🔗 Share this article

Plug-in hybrid electric vehicles produce almost 5x greater global warming emissions than lab-reported data show, as per a new analysis.

Growing Gap In Official and Actual CO2 Output

Statistics shows that PHEVs emit only one-fifth lower CO₂ than conventional gas and diesel vehicles, based on research carried out by a advocacy group. This contrasts significantly with laboratory tests, which assumed a three-quarters reduction in emissions.

Analysts studied information from in-vehicle fuel consumption monitors of 800,000 vehicles registered in Europe between 2021 and 2023. The team discovered that real-world CO₂ output from PHEVs in 2023 were 4.9 times greater than lab estimates, increased from 3.5 times in 2021.

“Actual CO2 output are increasing, while official figures are falling,” stated a lead researcher participating in the report. “This gap is widening and creates a serious issue. As a result, PHEVs emit almost as much as gasoline vehicles.”

Key Reasons Driving the Emissions Gap

Analysts attributed the majority of the difference to overestimates of the “utility factor” – the percentage of miles driven in electric mode compared to total distance. The team determined that just a quarter of driving was completed in electric mode, while official assumptions assumed over four-fifths.

Even, when running in EV mode, pollution amounts were significantly higher than official estimates. That occurred because electric motors were insufficiently powerful sufficient to operate alone, resulting to combustion motors using gasoline for almost one-third of the travel completed in electric mode.

Policy and Economic Implications

Based on calculations, the underestimation of PHEV emissions allowed four large carmaker companies to avoid more than €5bn in fines between 2021 and 2023, by artificially simplifying compliance with EU fleet-average CO₂ targets.

Furthermore, owners of PHEVs would pay about €500 extra annually in operating expenses than is assumed under laboratory tests.

“The strong claims that manufacturers like to make about their plug-in hybrid vehicles are clearly way off the truth,” commented a automotive expert. “Buyers are being misled into thinking that by buying a PHEV, they are benefiting the planet and cutting money. Actually, PHEVs are only slightly improved than standard gas and diesel cars in terms of energy use, CO₂ production, and operating expenses.”

Policy Discussion and Industry Pressure

Plug-in hybrid vehicles have lately been drawn again into policy discussions as automakers have pressed the European Union to weaken CO₂ standards. A proposed prohibition on new internal combustion cars in 2035 has faced intense lobbying from the automotive industry and resistance from EU countries with large automotive industries.

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

An external energy policy expert, who was unaffiliated with the study, called the analysis a “very useful contribution” after years in which parts of the automotive industry claimed there was insufficient information to properly evaluate real-world emissions.

“These findings show, beyond any doubt, that the gap in official and real-world PHEV energy use and CO₂ emissions is much, much greater than for gasoline or diesel vehicles,” they said. “All policy adjustments concerning PHEVs should be implemented with utmost caution and considering this data.”