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

Plug-in hybrid cars produce nearly 5x greater planet-heating emissions than official figures show, as per a recent analysis.

Growing Discrepancy In Lab and Actual Emissions

Statistics reveals that PHEVs release just 19% less CO₂ than traditional petrol and diesel cars, based on analysis carried out by a non-profit group. This differs significantly with lab estimates, which assumed a three-quarters reduction in pollution.

Researchers examined information from in-vehicle energy use meters of eight hundred thousand cars sold in the EU from 2021 and 2023. They discovered that real-world CO₂ output from PHEVs in 2023 were nearly five times greater than lab figures, up from 3.5 times in 2021.

“Real-world CO2 output are increasing, while official emissions are falling,” said a senior researcher participating in the study. “This discrepancy is growing and creates a serious issue. Consequently, PHEVs emit almost as much as gasoline cars.”

Key Factors Driving the Discrepancy

Analysts attributed the majority of the difference to overestimates of the “electric driving share” – the percentage of miles travelled in electric mode relative to total distance. The team determined that just 27% of driving was done in EV mode, whereas lab estimates assumed 84%.

Additionally, when running in EV mode, emission levels were well above official projections. That occurred because electric motors were not strong enough to function independently, leading to combustion motors using fossil fuels for nearly one-third of the travel covered in EV mode.

Regulatory and Economic Implications

Based on calculations, the lowballing of PHEV CO2 output allowed four major carmaker groups to escape over €5bn in penalties from 2021 and 2023, by falsely easing compliance with European Union fleet-average CO₂ standards.

Additionally, owners of PHEVs would spend approximately €500 extra per year in running expenses than would be assumed under lab tests.

“The bold statements that automakers like to make about their PHEV cars are obviously way off the truth,” stated a transport analyst. “Buyers are being misled into thinking that by purchasing a PHEV, they are helping the planet and cutting costs. In reality, PHEVs are little improved than standard gas and diesel cars in terms of energy use, CO₂ production, and running expenses.”

Political Discussion and Automotive Pressure

Hybrid vehicles have lately been drawn back into political discussions as automakers have lobbied the EU to relax CO₂ standards. A proposed ban on sales of new combustion engine cars in 2035 has faced intense lobbying from the automotive sector and opposition from member states with significant car manufacturing.

Some high-level politicians have suggested plug-in hybrids as a possible “compromise” option to include in the regulation.

An independent energy policy specialist, who was not involved with the study, described the analysis a “very useful contribution” after years in which parts of the automotive sector argued there was too little data to accurately assess real-world CO2 output.

“These findings show, beyond any doubt, that the gap between lab and actual PHEV fuel consumption and CO₂ emissions is much, much greater than for petrol or conventional vehicles,” they said. “Any policy adjustments regarding PHEVs should be implemented with extreme care and considering that data.”