🔗 Share this article

Plug-in hybrid cars emit almost 5x greater global warming emissions than official data indicate, according to a new report.

Growing Discrepancy Between Official and Actual CO2 Output

Data reveals that PHEVs release just one-fifth lower CO₂ than traditional petrol and diesel cars, according to research carried out by a non-profit organization. This contrasts sharply with laboratory estimates, which assumed a 75% decrease in pollution.

Analysts studied information from onboard fuel consumption monitors of 800,000 cars registered in Europe from 2021 and 2023. The team found that real-world CO₂ output from PHEVs in 2023 were nearly five times greater than official estimates, up from three and a half times in 2021.

“Real-world CO2 output are increasing, while official figures are falling,” stated a lead researcher involved in the report. “This gap is widening and creates a significant issue. Consequently, PHEVs pollute almost as heavily as petrol cars.”

Key Reasons Behind the Discrepancy

Researchers linked the majority of the gap to overestimates of the “utility factor” – the percentage of kilometers travelled in battery power relative to overall mileage. The team found that just 27% of travel was done in electric mode, whereas official assumptions assumed 84%.

Additionally, when operating in electric mode, emission levels were significantly higher than official projections. This happened because electric motors were insufficiently powerful enough to function independently, leading to engines burning fossil fuels for almost a third of the distance completed in EV mode.

Regulatory and Economic Consequences

According to estimates, the lowballing of PHEV emissions allowed four major automaker companies to escape more than €5bn in penalties between 2021 and 2023, by falsely easing adherence with European Union average fleet CO₂ targets.

Additionally, drivers of PHEVs would spend approximately €500 more per year in operating costs than would be assumed under lab tests.

“The strong claims that automakers often promote about their PHEV vehicles are obviously way off the truth,” commented a automotive expert. “Consumers are being misled into thinking that by buying a PHEV, they are benefiting the environment and saving money. In reality, PHEVs are little better than standard petrol and diesel vehicles in terms of energy consumption, CO₂ emissions, and operating costs.”

Policy Debate and Automotive Lobbying

Hybrid cars have lately been drawn back into political discussions as carmakers have lobbied the EU to relax CO₂ targets. A proposed prohibition on new combustion engine cars in 2035 has faced intense lobbying from the car sector and resistance from EU countries with large automotive industries.

Some senior politicians have proposed plug-in hybrids as a possible “compromise” solution to include in the regulation.

An external energy economics specialist, who was not involved with the study, described the analysis a “very useful contribution” after a long period in which parts of the automotive industry claimed there was insufficient data to accurately evaluate actual emissions.

“The results demonstrate, without question, that the gap in official and real-world PHEV fuel consumption and CO₂ output is much, much greater than for gasoline or conventional cars,” the expert said. “All policy changes regarding PHEVs should be made with extreme caution and considering this evidence.”