Plug-in Hybrid Cars Emit Nearly as Heavily as Petrol Cars, Report Finds
Plug-in hybrid electric vehicles emit nearly five times greater planet-heating emissions than official data show, as per a new report.
Growing Discrepancy Between Lab and Actual CO2 Output
Statistics reveals that PHEVs emit just 19% less CO2 than traditional gas and diesel vehicles, according to analysis carried out by a non-profit group. This differs sharply with lab estimates, which assumed a 75% decrease in emissions.
Researchers studied information from in-vehicle fuel consumption monitors of 800,000 vehicles registered in Europe from 2021 and 2023. The team found that real-world CO2 emissions 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 figures are falling,” stated a senior researcher participating in the study. “This discrepancy is growing and creates a significant problem. As a result, PHEVs emit almost as heavily as petrol vehicles.”
Primary Factors Behind the Emissions Gap
Analysts linked most of the gap to overestimates of the “utility factor” – the percentage of miles travelled in electric power relative to overall mileage. The team found that just a quarter of travel was completed in electric mode, whereas official assumptions assumed over four-fifths.
Additionally, when operating in EV mode, emission amounts were significantly higher than official estimates. This happened because EV motors were not strong sufficient to operate alone, leading to combustion motors burning fossil fuels for almost one-third of the distance covered in electric mode.
Policy and Economic Consequences
Based on calculations, the underestimation of PHEV CO2 output enabled several large carmaker groups to escape over €5bn in fines from 2021 and 2023, by falsely easing compliance with EU fleet-average CO2 standards.
Additionally, drivers of PHEVs could spend about €500 more per year in operating costs than would be estimated under lab tests.
“The bold claims that manufacturers like to make about their plug-in hybrid cars are clearly way off the truth,” commented a automotive expert. “Consumers are being duped into thinking that by purchasing a PHEV, they are benefiting the planet and saving costs. Actually, PHEVs are only slightly improved than regular gas and diesel cars in terms of energy consumption, CO2 production, and operating costs.”
Policy Debate and Automotive Lobbying
Hybrid vehicles have lately been drawn again into policy debates as automakers have lobbied the EU to weaken CO2 targets. A planned ban on sales of new combustion engine cars in 2035 has faced heavy pressure from the automotive industry and opposition from EU countries with large automotive manufacturing.
Some high-level politicians have suggested PHEVs as a possible “compromise” solution to introduce in the legislation.
An independent energy economics specialist, who was not involved with the research, called the report a “very useful contribution” after years in which segments of the automotive industry argued there was insufficient information to properly assess real-world CO2 output.
“These findings demonstrate, beyond any doubt, that the gap between lab and real-world PHEV fuel consumption and CO2 output is significantly greater than for gasoline or diesel vehicles,” the expert stated. “Any regulatory changes concerning PHEVs should be implemented with extreme care and considering this evidence.”
