Plug in Hybrid electric Cars Pollute Almost as Much as Petrol Cars, Study Reveals

PHEVs emit nearly five times greater global warming emissions than lab-reported data show, as per a new analysis.

Growing Discrepancy In Lab and Real-World CO2 Output

Statistics reveals that PHEVs release only one-fifth less CO₂ than traditional petrol and diesel cars, according to analysis conducted by a non-profit organization. That differs significantly with lab tests, which assumed a three-quarters decrease in pollution.

Researchers examined data from onboard energy use monitors of eight hundred thousand vehicles registered in Europe between 2021 and 2023. They found that real-world CO₂ output from PHEVs in 2023 were 4.9 times greater than lab figures, up from 3.5 times in 2021.

“Real-world CO2 output are increasing, while lab-reported figures are falling,” stated a lead analyst involved in the study. “This gap is growing and poses a serious problem. As a result, PHEVs pollute nearly as much as gasoline cars.”

Key Reasons Behind the Emissions Gap

Researchers linked the majority of the difference to overestimates of the “electric driving share” – the percentage of miles travelled in electric power relative to total distance. They found that just a quarter of travel was done in electric mode, while lab estimates assumed 84%.

Even, when operating in EV mode, pollution amounts were well above official estimates. This happened because electric motors were insufficiently powerful sufficient to function alone, resulting to combustion motors burning fossil fuels for nearly a third of the distance covered in electric mode.

Regulatory and Economic Implications

Based on calculations, the lowballing of PHEV CO2 output allowed four large carmaker companies to escape more than €5bn in penalties between 2021 and 2023, by falsely simplifying adherence with European Union average fleet CO₂ standards.

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

“The bold claims that automakers often promote about their PHEV cars are obviously way off the mark,” commented a transport expert. “Buyers are being duped into believing that by buying a PHEV, they are helping the environment and saving costs. Actually, PHEVs are little improved than standard petrol and diesel cars in terms of energy use, CO₂ emissions, and operating costs.”

Policy Debate and Industry Pressure

Plug-in hybrid vehicles have lately been brought again into political debates as carmakers have pressed the EU to weaken CO₂ targets. A planned prohibition on sales of new internal combustion vehicles in 2035 has faced heavy pressure from the automotive industry and resistance from EU countries with significant automotive manufacturing.

Some high-level politicians have proposed PHEVs as a possible “compromise” solution to introduce in the legislation.

One independent energy economics expert, who was unaffiliated with the study, described the analysis a “very useful addition” after years in which segments of the automotive sector argued there was insufficient data to accurately assess real-world CO2 output.

“These findings demonstrate, without question, that the gap in official and real-world PHEV energy use and CO₂ emissions is significantly larger than for gasoline or diesel vehicles,” they stated. “Any regulatory changes regarding PHEVs should be made with extreme care and considering that evidence.”