp-ups of BEV on the legal framework and GHG emission reduction obligations in the transport sector. The results show that the energy demand (and its composition) of the sector is strongly influenced by the degree of electrification in road transport. However, even with high shares of BEV in the vehicle stock, a significant use of renewable fuels will be necessary to meet the regulatory framework conditions under the Renewable Energy Directive (RED), the German GHG quota and the German Climate Change Act (KSG) in order to realize both blending quotas and absolute GHG emission reductions according to the German sector targets for transport. • Plausible BEV ramp-up trajectories derived from diffusion models and fleet data. • Ramp-up differences strongly affect renewable fuel demand and compliance outcomes. • Fast electrification lowers (renewable) fuel demand and reduces compliance risks. • Even high BEV shares require renewable fuels to meet interim climate targets. • Misalignment remains between relative quota frameworks and absolute KSG targets.