🔗 Share this article

PHEVs emit nearly 5x greater planet-heating emissions than lab-reported figures show, as per a recent report.

Widening Gap Between Official and Actual Emissions

Data shows that PHEVs emit just 19% lower CO₂ than conventional gas and diesel vehicles, based on analysis carried out by a non-profit organization. That contrasts sharply with lab estimates, which suggested a three-quarters decrease in pollution.

Researchers examined data from onboard fuel consumption meters of eight hundred thousand vehicles sold in the EU between 2021 and 2023. They found that actual CO₂ emissions from PHEVs in 2023 were nearly five times higher than official figures, up from three and a half times in 2021.

“Real-world emissions are increasing, while official figures are decreasing,” stated a senior researcher involved in the study. “That gap is growing and creates a significant issue. Consequently, PHEVs emit almost as heavily as gasoline vehicles.”

Key Reasons Behind the Emissions Gap

Analysts attributed the majority of the gap to overestimates of the “electric driving share” – the ratio of miles travelled in electric mode relative to total distance. The team determined that just a quarter of driving was done in EV mode, whereas official assumptions assumed 84%.

Even, when running in electric mode, pollution amounts were significantly higher than official projections. That happened because EV motors were not strong sufficient to function alone, leading to engines burning fossil fuels for nearly a third of the travel completed in electric mode.

Regulatory and Economic Consequences

According to estimates, the underestimation of PHEV emissions allowed four large carmaker groups to escape over €5bn in fines from 2021 and 2023, by artificially simplifying adherence with EU fleet-average CO₂ standards.

Furthermore, owners of PHEVs could spend approximately €500 more annually in running expenses than would be assumed under lab tests.

“The bold statements that manufacturers like to make about their plug-in hybrid cars are clearly way off the mark,” commented a automotive expert. “Buyers are being duped into believing that by buying a PHEV, they are benefiting the environment and cutting money. Actually, PHEVs are only slightly better than regular petrol and diesel cars in terms of energy use, CO₂ production, and operating costs.”

Political Debate and Automotive Pressure

Hybrid vehicles have lately been drawn back into policy discussions as automakers have lobbied the European Union to weaken CO₂ standards. A proposed prohibition on sales of new internal combustion cars in 2035 has faced heavy pressure from the car sector and opposition from EU countries with significant automotive industries.

Several high-level officials have suggested plug-in hybrids as a potential “compromise” option to introduce in the regulation.

An external energy economics specialist, who was not involved with the study, called the analysis a “very useful addition” after years in which parts of the automotive industry claimed there was too little information to accurately assess actual emissions.

“These findings show, beyond any doubt, that the gap in official and actual PHEV energy use and CO₂ emissions is significantly greater than for gasoline or conventional vehicles,” they said. “All regulatory adjustments regarding PHEVs should be made with extreme caution and considering that evidence.”