🔗 Share this article

Plug-in hybrid cars emit nearly 5x more planet-heating pollution than official figures show, according to a recent report.

Widening Gap In Official and Real-World CO2 Output

Statistics shows that PHEVs emit only 19% lower CO₂ than conventional gas and diesel vehicles, according to analysis carried out by a advocacy organization. That contrasts significantly with lab tests, which suggested a 75% reduction in pollution.

Analysts examined information from onboard fuel consumption monitors of eight hundred thousand vehicles sold in Europe between 2021 and 2023. The team found that actual CO₂ output from PHEVs in 2023 were nearly five times greater than lab estimates, increased from three and a half times in 2021.

“Real-world CO2 output are rising, while lab-reported figures are decreasing,” stated a senior analyst participating in the report. “This discrepancy is growing and creates a serious issue. Consequently, PHEVs pollute nearly as heavily as gasoline vehicles.”

Primary Reasons Behind the Discrepancy

Analysts attributed most of the difference to inflated estimates of the “utility factor” – the percentage of miles driven in electric mode relative to overall mileage. They found that only a quarter of driving was done in electric mode, while lab assumptions suggested over four-fifths.

Additionally, when running in EV mode, pollution levels were significantly higher than official estimates. That occurred because EV motors were not strong sufficient to function independently, leading to engines using gasoline for nearly one-third of the distance covered in EV mode.

Regulatory and Financial Implications

Based on calculations, the lowballing of PHEV emissions allowed several large carmaker companies to escape more than €5bn in penalties between 2021 and 2023, by artificially simplifying adherence with EU fleet-average CO₂ standards.

Additionally, owners of PHEVs could spend about €500 extra per year in operating expenses than would be assumed under lab conditions.

“The strong claims that automakers often promote about their plug-in hybrid vehicles are clearly way off the mark,” stated a automotive expert. “Consumers are being misled into thinking that by purchasing a PHEV, they are helping the planet and saving money. In reality, PHEVs are little improved than standard gas and diesel vehicles in terms of fuel use, CO₂ production, and running costs.”

Policy Discussion and Automotive Pressure

Hybrid cars have lately been brought again into policy discussions as carmakers have lobbied the European Union to weaken CO₂ targets. A planned ban on new combustion engine cars in 2035 has faced heavy lobbying from the automotive industry and resistance from member states with large car manufacturing.

Several senior politicians have proposed PHEVs as a possible “compromise” option to include in the regulation.

One external energy economics specialist, who was unaffiliated with the study, called the analysis a “highly valuable contribution” after a long period in which segments of the automotive industry claimed there was too little information to properly assess actual emissions.

“These findings demonstrate, without question, that the gap in official and real-world PHEV energy use and CO₂ emissions is significantly greater than for petrol or diesel vehicles,” the expert stated. “Any regulatory changes regarding PHEVs should be implemented with utmost caution and in the light of this data.”