🔗 Share this article

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

Widening Gap In Official and Real-World CO2 Output

Statistics shows that PHEVs release only one-fifth less CO₂ than conventional petrol and diesel cars, based on analysis conducted by a non-profit organization. That contrasts sharply with laboratory estimates, which suggested a 75% decrease in emissions.

Analysts studied information from in-vehicle fuel consumption meters of 800,000 vehicles sold in Europe from 2021 and 2023. They discovered that actual CO₂ emissions from PHEVs in 2023 were 4.9 times greater than lab figures, up from 3.5 times in 2021.

“Real-world CO2 output are rising, while official emissions are decreasing,” said a lead researcher involved in the study. “This gap is growing and creates a significant issue. As a result, PHEVs emit almost as heavily as petrol cars.”

Key Factors Driving the Emissions Gap

Analysts attributed the majority of the difference to inflated estimates of the “electric driving share” – the percentage of kilometers travelled in electric mode compared to total distance. They found that only 27% of travel was completed in electric mode, whereas lab estimates assumed over four-fifths.

Additionally, when operating in electric mode, emission levels were well above lab projections. That occurred because EV motors were insufficiently powerful enough to function independently, leading to engines burning gasoline for nearly a third of the travel completed in electric mode.

Policy and Economic Implications

According to estimates, the lowballing of PHEV emissions enabled several major automaker companies to escape more than €5bn in fines from 2021 and 2023, by falsely easing compliance with European Union average fleet CO₂ standards.

Furthermore, owners of PHEVs would pay approximately €500 extra annually in running expenses than would be estimated under lab tests.

“The bold claims that manufacturers like to make about their plug-in hybrid cars are obviously far from the mark,” stated a transport expert. “Buyers are being misled into believing that by buying a PHEV, they are helping the planet and saving money. Actually, PHEVs are little better than regular gas and diesel vehicles in terms of fuel consumption, CO₂ emissions, and running costs.”

Policy Discussion and Automotive Lobbying

Plug-in hybrid cars have lately been brought back into political debates as automakers have pressed the European Union to weaken CO₂ targets. A proposed prohibition on sales of new combustion engine cars in 2035 has faced heavy lobbying from the car industry and opposition from member states with significant automotive industries.

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

One external energy economics specialist, who was unaffiliated with the study, described the analysis a “highly valuable contribution” after years in which segments of the automotive sector claimed there was too little information to accurately assess real-world emissions.

“These findings show, beyond any doubt, that the gap between lab and actual PHEV energy use and CO₂ emissions is much, much greater than for gasoline or diesel cars,” they said. “Any policy adjustments regarding PHEVs should be made with extreme care and in the light of that evidence.”