🔗 Share this article

PHEVs emit nearly 5x greater planet-heating pollution than official figures indicate, according to a recent analysis.

Widening Discrepancy In Official and Real-World CO2 Output

Data shows that PHEVs release just one-fifth less CO₂ than conventional gas and diesel vehicles, according to analysis carried out by a advocacy organization. That differs significantly with lab estimates, which assumed a 75% reduction in pollution.

Analysts studied data from onboard energy use monitors of 800,000 cars sold in Europe from 2021 and 2023. The team found that real-world CO₂ emissions from PHEVs in 2023 were 4.9 times higher than official figures, increased from three and a half times in 2021.

“Real-world CO2 output are increasing, while lab-reported figures are falling,” said a senior researcher involved in the study. “That gap is widening and creates a significant issue. As a result, PHEVs pollute almost as heavily as petrol vehicles.”

Key Reasons Behind the Discrepancy

Researchers attributed most of the gap to inflated estimates of the “utility factor” – the ratio of miles travelled in battery power relative to total distance. They found that only 27% of travel was completed in EV mode, whereas lab assumptions suggested 84%.

Even, when operating in electric mode, pollution amounts were well above lab projections. This occurred because electric motors were insufficiently powerful enough to function alone, leading to engines using fossil fuels for almost a third of the distance completed in electric mode.

Regulatory and Financial Consequences

According to estimates, the lowballing of PHEV emissions enabled four large automaker groups to avoid more than €5bn in penalties from 2021 and 2023, by falsely easing adherence with European Union average fleet CO₂ standards.

Furthermore, drivers of PHEVs would spend approximately €500 more per year in operating costs than is estimated under laboratory tests.

“The bold claims that manufacturers often promote about their PHEV cars are obviously way off the mark,” stated a transport expert. “Consumers are being duped into believing that by buying a PHEV, they are benefiting the planet and cutting money. In reality, PHEVs are little better than standard petrol and diesel vehicles in terms of energy use, CO₂ emissions, and operating expenses.”

Political Debate and Industry Pressure

Hybrid vehicles have lately been drawn back into policy debates as automakers have pressed the EU to weaken CO₂ standards. A planned ban on sales of new combustion engine cars in 2035 has faced intense pressure from the automotive industry and resistance from EU countries with significant automotive industries.

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

An independent energy policy expert, who was unaffiliated with the research, called the report a “highly valuable contribution” after years in which segments of the car industry argued there was too little information to properly assess real-world CO2 output.

“These findings show, beyond any doubt, that the gap between official and actual PHEV energy use and CO₂ output is significantly greater than for gasoline or conventional vehicles,” they stated. “Any regulatory adjustments regarding PHEVs should be made with extreme caution and considering that evidence.”