Overview
- Telemetry from roughly one million PHEVs built between 2021 and 2023 shows average real‑world fuel use of about 5.9 litres per 100km, around three times higher than type‑approval figures.
- The analysis estimates real‑world CO2 emissions are three to five times higher than manufacturers advertise.
- Lead researcher Patrick Plötz says frequent switching between electric and combustion drive means the engine engages more than expected, especially in discharge mode.
- Results vary widely by model, with some lower‑cost PHEVs from brands such as Kia, Toyota, Ford and Renault using under 1 litre/100km, while Porsche hybrids average around 7 litres/100km.
- Automakers and the SMMT cite differing usage patterns and WLTP compliance, as Fraunhofer urges regulators to tighten measurement procedures and consider measures like display transparency and mandatory charging intervals.