Plug-in Hybrid Vehicles Emit Almost as Heavily as Petrol Vehicles, Study Reveals

Plug-in hybrid electric vehicles emit nearly five times greater planet-heating pollution than official figures show, as per a new analysis.

Widening Gap Between Lab and Real-World CO2 Output

Statistics shows that PHEVs emit only 19% lower CO₂ than conventional gas and diesel cars, according to analysis conducted by a non-profit organization. That contrasts significantly with laboratory estimates, which assumed a 75% decrease in pollution.

Analysts examined information from in-vehicle fuel consumption meters of 800,000 cars sold in the EU from 2021 and 2023. They found that actual CO₂ output from PHEVs in 2023 were 4.9 times higher than lab estimates, increased from three and a half times in 2021.

“Actual emissions are rising, while official figures are decreasing,” said a senior researcher involved in the study. “This gap is growing and creates a significant issue. Consequently, PHEVs emit nearly as much as gasoline vehicles.”

Key Reasons Behind the Emissions Gap

Researchers linked the majority of the gap to inflated estimates of the “utility factor” – the ratio of miles travelled in battery mode compared to total mileage. The team determined that just 27% of travel was done in EV mode, while lab assumptions suggested over four-fifths.

Even, when running in EV mode, emission amounts were well above official estimates. This happened because electric motors were insufficiently powerful sufficient to function alone, resulting to combustion motors burning gasoline for nearly one-third of the distance covered in electric mode.

Policy and Economic Implications

According to calculations, the underestimation of PHEV CO2 output enabled four major automaker groups to avoid more than €5bn in fines between 2021 and 2023, by falsely easing compliance with European Union fleet-average CO₂ targets.

Additionally, drivers of PHEVs would pay approximately €500 extra annually in running costs than would be assumed under laboratory tests.

“The bold claims that automakers like to make about their plug-in hybrid vehicles are obviously far from the mark,” stated a automotive analyst. “Buyers are being duped into believing that by purchasing a PHEV, they are helping the planet and cutting money. Actually, PHEVs are little improved than standard gas and diesel cars in terms of fuel consumption, CO₂ production, and operating expenses.”

Political Debate and Automotive Lobbying

Hybrid cars have lately been drawn back into political discussions as automakers have lobbied the European Union to relax CO₂ targets. A planned ban on new internal combustion vehicles in 2035 has faced heavy pressure from the car industry and opposition from member states with significant automotive manufacturing.

Several senior officials have suggested plug-in hybrids as a possible “compromise” solution to introduce in the legislation.

One independent energy economics specialist, who was not involved with the study, described the report a “highly valuable addition” after years in which parts of the car sector argued there was insufficient information to accurately evaluate actual CO2 output.

“The results demonstrate, beyond any doubt, that the difference in official and actual PHEV energy use and CO₂ output is much, much greater than for petrol or conventional vehicles,” the expert stated. “Any policy changes regarding PHEVs should be implemented with utmost caution and considering this data.”