Plug in Hybrid electric Vehicles Pollute Nearly as Much as Gasoline Cars, Study Reveals
PHEVs produce almost five times greater global warming pollution than official data indicate, according to a new analysis.
Growing Gap Between Official and Real-World Emissions
Statistics reveals that PHEVs emit only 19% less CO2 than conventional petrol and diesel vehicles, based on research conducted by a non-profit organization. This contrasts significantly with laboratory estimates, which assumed a 75% reduction in emissions.
Researchers studied information from onboard energy use meters of 800,000 vehicles registered in Europe between 2021 and 2023. The team found that real-world CO2 emissions from PHEVs in 2023 were nearly five times higher than lab figures, increased from three and a half times in 2021.
“Real-world emissions are rising, while lab-reported emissions are falling,” stated a senior analyst participating in the study. “This gap is widening and poses a serious issue. Consequently, PHEVs emit nearly as heavily as petrol cars.”
Key Factors Behind the Discrepancy
Analysts attributed most of the gap to inflated estimates of the “utility factor” – the ratio of miles travelled in electric power relative to overall mileage. They found that just a quarter of driving was completed in EV mode, whereas lab estimates suggested 84%.
Even, when operating in EV mode, pollution levels were significantly higher than official estimates. This occurred because EV motors were not strong sufficient to function independently, leading to engines burning gasoline for nearly a third of the travel completed in EV mode.
Regulatory and Financial Consequences
According to calculations, the underestimation of PHEV emissions enabled four major automaker groups to escape over €5bn in fines between 2021 and 2023, by artificially easing adherence with EU average fleet CO2 standards.
Furthermore, drivers of PHEVs would spend about €500 more per year in running costs than is assumed under lab tests.
“The strong statements that manufacturers like to make about their PHEV cars are obviously way off the mark,” commented a automotive expert. “Consumers are being duped into believing that by purchasing a PHEV, they are helping the planet and cutting costs. Actually, PHEVs are only slightly better than standard petrol and diesel vehicles in terms of energy use, CO2 emissions, and operating expenses.”
Political Debate and Automotive Pressure
Plug-in hybrid cars have lately been brought again into policy discussions as carmakers have lobbied the European Union to weaken CO2 targets. A proposed prohibition on sales of new combustion engine vehicles in 2035 has faced intense lobbying from the automotive industry and opposition from member states with large car industries.
Some high-level officials have proposed PHEVs as a possible “flexibility” solution to introduce in the legislation.
An external energy policy specialist, who was unaffiliated with the research, described the report a “highly valuable contribution” after a long period in which segments of the automotive sector argued there was too little data to properly evaluate actual emissions.
“The results demonstrate, without question, that the difference between lab and actual PHEV fuel consumption and CO2 emissions is much, much greater than for gasoline or conventional vehicles,” the expert stated. “All policy changes regarding PHEVs should be implemented with utmost caution and in the light of that data.”