New study by Fraunhofer ISI, Öko-Institut and ifeu
Fuel consumption and CO2 emissions of plug-in hybrid vehicles in real-world driving conditions
News
02/19/2026
A new study by Fraunhofer ISI, Oeko-Institut and ifeu shows that plug-in hybrid vehicles consume significantly more fuel and cause higher CO₂ emissions in real-world operation than officially stated. Evaluations of around one million vehicles reveal a considerable gap between standard and real-world values, which undermines the effectiveness of EU fleet regulations. The focus is on the so-called utility factor, which determines the proportion of electric driving mathematically. The study warns against weakening the planned adjustments and highlights possible climate policy consequences.
