Overview
- An ICCT report published in early September 2026 shows average real‑world CO2 from plug‑in hybrid electric vehicles (PHEVs) rose from about 3.5 times the EU homologation values in 2021 to about 4.6 times in 2023.
- The study attributes the growing gap chiefly to drivers recharging PHEVs far less often than test assumptions, which leaves vehicles running on their combustion engines more than expected.
- ICCT gives a concrete example where a PHEV emits roughly 130 g CO2 per km in real use versus about 37 g per km under EU test procedures, illustrating how test assumptions understate true emissions.
- The findings strengthen calls to revise the EU method for counting PHEV emissions next year and could reduce hybrids’ value as a compliance tool while shifting market incentives toward full battery electric vehicles.
- The report builds on ICCT’s track record in vehicle emissions research and matters to drivers, manufacturers and governments because changes to rules could affect new‑car choices, maker compliance costs and national EV plans.