🔗 Share this article

PHEVs release almost five times more global warming emissions than lab-reported figures indicate, as per a recent analysis.

Growing Gap Between Official and Actual Emissions

Data shows that PHEVs emit just 19% less CO₂ than traditional gas and diesel vehicles, based on analysis conducted by a advocacy group. This contrasts sharply with laboratory tests, which suggested a 75% reduction in emissions.

Analysts examined information from onboard fuel consumption monitors of eight hundred thousand vehicles registered in Europe from 2021 and 2023. The team 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.

“Real-world CO2 output are rising, while lab-reported emissions are decreasing,” said a senior researcher involved in the report. “This discrepancy is widening and poses a serious problem. As a result, PHEVs pollute almost as much as gasoline vehicles.”

Key Factors Behind the Emissions Gap

Analysts attributed most of the gap to inflated estimates of the “utility factor” – the ratio of kilometers driven in battery mode compared to overall distance. The team found that only 27% of travel was completed in electric mode, while official estimates suggested 84%.

Even, when operating in electric mode, pollution amounts were well above lab estimates. This occurred because EV motors were insufficiently powerful enough to function independently, leading to combustion motors burning gasoline for nearly a third of the travel completed in EV mode.

Policy and Economic Consequences

Based on calculations, the lowballing of PHEV CO2 output enabled four major carmaker groups to escape more than €5bn in fines between 2021 and 2023, by falsely simplifying adherence with European Union fleet-average CO₂ standards.

Furthermore, drivers of PHEVs would spend approximately €500 extra annually in operating costs than would be estimated under lab tests.

“The strong claims that manufacturers like to make about their plug-in hybrid cars are clearly far from the mark,” stated a automotive analyst. “Consumers are being duped into thinking that by purchasing a PHEV, they are helping the planet and cutting costs. Actually, PHEVs are only slightly improved than standard petrol and diesel cars in terms of energy consumption, CO₂ emissions, and running costs.”

Political Debate and Automotive Pressure

Hybrid cars have recently been brought back into policy discussions as automakers have pressed the European Union to relax CO₂ targets. A planned prohibition on new internal combustion cars in 2035 has faced intense lobbying from the car sector and opposition from EU countries with large car industries.

Several high-level officials have suggested PHEVs as a potential “flexibility” solution to introduce in the legislation.

One external energy policy specialist, who was not involved with the study, described the report a “very useful contribution” after years in which parts of the automotive industry argued there was insufficient information to accurately assess actual emissions.

“These findings demonstrate, beyond any doubt, that the gap between lab and real-world PHEV energy use and CO₂ output is much, much larger than for petrol or conventional cars,” the expert said. “All policy adjustments concerning PHEVs should be implemented with extreme care and considering this data.”