Plug in Hybrid electric Cars Emit Almost as Heavily as Petrol Cars, Study Reveals

PHEVs emit almost 5x more global warming pollution than official data indicate, as per a recent report.

Growing Discrepancy In Official and Actual CO2 Output

Data shows that PHEVs release just 19% less CO₂ than conventional gas and diesel vehicles, according to analysis conducted by a advocacy group. That contrasts significantly with lab tests, which assumed a three-quarters reduction in emissions.

Researchers studied data from onboard fuel consumption meters of 800,000 cars registered in Europe from 2021 and 2023. The team found that real-world CO₂ emissions from PHEVs in 2023 were nearly five times higher than lab estimates, increased from three and a half times in 2021.

“Actual emissions are increasing, while lab-reported figures are falling,” said a senior researcher involved in the report. “This discrepancy is growing and poses a serious problem. Consequently, PHEVs emit almost as much as petrol vehicles.”

Key Factors Behind the Emissions Gap

Analysts attributed the majority of the gap to inflated estimates of the “utility factor” – the ratio of miles driven in electric mode relative to total distance. They determined that only 27% of travel was completed in electric mode, whereas lab assumptions suggested over four-fifths.

Additionally, when operating in EV mode, pollution levels were well above lab estimates. This occurred because EV motors were not strong sufficient to operate alone, resulting to engines using fossil fuels for almost one-third of the travel covered in electric mode.

Policy and Economic Consequences

According to estimates, the lowballing of PHEV emissions allowed several large automaker companies to escape more than €5bn in penalties from 2021 and 2023, by falsely easing adherence with EU fleet-average CO₂ standards.

Additionally, owners of PHEVs would pay approximately €500 more per year in operating costs than would be estimated under laboratory tests.

“The bold statements that automakers like to make about their plug-in hybrid cars are obviously far from the truth,” commented a automotive expert. “Consumers are being duped into thinking that by purchasing a PHEV, they are benefiting the planet and saving money. Actually, PHEVs are only slightly better than standard petrol and diesel cars in terms of energy consumption, CO₂ production, and running costs.”

Policy Debate and Industry Lobbying

Plug-in hybrid vehicles have lately been drawn back into political discussions as automakers have pressed the EU to weaken CO₂ standards. A planned ban on sales of new combustion engine cars in 2035 has faced heavy lobbying from the car industry and resistance from EU countries with significant car industries.

Some high-level officials have suggested plug-in hybrids as a possible “flexibility” option to include in the legislation.

One external energy policy specialist, who was not involved with the study, described the report a “highly valuable addition” after a long period in which segments of the automotive industry claimed there was insufficient information to properly assess real-world emissions.

“The results demonstrate, without question, that the difference in lab and real-world PHEV fuel consumption and CO₂ emissions is much, much greater than for gasoline or diesel cars,” the expert stated. “Any policy adjustments regarding PHEVs should be made with utmost care and considering this data.”