🔗 Share this article

PHEVs release nearly 5x more planet-heating emissions than lab-reported data indicate, as per a new report.

Widening Discrepancy Between Official and Actual CO2 Output

Statistics reveals that PHEVs emit just one-fifth less CO₂ than conventional gas and diesel vehicles, according to research carried out by a non-profit 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. The team discovered that real-world CO₂ output from PHEVs in 2023 were 4.9 times higher than lab figures, up from three and a half times in 2021.

“Actual CO2 output are increasing, while lab-reported emissions are decreasing,” stated a lead researcher involved in the study. “That discrepancy is widening and creates a significant issue. Consequently, PHEVs emit almost as heavily as gasoline vehicles.”

Key Reasons Behind the Emissions Gap

Analysts linked the majority of the gap to overestimates of the “electric driving share” – the percentage of miles driven in battery power compared to overall distance. The team found that just 27% of driving was completed in EV mode, while official estimates assumed 84%.

Even, when operating in EV mode, emission amounts were significantly higher than lab estimates. That occurred because electric motors were not strong enough to function alone, leading to combustion motors using gasoline for nearly a third of the travel covered in EV mode.

Policy and Financial Implications

According to calculations, the underestimation of PHEV emissions enabled several major automaker groups to avoid more than €5bn in fines between 2021 and 2023, by artificially easing adherence with European Union fleet-average CO₂ standards.

Additionally, drivers of PHEVs could pay approximately €500 more annually in operating costs than is assumed under laboratory tests.

“The strong claims that manufacturers often promote about their PHEV cars are clearly far from the mark,” stated a automotive analyst. “Consumers are being duped into believing that by buying a PHEV, they are benefiting the planet and saving costs. In reality, PHEVs are only slightly improved than standard gas and diesel vehicles in terms of energy use, CO₂ production, and operating costs.”

Policy Discussion and Automotive Lobbying

Hybrid vehicles have lately been brought back into policy discussions as automakers have lobbied the European Union to relax CO₂ targets. A proposed prohibition on new internal combustion cars in 2035 has faced intense pressure from the car industry and resistance from member states with significant car manufacturing.

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

One external energy policy expert, who was unaffiliated with the research, described the analysis a “very useful addition” after a long period in which parts of the automotive industry argued there was insufficient data to properly evaluate real-world CO2 output.

“The results demonstrate, beyond any doubt, that the difference between lab and real-world PHEV fuel consumption and CO₂ output is much, much greater than for petrol or diesel vehicles,” the expert stated. “All regulatory adjustments regarding PHEVs should be implemented with extreme caution and in the light of that evidence.”