Plug-in Hybrid electric Cars Pollute Nearly as Heavily as Petrol Vehicles, Report Finds

Plug-in hybrid electric vehicles produce almost 5x more global warming emissions than lab-reported figures indicate, as per a recent analysis.

Growing Discrepancy Between Lab and Real-World Emissions

Statistics shows that PHEVs emit just 19% lower CO₂ than traditional gas and diesel vehicles, according to research conducted by a advocacy group. This contrasts sharply with laboratory tests, which assumed a 75% reduction in pollution.

Researchers studied data from onboard energy use meters of eight hundred thousand vehicles registered in Europe between 2021 and 2023. They found that real-world CO₂ emissions from PHEVs in 2023 were nearly five times greater than official figures, up from 3.5 times in 2021.

“Actual emissions are increasing, while official emissions are falling,” stated a senior analyst participating in the report. “This gap is widening and creates a serious issue. Consequently, PHEVs pollute nearly as heavily as petrol cars.”

Primary Reasons Behind the Emissions Gap

Analysts attributed most of the difference to overestimates of the “utility factor” – the percentage of kilometers travelled in electric power relative to total mileage. They found that just 27% of driving was completed in EV mode, while official assumptions assumed over four-fifths.

Additionally, when operating in EV mode, emission amounts were significantly higher than lab projections. That happened because electric motors were not strong sufficient to function alone, leading to engines burning gasoline for almost one-third of the travel completed in electric mode.

Policy and Financial Implications

Based on estimates, the underestimation of PHEV emissions allowed several large automaker companies to avoid more than €5bn in fines from 2021 and 2023, by artificially simplifying compliance with EU average fleet CO₂ targets.

Additionally, drivers of PHEVs could pay approximately €500 extra annually in running expenses than would be estimated under laboratory conditions.

“The bold claims that automakers like to make about their PHEV vehicles are clearly way off the mark,” commented a transport analyst. “Buyers are being duped into thinking that by buying a PHEV, they are benefiting the environment and cutting costs. Actually, PHEVs are little improved than regular gas and diesel cars in terms of energy use, CO₂ production, and running expenses.”

Policy Debate and Automotive Pressure

Plug-in hybrid cars have lately been brought again into political debates as automakers have lobbied the EU to weaken CO₂ standards. A planned prohibition on new internal combustion cars in 2035 has faced intense pressure from the car sector and opposition from EU countries with large automotive manufacturing.

Some high-level officials have suggested PHEVs as a possible “flexibility” solution to introduce in the legislation.

One independent energy policy specialist, who was unaffiliated with the research, described the analysis a “very useful addition” after years in which parts of the car industry claimed there was insufficient data to accurately evaluate actual emissions.

“These findings demonstrate, without question, that the gap in lab and actual PHEV energy use and CO₂ emissions is much, much greater than for petrol or conventional vehicles,” they said. “All policy changes concerning PHEVs should be implemented with extreme caution and considering this data.”