Full Breakdown
Plug-in Hybrid Emissions Far Exceed Official EU Ratings, Prompting Industry Pushback
9/9/2026, 12:09:01 AM
Core Event – Real-World Emissions vs. Official Ratings
Transport & Environment (T&E) analyzed onboard fuel-consumption data from 220,000 plug-in hybrid electric vehicles (PHEVs) registered in the European Union. The analysis shows that PHEVs registered in 2024 emitted an average 145 g CO2 / km, while the official EU test rating for the same fleet was 24 g CO2 / km – a gap of roughly six times. For 2023 registrations the real-world average was 138 g CO2 / km against an official 28 g CO2 / km, indicating the discrepancy widened from five-fold to six-fold in one year.
Background & Context – Utility Factor and EU Testing Regime
EU emissions testing for PHEVs relies on a “utility factor” that estimates the proportion of driving performed on electric power. The higher the assumed electric use, the lower the calculated CO2 rating. Since many owners rarely plug in their vehicles, the utility factor underestimates actual tailpipe emissions. The EU began tightening the utility-factor assumption in 2025 and plans a further correction in 2027 to bring official figures closer to real-world performance.
Data & Statistics – Emissions Gaps and Trends
- 2024 real-world emissions: 145 g CO2 / km (T&E analysis).
- 2024 official rating: 24 g CO2 / km.
- 2023 real-world emissions: 138 g CO2 / km.
- 2023 official rating: 28 g CO2 / km.
- Change 2023->2024: Real-world emissions rose 5 %; official ratings fell ?15 %.
- Compared with average conventional petrol/diesel cars (169 g CO2 / km), PHEVs were only 14 % cleaner in 2024, down from a 17 % advantage the previous year.
Official Statements & Responses – EU Plans and Industry Positioning
The European Commission has announced that the 2027 utility-factor correction will be applied to all new PHEV registrations, aiming to align official CO2 values with observed driving patterns. Automakers and their representative bodies argue that the correction would “harm the auto industry” and delay investment in fully electric vehicles. The European Automobile Manufacturers’ Association (ACEA) has formally requested that the upcoming correction be cancelled.
Criticism & Opposition – Lobbying Against Stricter Utility Factors
Automakers have mounted a coordinated lobbying effort to weaken the 2027 utility-factor update. ACEA, representing the industry, contends that the correction would “make PHEVs a tougher sell” and jeopardize fleet-wide CO2 compliance. Power-train supplier Horse – a joint venture involving Renault, Geely and Aramco – published a paper in March warning that tighter utility-factor requirements would “harm the auto industry.” T&E notes that weakening the rule could allow manufacturers to continue receiving “extra credit” for marginally greener-on-paper PHEVs, thereby postponing the transition to pure electric models.
Verbatim Quotes
- “Plug-in hybrids are one of the auto industry’s greatest greenwashing stunts,” — Lucien Mathieu, T&E’s cars director
What’s Next – Legislative Timeline
The EU Council is scheduled to debate the utility-factor file on October 12. A parliamentary vote on the matter is expected in November. The outcome will determine whether the 2027 correction proceeds as planned or is altered in response to industry lobbying.
