Plug-in Hybrid electric Vehicles Emit Almost as Much as Gasoline Cars, Study Reveals
Plug-in hybrid cars release nearly five times more planet-heating emissions than official figures show, according to a new analysis.
Widening Gap In Lab and Actual Emissions
Statistics shows that PHEVs emit just one-fifth less CO2 than traditional petrol and diesel vehicles, based on research conducted by a advocacy organization. That contrasts sharply with laboratory tests, which suggested a three-quarters reduction in pollution.
Analysts studied information from in-vehicle fuel consumption monitors of eight hundred thousand vehicles sold in Europe between 2021 and 2023. They discovered that real-world CO2 output from PHEVs in 2023 were nearly five times higher than official estimates, increased from 3.5 times in 2021.
“Real-world emissions are rising, while official figures are decreasing,” said a senior analyst involved in the study. “That discrepancy is growing and creates a serious issue. As a result, PHEVs pollute nearly as much as gasoline vehicles.”
Key Reasons Driving the Discrepancy
Researchers linked most of the difference to overestimates of the “electric driving share” – the ratio of miles driven in battery power compared to overall distance. They determined that just a quarter of travel was done in electric mode, whereas official assumptions assumed 84%.
Even, when operating in EV mode, emission amounts were significantly higher than lab projections. That occurred because EV motors were not strong sufficient to function independently, resulting to engines using gasoline for almost one-third of the travel completed in electric mode.
Regulatory and Economic Consequences
Based on estimates, the underestimation of PHEV emissions allowed several major carmaker groups to escape more than €5bn in fines between 2021 and 2023, by falsely simplifying compliance with European Union fleet-average CO2 standards.
Furthermore, drivers of PHEVs could spend about €500 extra per year in running expenses than would be assumed under laboratory conditions.
“The strong statements that manufacturers often promote about their plug-in hybrid vehicles are clearly far from the truth,” commented a transport analyst. “Buyers are being duped into thinking that by purchasing a PHEV, they are helping the environment and saving costs. Actually, PHEVs are little better than regular petrol and diesel cars in terms of fuel consumption, CO2 emissions, and operating costs.”
Political Discussion and Automotive Lobbying
Plug-in hybrid vehicles have lately been drawn back into political discussions as carmakers have lobbied the EU to relax CO2 targets. A planned prohibition on sales of new internal combustion vehicles in 2035 has faced intense lobbying from the automotive industry and resistance from EU countries with significant automotive industries.
Some senior officials have proposed PHEVs as a potential “compromise” option to include in the regulation.
An external energy policy specialist, who was not involved with the research, called the report a “highly valuable addition” after a long period in which segments of the automotive industry claimed there was insufficient data to accurately evaluate actual emissions.
“The results show, without question, that the difference in official and real-world PHEV energy use and CO2 emissions is significantly larger than for gasoline or diesel cars,” they said. “All regulatory adjustments concerning PHEVs should be made with utmost caution and in the light of that evidence.”
