Plug-in Hybrid electric Cars Pollute Nearly as Much as Petrol Cars, Report Finds

PHEVs release almost five times more planet-heating emissions than official figures indicate, as per a new report.

Growing Gap In Official and Real-World Emissions

Data reveals that PHEVs emit just 19% lower CO₂ than conventional gas and diesel cars, based on analysis conducted by a advocacy organization. That contrasts sharply with lab estimates, which assumed a three-quarters decrease in emissions.

Analysts examined information from onboard energy use meters of 800,000 cars sold in Europe between 2021 and 2023. The team discovered that actual CO₂ output from PHEVs in 2023 were nearly five times higher than lab figures, increased from three and a half times in 2021.

“Real-world emissions are rising, while lab-reported figures are decreasing,” said a lead researcher participating in the report. “This gap is growing and poses a significant issue. As a result, PHEVs pollute almost as heavily as petrol vehicles.”

Key Factors Driving the Emissions Gap

Analysts attributed most of the difference to overestimates of the “utility factor” – the ratio of kilometers driven in electric power compared to total distance. They found that just a quarter of travel was done in EV mode, while lab estimates suggested 84%.

Additionally, when running in EV mode, emission amounts were well above lab projections. That happened because EV motors were insufficiently powerful enough to operate independently, resulting to engines using fossil fuels for nearly one-third of the travel covered in EV mode.

Regulatory and Economic Implications

According to calculations, the lowballing of PHEV CO2 output enabled several major carmaker companies to escape more than €5bn in fines between 2021 and 2023, by artificially easing compliance with European Union fleet-average CO₂ targets.

Furthermore, drivers of PHEVs would spend approximately €500 more per year in running costs than would be estimated under lab tests.

“The strong statements that manufacturers like to make about their plug-in hybrid vehicles are obviously way off the truth,” stated a automotive analyst. “Buyers are being duped into believing that by buying a PHEV, they are benefiting the planet and cutting money. Actually, PHEVs are little improved than standard gas and diesel vehicles in terms of fuel consumption, CO₂ emissions, and operating costs.”

Political Discussion and Automotive Pressure

Hybrid vehicles have recently been drawn again into policy discussions as automakers have lobbied the EU to weaken CO₂ standards. A proposed prohibition on new combustion engine cars in 2035 has faced heavy pressure from the car industry and opposition from member states with large car industries.

Several senior politicians have proposed PHEVs as a potential “flexibility” option to introduce in the legislation.

An independent energy policy specialist, who was not involved with the research, called the analysis a “very useful addition” after a long period in which parts of the automotive sector claimed there was too little data to properly assess actual emissions.

“These findings show, without question, that the difference between lab and real-world PHEV energy use and CO₂ emissions is much, much greater than for gasoline or conventional cars,” the expert said. “Any regulatory adjustments regarding PHEVs should be made with extreme care and in the light of this evidence.”