🔗 Share this article

PHEVs produce nearly 5x greater planet-heating pollution than official figures indicate, according to a new report.

Widening Gap In Official and Real-World CO2 Output

Statistics shows that PHEVs emit just 19% less CO₂ than conventional gas and diesel vehicles, based on analysis conducted by a advocacy group. That differs sharply with laboratory tests, which assumed a 75% decrease in pollution.

Researchers examined information from onboard fuel consumption monitors of eight hundred thousand vehicles registered in Europe from 2021 and 2023. They discovered that real-world CO₂ emissions from PHEVs in 2023 were 4.9 times higher than lab figures, increased from three and a half times in 2021.

“Real-world emissions are increasing, while official figures are falling,” stated a senior researcher participating in the report. “This gap is widening and poses a significant problem. As a result, PHEVs emit nearly as heavily as gasoline vehicles.”

Primary Factors Driving the Discrepancy

Analysts attributed most of the difference to overestimates of the “electric driving share” – the percentage of kilometers travelled in electric mode compared to total mileage. The team determined that only a quarter of driving was done in electric mode, whereas official assumptions assumed 84%.

Additionally, when running in EV mode, emission amounts were significantly higher than official estimates. That happened because EV motors were insufficiently powerful sufficient to function independently, resulting to engines using gasoline for almost one-third of the distance completed in EV mode.

Regulatory and Economic Implications

Based on estimates, the lowballing of PHEV CO2 output enabled several major automaker groups to avoid more than €5bn in penalties between 2021 and 2023, by falsely simplifying compliance with EU average fleet CO₂ standards.

Furthermore, drivers of PHEVs would spend about €500 extra per year in operating expenses than would be assumed under lab tests.

“The strong statements that automakers often promote about their PHEV cars are clearly way off the truth,” stated a transport analyst. “Consumers are being duped into believing that by purchasing a PHEV, they are helping the planet and saving money. In reality, PHEVs are little improved than regular gas and diesel cars in terms of fuel consumption, CO₂ production, and operating expenses.”

Political Discussion and Industry Lobbying

Plug-in hybrid vehicles have recently been drawn back into policy discussions as carmakers have pressed the EU to relax CO₂ targets. A proposed prohibition on new internal combustion vehicles in 2035 has faced intense lobbying from the automotive sector and opposition from EU countries with significant automotive industries.

Several senior officials have proposed PHEVs as a possible “flexibility” option to include in the legislation.

An external energy policy expert, who was unaffiliated with the study, described the analysis a “highly valuable addition” after a long period in which segments of the car industry claimed there was too little information to accurately assess actual emissions.

“These findings show, without question, that the difference between official and actual PHEV fuel consumption and CO₂ emissions is much, much larger than for petrol or diesel vehicles,” they stated. “Any regulatory changes regarding PHEVs should be made with utmost caution and considering this evidence.”