Role of hybrid vehicles in EU fleet mix questionable: very high CO2 emissions

Because plug-in hybrid vehicles (PHEVs) combine an electric drive with a combustion engine, they are promoted as a transitional technology on the road to climate-neutral mobility in EU climate policy. However, real-world consumption data from around 850,000 vehicles across Europe shows that, on average, they are rarely charged, the combustion engine is used too often, and even in mainly electric mode, fuel consumption is considerable. With this level of use, new PHEV registrations after 2035 are not compatible with climate protection targets in transport.

The automotive industry is currently calling for plug-in hybrid vehicles (PHEVs) to be excluded from the planned ban on new registrations of vehicles with combustion engines from 2035. The EU Commission plans to reassess their role in the European fleet mix and intends to readjust the basis for calculating CO₂ emissions from PHEVs from 2027. This is because its previous assessment of the “utility factor” was too high. This key figure indicates the proportion of the distance driven predominantly on electric power and is used to calculate official emissions in the context of EU fleet limits. According to the analysis prepared by Ariadne consortium partner Fraunhofer Institute for Systems and Innovation Research ISI, all manufacturers exceed the official type approval values of 1.0 to 1.7 liters per 100 kilometers by 300 to 500 percent. The actual real-world fuel consumption of PHEVs registered between 2021 and 2023 averaged around 6 liters per 100 kilometers.

New registrations of plug-in hybrid vehicles powered by fossil fuels after 2035 in the EU would run counter to current ambitions to reduce CO₂ emissions. This would make the EU’s goal of climate neutrality by 2050 even more unlikely. The researchers therefore recommend that plug-in hybrid vehicles should only be approved as a transitional technology under very strict conditions. Such regulation would be possible for the first time thanks to the widespread availability of empirical consumption data from all passenger car manufacturers. It should be based on best practice examples from North America and limit the share of these vehicles to 5 to 10 percent of the new car fleet for a few years. It could also stipulate that PHEVs must not emit more than 10 grams of CO₂ per kilometer in real-world driving and impose penalties on manufacturers who fail to comply. Strict technical requirements should ensure that electric operation is clearly prioritized: specifically, this would mean a minimum range of at least 100 kilometers in electric mode and purely electric operation even under demanding conditions.