Plug in Hybrid electric Cars Pollute Almost as Heavily as Gasoline Vehicles, Report Reveals

Plug-in hybrid electric vehicles produce nearly 5x more global warming pollution than lab-reported data show, according to a new report.

Growing Gap In Official and Real-World Emissions

Data reveals that PHEVs release only 19% lower CO₂ than conventional petrol and diesel cars, according to analysis carried out by a non-profit organization. This contrasts significantly with lab tests, which assumed a 75% reduction in emissions.

Analysts examined data from onboard fuel consumption meters of 800,000 vehicles sold in the EU from 2021 and 2023. They discovered that real-world CO₂ output from PHEVs in 2023 were 4.9 times higher than lab estimates, up from three and a half times in 2021.

“Real-world CO2 output are increasing, while lab-reported emissions are falling,” stated a lead researcher involved in the study. “That discrepancy is growing and creates a serious issue. As a result, PHEVs pollute nearly as much as petrol cars.”

Key Factors Behind the Emissions Gap

Analysts attributed the majority of the gap to overestimates of the “electric driving share” – the ratio of miles driven in electric power relative to total distance. They found that just a quarter of travel was done in electric mode, whereas lab assumptions suggested 84%.

Additionally, when running in electric mode, emission levels were well above official projections. That happened because EV motors were not strong sufficient to operate independently, resulting to combustion motors using gasoline for nearly a third of the travel covered in electric mode.

Regulatory and Financial Consequences

Based on calculations, the underestimation of PHEV CO2 output allowed four large carmaker companies to avoid over €5bn in fines from 2021 and 2023, by falsely easing adherence with European Union average fleet CO₂ standards.

Additionally, drivers of PHEVs would spend approximately €500 more annually in operating expenses than would be assumed under lab tests.

“The strong claims that manufacturers like to make about their plug-in hybrid vehicles are obviously way off the truth,” commented a automotive analyst. “Buyers are being duped into believing that by buying a PHEV, they are benefiting the planet and saving money. In reality, PHEVs are little improved than standard gas and diesel vehicles in terms of energy consumption, CO₂ production, and operating expenses.”

Political Discussion and Industry Pressure

Plug-in hybrid vehicles have lately been drawn again into policy debates as automakers have pressed the EU to weaken CO₂ targets. A proposed prohibition on new combustion engine vehicles in 2035 has faced heavy lobbying from the automotive sector and opposition from member states with large car manufacturing.

Some high-level officials have suggested PHEVs as a possible “flexibility” option to introduce in the legislation.

One independent energy economics expert, who was not involved with the study, called the analysis a “highly valuable addition” after years in which segments of the automotive sector claimed there was insufficient information to accurately evaluate real-world emissions.

“These findings demonstrate, without question, that the gap between official and actual PHEV energy use and CO₂ emissions is much, much larger than for gasoline or conventional vehicles,” the expert said. “Any policy adjustments concerning PHEVs should be implemented with extreme care and in the light of that data.”