🔗 Share this article

Plug-in hybrid electric vehicles release almost five times greater global warming pollution than lab-reported figures indicate, as per a recent analysis.

Growing Discrepancy Between Official and Real-World Emissions

Statistics reveals that PHEVs emit only one-fifth less CO₂ than traditional gas and diesel cars, according to analysis carried out by a advocacy organization. That differs sharply with lab estimates, which suggested a 75% decrease in emissions.

Analysts examined information from onboard energy use meters of 800,000 vehicles sold in Europe from 2021 and 2023. The team found that actual CO₂ emissions from PHEVs in 2023 were nearly five times greater than lab estimates, increased from three and a half times in 2021.

“Real-world emissions are rising, while lab-reported emissions are decreasing,” said a senior analyst participating in the report. “That gap is growing and poses a significant problem. Consequently, PHEVs pollute nearly as much as petrol vehicles.”

Key Reasons Behind the Emissions Gap

Researchers linked the majority of the difference to inflated estimates of the “electric driving share” – the ratio of miles driven in battery mode compared to total distance. They determined that just 27% of driving was done in EV mode, whereas official estimates suggested 84%.

Even, when running in electric mode, emission amounts were significantly higher than official estimates. This occurred because electric motors were insufficiently powerful enough to function independently, leading to combustion motors using fossil fuels for nearly one-third of the travel completed in electric mode.

Regulatory and Economic Consequences

According to calculations, the underestimation of PHEV emissions enabled four major automaker companies to avoid over €5bn in penalties from 2021 and 2023, by falsely simplifying compliance with European Union fleet-average CO₂ targets.

Furthermore, drivers of PHEVs would pay approximately €500 extra annually in operating expenses than is assumed under laboratory conditions.

“The bold claims that automakers like to make about their plug-in hybrid cars are clearly way off the mark,” stated a automotive analyst. “Buyers are being duped into thinking that by buying a PHEV, they are helping the environment and saving money. In reality, PHEVs are only slightly improved than regular petrol and diesel cars in terms of energy consumption, CO₂ emissions, and operating costs.”

Political Discussion and Automotive Pressure

Plug-in hybrid vehicles have recently been drawn again into political discussions as carmakers have lobbied the European Union to weaken CO₂ standards. A proposed prohibition on sales of new internal combustion vehicles in 2035 has faced heavy pressure from the automotive sector and opposition from member states with significant car industries.

Several senior officials have suggested plug-in hybrids as a potential “flexibility” option to include in the legislation.

An independent energy policy specialist, who was unaffiliated with the study, described the report a “very useful addition” after years in which parts of the automotive industry argued there was too little information to properly assess real-world CO2 output.

“The results show, beyond any doubt, that the difference in lab and actual PHEV fuel consumption and CO₂ output is significantly greater than for gasoline or diesel vehicles,” they stated. “All policy adjustments concerning PHEVs should be made with extreme caution and considering this evidence.”