🔗 Share this article

Plug-in hybrid cars produce nearly 5x greater global warming emissions than official figures indicate, according to a recent report.

Growing Gap In Lab and Actual Emissions

Statistics reveals that PHEVs emit only 19% lower CO₂ than traditional gas and diesel vehicles, based on research carried out by a advocacy organization. That contrasts sharply with laboratory estimates, which assumed a three-quarters reduction in pollution.

Researchers studied information from onboard energy use monitors of eight hundred thousand vehicles registered in Europe between 2021 and 2023. They found that real-world CO₂ emissions from PHEVs in 2023 were 4.9 times greater than lab figures, increased from three and a half times in 2021.

“Real-world emissions are increasing, while lab-reported emissions are falling,” said a senior analyst involved in the report. “This discrepancy is growing and creates a serious problem. Consequently, PHEVs emit nearly as heavily as petrol vehicles.”

Key Factors Driving the Discrepancy

Researchers linked the majority of the difference to inflated estimates of the “utility factor” – the percentage of kilometers driven in electric mode compared to overall distance. The team found that only a quarter of driving was done in EV mode, while lab estimates suggested over four-fifths.

Even, when running in EV mode, pollution amounts were well above lab projections. This happened because EV motors were insufficiently powerful sufficient to operate independently, resulting to combustion motors using fossil fuels for nearly a third of the travel completed in electric mode.

Regulatory and Financial Consequences

Based on estimates, the lowballing of PHEV emissions allowed four major carmaker companies to escape over €5bn in fines from 2021 and 2023, by artificially easing adherence with European Union average fleet CO₂ standards.

Furthermore, owners of PHEVs could pay about €500 extra per year in operating costs than would be assumed under laboratory conditions.

“The strong statements that manufacturers like to make about their plug-in hybrid vehicles are obviously way off the mark,” commented a automotive expert. “Consumers are being duped into thinking that by purchasing a PHEV, they are benefiting the planet and cutting money. In reality, PHEVs are only slightly better than regular petrol and diesel vehicles in terms of energy use, CO₂ production, and operating costs.”

Policy Discussion and Industry Lobbying

Plug-in hybrid vehicles have recently been drawn back into political debates as carmakers have lobbied the European Union to relax CO₂ targets. A proposed prohibition on sales of new internal combustion vehicles in 2035 has faced heavy pressure from the automotive sector and resistance from EU countries with large car industries.

Some high-level officials have suggested plug-in hybrids as a possible “flexibility” solution to introduce in the regulation.

An independent energy policy expert, who was unaffiliated with the study, called the analysis a “very useful contribution” after years in which parts of the automotive sector claimed there was too little data to accurately assess real-world emissions.

“These findings demonstrate, without question, that the difference in lab and real-world PHEV energy use and CO₂ output is significantly larger than for petrol or diesel cars,” they stated. “All policy adjustments concerning PHEVs should be implemented with extreme caution and in the light of that data.”