Plug-in Hybrid electric Cars Pollute Nearly as Much as Gasoline Cars, Report Finds
Plug-in hybrid electric vehicles emit almost 5x more planet-heating pollution than lab-reported data show, according to a recent report.
Widening Discrepancy Between Lab and Real-World Emissions
Statistics reveals that PHEVs release only one-fifth lower CO2 than traditional gas and diesel vehicles, based on analysis conducted by a non-profit group. This contrasts sharply with laboratory estimates, which assumed a three-quarters decrease in emissions.
Analysts studied information from onboard fuel consumption monitors of 800,000 vehicles registered in the EU from 2021 and 2023. The team found that actual CO2 emissions from PHEVs in 2023 were nearly five times higher than official estimates, increased from 3.5 times in 2021.
“Real-world CO2 output are rising, while lab-reported figures are decreasing,” stated a senior researcher involved in the study. “This gap is widening and poses a significant issue. As a result, PHEVs emit nearly as much as petrol cars.”
Primary Reasons Driving the Emissions Gap
Analysts linked most of the difference to inflated estimates of the “electric driving share” – the ratio of kilometers driven in battery power relative to overall mileage. The team found that just 27% of travel was completed in EV mode, whereas official estimates assumed over four-fifths.
Even, when operating in electric mode, emission levels were significantly higher than official estimates. This happened because EV motors were not strong enough to function alone, leading to combustion motors using gasoline for almost a third of the distance completed in electric mode.
Policy and Economic Consequences
Based on estimates, the underestimation of PHEV CO2 output enabled several large carmaker companies to escape over €5bn in penalties between 2021 and 2023, by falsely easing adherence with European Union fleet-average CO2 standards.
Additionally, drivers of PHEVs would spend about €500 more annually in running costs than is estimated under lab conditions.
“The bold claims that manufacturers often promote about their plug-in hybrid cars are clearly way off the truth,” commented a transport analyst. “Consumers are being duped into thinking that by buying a PHEV, they are benefiting the environment and saving money. Actually, PHEVs are little improved than regular petrol and diesel vehicles in terms of fuel consumption, CO2 production, and running expenses.”
Political Discussion and Automotive Lobbying
Plug-in hybrid cars have lately been drawn again into political debates as automakers have pressed the European Union to relax CO2 targets. A planned prohibition on new internal combustion vehicles in 2035 has faced heavy lobbying from the automotive sector and opposition from member states with significant automotive industries.
Several senior officials have suggested plug-in hybrids as a potential “compromise” option to include in the regulation.
One independent energy economics expert, who was unaffiliated with the study, called the analysis a “very useful contribution” after years in which segments of the car sector argued there was too little data to properly assess actual emissions.
“These findings demonstrate, without question, that the gap between official and real-world PHEV energy use and CO2 emissions is significantly greater than for gasoline or conventional cars,” the expert said. “All regulatory adjustments concerning PHEVs should be made with utmost care and considering that data.”
