Overview
- The International Council on Clean Transportation published an OBDFM analysis on Friday, June 5, 2026, reporting that plug‑in hybrid vehicles emitted on average 401% more CO2 in 2023 than their WLTP type‑approval figures indicated.
- The finding is based on On‑Board Fuel Consumption Monitoring data, a system mandatory for new petrol and hybrid cars since 2021 that records continuous fuel and energy use and can be accessed by authorities.
- ICCT says the core problem is a WLTP testing assumption called the Utility Factor that overestimates how much PHEV driving is electric because many owners, especially company‑car users, do not regularly charge their batteries.
- To fix the gap the ICCT recommends updating Utility Factor curves, extending on‑board consumption reporting (OBFCM) to all Euro‑7 electric vehicles from November 2026, and introducing an automatic EU correction mechanism for manufacturers from 2027.
- Automakers have proposed technical penalties for drivers who never charge, a move that has intensified public worries about fairness and vehicle data privacy and could push regulators to tighten fleet targets and subsidy rules.