Plug in Hybrid Vehicles Pollute Almost as Heavily as Gasoline Vehicles, Study Finds
Plug-in hybrid electric vehicles emit almost 5x more planet-heating emissions than official figures show, according to a new report.
Widening Gap Between Official and Actual Emissions
Statistics reveals that PHEVs release just one-fifth lower CO2 than traditional gas and diesel vehicles, according to research carried out by a advocacy group. This contrasts significantly with lab tests, which suggested a 75% reduction in emissions.
Researchers examined data from onboard fuel consumption monitors of 800,000 cars sold in Europe between 2021 and 2023. They found that real-world CO2 output from PHEVs in 2023 were nearly five times greater than lab estimates, increased from three and a half times in 2021.
“Actual emissions are rising, while official emissions are falling,” said a lead researcher participating in the study. “This gap is widening and creates a serious issue. As a result, PHEVs pollute almost as heavily as gasoline vehicles.”
Key Factors Driving the Discrepancy
Researchers attributed the majority of the difference to overestimates of the “electric driving share” – the percentage of kilometers travelled in battery mode relative to total mileage. The team determined that just a quarter of driving was done in EV mode, whereas official estimates assumed 84%.
Additionally, when running in electric mode, emission amounts were significantly higher than lab estimates. That happened because electric motors were not strong enough to function independently, resulting to engines burning gasoline for almost one-third of the travel covered in electric mode.
Regulatory and Financial Implications
Based on estimates, the underestimation of PHEV emissions allowed several major carmaker companies to escape over €5bn in penalties from 2021 and 2023, by artificially simplifying compliance with EU fleet-average CO2 standards.
Furthermore, owners of PHEVs could pay about €500 more per year in operating expenses than is assumed under lab tests.
“The strong statements that manufacturers like to make about their PHEV vehicles are clearly far from the truth,” commented a automotive expert. “Consumers are being misled into believing that by buying a PHEV, they are benefiting the environment and saving money. Actually, PHEVs are little improved than standard gas and diesel vehicles in terms of energy consumption, CO2 production, and running expenses.”
Political Discussion and Automotive Pressure
Plug-in hybrid cars have lately been brought again into political discussions as carmakers have pressed the EU to relax CO2 targets. A planned ban on sales of new internal combustion cars in 2035 has faced heavy pressure from the automotive industry and opposition from EU countries with large car industries.
Some senior politicians have proposed PHEVs as a potential “compromise” option to include in the regulation.
An independent energy economics specialist, who was unaffiliated with the study, called the report a “very useful contribution” after a long period in which parts of the car sector argued there was too little information to accurately evaluate actual emissions.
“The results demonstrate, beyond any doubt, that the gap in official and actual PHEV fuel consumption and CO2 emissions is significantly greater than for gasoline or conventional cars,” they stated. “Any policy adjustments regarding PHEVs should be implemented with extreme caution and in the light of that data.”
