🔗 Share this article

PHEVs emit nearly five times greater global warming emissions than official figures indicate, according to a recent report.

Growing Discrepancy In Official and Actual Emissions

Statistics shows that PHEVs emit only one-fifth lower CO₂ than traditional gas and diesel cars, according to research carried out by a advocacy group. This differs sharply with lab tests, which suggested a three-quarters decrease in pollution.

Researchers examined data from in-vehicle energy use meters of 800,000 cars registered in Europe from 2021 and 2023. The team found that real-world CO₂ output from PHEVs in 2023 were nearly five times higher than official estimates, increased from three and a half times in 2021.

“Actual emissions are increasing, while official emissions are decreasing,” stated a lead researcher involved in the study. “This gap is growing and poses a serious problem. Consequently, PHEVs emit nearly as heavily as gasoline cars.”

Primary Reasons Driving the Discrepancy

Analysts linked the majority of the difference to inflated estimates of the “electric driving share” – the percentage of kilometers travelled in battery mode compared to total distance. They determined that just 27% of driving was completed in EV mode, whereas lab estimates suggested 84%.

Even, when operating in electric mode, pollution amounts were significantly higher than official projections. That happened because EV motors were insufficiently powerful sufficient to operate independently, leading to engines using gasoline for almost a third of the travel completed in EV mode.

Policy and Financial Implications

According to estimates, the underestimation of PHEV CO2 output allowed four major carmaker companies to escape more than €5bn in penalties between 2021 and 2023, by artificially easing compliance with EU average fleet CO₂ targets.

Furthermore, owners of PHEVs could spend about €500 extra per year in running costs than is assumed under laboratory conditions.

“The bold statements that manufacturers often promote about their plug-in hybrid cars are clearly way off the mark,” stated a transport expert. “Buyers are being misled into believing that by buying a PHEV, they are benefiting the planet and cutting costs. Actually, PHEVs are only slightly improved than standard gas and diesel vehicles in terms of energy use, CO₂ emissions, and running expenses.”

Policy Discussion and Automotive Lobbying

Plug-in hybrid vehicles have lately been drawn again into policy discussions as carmakers have lobbied the EU to relax CO₂ targets. A proposed ban on new combustion engine vehicles in 2035 has faced intense lobbying from the car sector and resistance from EU countries with large automotive manufacturing.

Several high-level politicians have proposed PHEVs as a possible “flexibility” option to introduce in the regulation.

One independent energy economics expert, who was not involved with the research, described the analysis a “very useful contribution” after a long period in which segments of the automotive sector argued there was insufficient data to accurately assess real-world CO2 output.

“These findings show, without question, that the gap between lab and real-world PHEV energy use and CO₂ output is significantly larger than for petrol or conventional cars,” the expert said. “All regulatory changes concerning PHEVs should be made with utmost caution and considering that data.”