🔗 Share this article Plug-in Hybrid Cars Emit Almost as Much as Petrol Cars, Study Reveals Plug-in hybrid cars produce almost five times more global warming pollution than lab-reported data show, according to a new analysis. Growing Gap Between Official and Real-World Emissions Data shows that PHEVs release just 19% less CO2 than conventional gas and diesel cars, based on analysis conducted by a non-profit organization. This differs sharply with laboratory estimates, which suggested a three-quarters decrease in pollution. Researchers examined data from in-vehicle fuel consumption monitors of 800,000 vehicles registered in the EU between 2021 and 2023. The team found that real-world CO2 emissions from PHEVs in 2023 were 4.9 times higher than lab estimates, increased from three and a half times in 2021. “Actual CO2 output are increasing, while official figures are decreasing,” said a senior researcher involved in the report. “This gap is widening and creates a serious issue. As a result, PHEVs emit almost as much as petrol vehicles.” Key Reasons Behind the Discrepancy Researchers linked the majority of the gap to overestimates of the “electric driving share” – the percentage of kilometers travelled in electric mode compared to overall distance. The team found that only 27% of driving was done in electric mode, whereas lab assumptions assumed over four-fifths. Additionally, when operating in electric mode, pollution levels were significantly higher than official estimates. This happened because electric motors were insufficiently powerful sufficient to function alone, resulting to combustion motors burning gasoline for almost one-third of the travel covered in electric mode. Policy and Financial Consequences According to estimates, the underestimation of PHEV emissions allowed several major carmaker groups to avoid more than €5bn in fines from 2021 and 2023, by falsely simplifying adherence with EU average fleet CO2 targets. Additionally, drivers of PHEVs would pay approximately €500 more annually in operating costs than is assumed under laboratory tests. “The strong statements that automakers often promote about their plug-in hybrid vehicles are clearly far from the truth,” commented a transport analyst. “Buyers are being misled into believing that by purchasing a PHEV, they are helping the planet and saving costs. In reality, PHEVs are little better than regular gas and diesel cars in terms of energy use, CO2 emissions, and operating expenses.” Policy Discussion and Industry Lobbying Hybrid vehicles have recently been drawn again into political debates as carmakers have pressed the EU to relax CO2 standards. A planned ban on sales of new combustion engine cars in 2035 has faced intense lobbying from the car sector and resistance from EU countries with significant automotive manufacturing. Several high-level politicians have suggested PHEVs as a potential “flexibility” solution to include in the legislation. An independent energy policy specialist, who was unaffiliated with the study, called the analysis a “very useful contribution” after a long period in which parts of the automotive sector argued there was insufficient information to properly evaluate actual emissions. “These findings show, beyond any doubt, that the difference in lab and actual PHEV fuel consumption and CO2 output is much, much larger than for gasoline or conventional vehicles,” they stated. “All policy adjustments concerning PHEVs should be implemented with extreme caution and considering that evidence.”