Plug in Hybrid electric Vehicles Pollute Nearly as Heavily as Petrol Vehicles, Study Finds
Plug-in hybrid electric vehicles emit almost 5x greater planet-heating emissions than lab-reported figures indicate, according to a new report.
Widening Discrepancy In Lab and Real-World Emissions
Data reveals that PHEVs release only 19% lower CO2 than traditional petrol and diesel cars, according to research conducted by a non-profit organization. This contrasts sharply with lab tests, which suggested a three-quarters reduction in pollution.
Analysts studied data from onboard energy use meters of 800,000 cars registered in the EU from 2021 and 2023. They found that actual CO2 emissions from PHEVs in 2023 were nearly five times higher than official estimates, increased from 3.5 times in 2021.
“Actual CO2 output are increasing, while lab-reported emissions are decreasing,” said a senior analyst participating in the report. “That discrepancy is widening and poses a serious problem. Consequently, PHEVs pollute almost as heavily as petrol vehicles.”
Key Factors Behind the Discrepancy
Researchers linked most of the difference to overestimates of the “electric driving share” – the ratio of kilometers driven in battery mode relative to total distance. The team found that just a quarter of travel was done in EV mode, whereas official estimates suggested over four-fifths.
Additionally, when operating in electric mode, emission amounts were well above official projections. That occurred because electric motors were insufficiently powerful enough to function independently, resulting to combustion motors using fossil fuels for nearly a third of the distance covered in electric mode.
Regulatory and Economic Implications
Based on calculations, the lowballing of PHEV CO2 output allowed several major carmaker companies to escape over €5bn in penalties between 2021 and 2023, by artificially easing adherence with European Union average fleet CO2 standards.
Furthermore, owners of PHEVs could pay about €500 more annually in operating costs than is estimated under laboratory conditions.
“The bold claims that manufacturers often promote about their plug-in hybrid cars are obviously way off the mark,” stated a automotive analyst. “Buyers are being misled into believing that by buying a PHEV, they are benefiting the planet and cutting money. Actually, PHEVs are only slightly better than standard petrol and diesel cars in terms of energy use, CO2 emissions, and operating expenses.”
Political Debate and Industry Pressure
Hybrid cars have recently been brought again into political discussions as carmakers have lobbied the European Union to relax CO2 targets. A proposed prohibition on new combustion engine cars in 2035 has faced intense pressure from the car sector and resistance from EU countries with significant automotive manufacturing.
Several high-level politicians have proposed plug-in hybrids as a potential “flexibility” option to introduce in the legislation.
One independent energy economics expert, who was unaffiliated with the research, described the analysis a “highly valuable addition” after years in which segments of the car sector claimed there was insufficient data to accurately evaluate actual emissions.
“The results demonstrate, without question, that the gap in lab and actual PHEV energy use and CO2 emissions is significantly greater than for petrol or conventional vehicles,” they stated. “Any regulatory adjustments regarding PHEVs should be implemented with utmost care and in the light of this evidence.”
