🔗 Share this article Plug-in Hybrid electric Cars Emit Nearly as Much as Gasoline Vehicles, Study Reveals Plug-in hybrid cars produce almost five times greater planet-heating emissions than lab-reported data indicate, as per a new analysis. Widening Discrepancy Between Lab and Real-World CO2 Output Statistics shows that PHEVs emit just one-fifth less CO2 than conventional petrol and diesel cars, according to analysis carried out by a advocacy group. That contrasts sharply with lab tests, which suggested a 75% reduction in emissions. Analysts studied data from onboard energy use monitors of eight hundred thousand vehicles registered in the EU between 2021 and 2023. They discovered that real-world CO2 output from PHEVs in 2023 were nearly five times higher than lab figures, up from 3.5 times in 2021. “Actual CO2 output are rising, while official figures are decreasing,” stated a senior researcher participating in the study. “That discrepancy is widening and poses a significant issue. As a result, PHEVs pollute nearly as much as petrol vehicles.” Key Factors Behind the Emissions Gap Analysts attributed the majority of the difference to inflated estimates of the “electric driving share” – the percentage of miles driven in battery power compared to total mileage. The team found that only a quarter of driving was done in EV mode, whereas lab estimates assumed over four-fifths. Additionally, when operating in electric mode, emission levels were significantly higher than official projections. That occurred because electric motors were insufficiently powerful sufficient to operate alone, leading to engines using fossil fuels for nearly one-third of the travel covered in electric mode. Policy and Financial Implications Based on estimates, the underestimation of PHEV emissions enabled four major automaker companies to avoid more than €5bn in penalties from 2021 and 2023, by falsely easing compliance with European Union fleet-average CO2 targets. Furthermore, owners of PHEVs would pay about €500 more per year in operating costs than would be assumed under laboratory tests. “The bold statements that manufacturers often promote about their PHEV vehicles are obviously way off the truth,” stated a transport analyst. “Buyers are being misled into believing that by purchasing a PHEV, they are helping the environment and saving money. Actually, PHEVs are only slightly improved than standard petrol and diesel cars in terms of energy use, CO2 emissions, and running expenses.” Policy Debate and Industry Lobbying Plug-in hybrid cars have recently been brought again into policy debates as carmakers have pressed the European Union to weaken CO2 targets. A planned prohibition on new combustion engine vehicles in 2035 has faced heavy lobbying from the automotive industry and opposition from member states with significant car industries. Several senior politicians have suggested plug-in hybrids as a possible “flexibility” option to introduce in the legislation. One independent energy economics expert, who was unaffiliated with the study, called the analysis a “very useful addition” after a long period in which parts of the automotive sector argued there was too little data to accurately assess actual emissions. “The results demonstrate, without question, that the difference between official and real-world PHEV fuel consumption and CO2 emissions is much, much greater than for petrol or diesel vehicles,” the expert said. “All policy adjustments concerning PHEVs should be made with utmost care and in the light of this data.”