Plug in Hybrid Cars Pollute Almost as Much as Petrol Cars, Report Finds

Plug-in hybrid electric vehicles produce almost five times more global warming pollution than official figures indicate, as per a new analysis.

Widening Gap Between Official and Actual Emissions

Data reveals that PHEVs release just 19% less CO₂ than traditional petrol and diesel cars, according to research conducted by a advocacy organization. This differs significantly with laboratory estimates, which assumed a three-quarters decrease in emissions.

Researchers studied data from onboard fuel consumption meters of eight hundred thousand vehicles sold in Europe between 2021 and 2023. They discovered that actual CO₂ output from PHEVs in 2023 were 4.9 times greater than lab figures, up from 3.5 times in 2021.

“Actual CO2 output are increasing, while lab-reported figures are decreasing,” stated a senior analyst involved in the report. “That discrepancy is widening and poses a serious problem. As a result, PHEVs emit almost as much as petrol cars.”

Key Factors Driving the Emissions Gap

Analysts linked the majority of the difference to overestimates of the “electric driving share” – the ratio of kilometers driven in battery power relative to overall mileage. They found that just a quarter of travel was completed in EV mode, whereas official assumptions assumed 84%.

Even, when operating in electric mode, emission levels were significantly higher than official estimates. This occurred because EV motors were insufficiently powerful enough to function independently, resulting to engines burning gasoline for almost one-third of the travel completed in electric mode.

Policy and Financial Consequences

According to estimates, the underestimation of PHEV emissions allowed several large carmaker groups to escape more than €5bn in penalties between 2021 and 2023, by falsely simplifying compliance with European Union fleet-average CO₂ targets.

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

“The bold claims that automakers often promote about their PHEV vehicles are obviously way off the mark,” commented a transport analyst. “Buyers are being misled into believing that by purchasing a PHEV, they are helping the planet and saving money. In reality, PHEVs are little better than regular gas and diesel vehicles in terms of fuel consumption, CO₂ emissions, and operating costs.”

Political Discussion and Automotive Pressure

Plug-in hybrid cars have lately been drawn back into political discussions as carmakers have lobbied the EU to weaken CO₂ targets. A proposed ban on new combustion engine vehicles in 2035 has faced intense pressure from the car sector and resistance from member states with large car manufacturing.

Some senior politicians have proposed PHEVs as a potential “flexibility” option to include in the regulation.

An independent energy economics expert, who was not involved with the study, called the report a “highly valuable addition” after a long period in which segments of the car sector claimed there was too little data to properly assess actual CO2 output.

“These findings demonstrate, without question, that the gap between lab and actual PHEV energy use and CO₂ output is significantly larger than for gasoline or conventional cars,” the expert said. “All policy adjustments concerning PHEVs should be made with extreme caution and considering this evidence.”