Plug-in Hybrid electric Vehicles Emit Almost as Heavily as Gasoline Vehicles, Report Finds
Plug-in hybrid cars produce almost 5x more planet-heating emissions than lab-reported figures show, according to a recent analysis.
Growing Gap In Lab and Actual Emissions
Data reveals that PHEVs emit just 19% less CO2 than conventional petrol and diesel vehicles, according to research conducted by a non-profit group. That differs significantly with lab tests, which assumed a 75% decrease in emissions.
Analysts studied data from onboard fuel consumption meters of eight hundred thousand cars sold in the EU from 2021 and 2023. The team found that real-world CO2 emissions from PHEVs in 2023 were 4.9 times greater than official figures, up from 3.5 times in 2021.
“Actual CO2 output are increasing, while official figures are falling,” said a lead researcher participating in the study. “That discrepancy is growing and creates a significant problem. Consequently, PHEVs emit almost as heavily as gasoline vehicles.”
Key Reasons Behind the Emissions Gap
Researchers linked the majority of the gap to inflated estimates of the “utility factor” – the percentage of kilometers travelled in battery mode relative to overall mileage. They determined that only a quarter of driving was done in EV mode, whereas official estimates suggested 84%.
Even, when running in EV mode, emission amounts were well above lab projections. That happened because electric motors were insufficiently powerful enough to function alone, resulting to engines using fossil fuels for almost a third of the distance completed in electric mode.
Policy and Economic Consequences
According to calculations, the underestimation of PHEV CO2 output allowed several major automaker companies to avoid more than €5bn in fines between 2021 and 2023, by falsely simplifying adherence with European Union average fleet CO2 standards.
Additionally, owners of PHEVs could pay about €500 extra per year in operating costs than is estimated under lab tests.
“The strong claims that manufacturers like to make about their PHEV vehicles are clearly far from the truth,” stated a automotive analyst. “Consumers are being duped into believing that by buying a PHEV, they are helping the environment and cutting costs. Actually, PHEVs are little improved than standard petrol and diesel vehicles in terms of fuel consumption, CO2 emissions, and operating costs.”
Political Debate and Industry Pressure
Hybrid vehicles have recently been drawn again into political debates as carmakers have lobbied the EU to relax CO2 targets. A proposed prohibition on sales of new combustion engine cars in 2035 has faced heavy pressure from the automotive sector and opposition from EU countries with significant car industries.
Some high-level officials have proposed PHEVs as a potential “compromise” solution to introduce in the legislation.
One independent energy policy expert, who was not involved with the study, called the analysis a “highly valuable addition” after a long period in which parts of the automotive industry claimed there was too little information to accurately evaluate actual emissions.
“These findings show, beyond any doubt, that the difference between lab and actual PHEV energy use and CO2 output is much, much larger than for petrol or diesel cars,” they stated. “All policy adjustments regarding PHEVs should be implemented with utmost caution and in the light of that evidence.”
