🔗 Share this article

Plug-in hybrid cars release almost five times more planet-heating emissions than official figures show, according to a recent report.

Widening Gap In Official and Real-World CO2 Output

Statistics reveals that PHEVs emit just one-fifth lower CO₂ than conventional gas and diesel vehicles, based on analysis carried out by a advocacy group. That differs sharply with laboratory tests, which suggested a 75% reduction in emissions.

Analysts studied information from onboard fuel consumption meters of eight hundred thousand vehicles registered in Europe between 2021 and 2023. They discovered that actual CO₂ emissions from PHEVs in 2023 were nearly five times higher than lab estimates, up from 3.5 times in 2021.

“Real-world emissions are increasing, while lab-reported emissions are decreasing,” stated a lead researcher involved in the study. “This discrepancy is growing and creates a serious issue. As a result, PHEVs emit nearly as much as petrol cars.”

Primary Reasons Driving the Discrepancy

Analysts linked the majority of the gap to inflated estimates of the “electric driving share” – the ratio of miles travelled in electric mode relative to total mileage. The team determined that only 27% of driving was done in electric mode, whereas official assumptions assumed 84%.

Additionally, when operating in electric mode, pollution levels were well above official projections. That occurred because EV motors were not strong sufficient to operate alone, resulting to combustion motors using gasoline for nearly a third of the distance covered in electric mode.

Policy and Financial Implications

Based on estimates, the underestimation of PHEV CO2 output enabled four large carmaker groups to avoid more than €5bn in penalties between 2021 and 2023, by falsely simplifying compliance with European Union average fleet CO₂ targets.

Furthermore, owners of PHEVs would spend about €500 extra annually in operating expenses than would be estimated under lab tests.

“The bold claims that automakers like to make about their plug-in hybrid vehicles are obviously way off the truth,” commented a automotive analyst. “Consumers are being duped into believing that by purchasing a PHEV, they are helping the environment and saving money. In reality, PHEVs are only slightly improved than standard gas and diesel vehicles in terms of energy consumption, CO₂ production, and operating expenses.”

Political Discussion and Automotive Pressure

Hybrid vehicles have recently been drawn again into political discussions as automakers have pressed the European Union to relax CO₂ targets. A proposed ban on sales of new combustion engine vehicles in 2035 has faced intense lobbying from the car sector and opposition from member states with large car manufacturing.

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

An external energy economics specialist, who was unaffiliated with the study, called the analysis a “highly valuable contribution” after years in which parts of the automotive sector claimed there was insufficient data to properly evaluate actual CO2 output.

“These findings show, without question, that the gap in lab and actual PHEV energy use and CO₂ output is much, much greater than for petrol or diesel vehicles,” the expert stated. “Any policy adjustments regarding PHEVs should be implemented with extreme caution and considering this data.”