Plug-in Hybrid Cars Emit Nearly as Much as Gasoline Cars, Study Reveals
Plug-in hybrid cars produce nearly 5x more planet-heating emissions than official figures show, according to a new analysis.
Growing Discrepancy Between Official and Actual CO2 Output
Statistics reveals that PHEVs release only one-fifth less CO2 than conventional petrol and diesel cars, based on research conducted by a advocacy organization. This contrasts sharply with laboratory tests, which suggested a 75% decrease in pollution.
Analysts examined information from in-vehicle fuel consumption meters of eight hundred thousand vehicles registered in Europe between 2021 and 2023. The team found that real-world CO2 output from PHEVs in 2023 were 4.9 times higher than official figures, increased from three and a half times in 2021.
“Actual emissions are increasing, while official emissions are falling,” stated a senior researcher involved in the study. “This discrepancy is growing and creates a significant issue. As a result, PHEVs emit almost as heavily as gasoline cars.”
Key Reasons Behind the Discrepancy
Analysts attributed most of the difference to inflated estimates of the “utility factor” – the ratio of kilometers travelled in electric power compared to overall distance. They determined that just 27% of travel was done in electric mode, whereas lab assumptions suggested over four-fifths.
Additionally, when operating in electric mode, pollution levels were well above official estimates. This happened because EV motors were not strong enough to operate alone, resulting to engines burning fossil fuels for almost a third of the distance completed in EV mode.
Regulatory and Financial Consequences
According to estimates, the underestimation of PHEV emissions enabled several major carmaker groups to escape over €5bn in penalties from 2021 and 2023, by falsely easing compliance with EU average fleet CO2 targets.
Furthermore, drivers of PHEVs could pay about €500 more per year in running expenses than is assumed under laboratory tests.
“The bold claims that automakers like to make about their PHEV vehicles are clearly way off the mark,” stated a automotive analyst. “Consumers are being duped into thinking that by purchasing a PHEV, they are benefiting the environment and saving costs. In reality, PHEVs are only slightly better than standard gas and diesel vehicles in terms of energy use, CO2 emissions, and operating expenses.”
Political Debate and Industry Lobbying
Plug-in hybrid cars have recently been brought back into policy discussions as automakers have lobbied the EU to relax CO2 targets. A planned ban on sales of new internal combustion cars in 2035 has faced heavy lobbying from the automotive industry and resistance from member states with significant automotive manufacturing.
Several high-level officials have proposed PHEVs as a possible “compromise” solution to include in the regulation.
One external energy policy specialist, who was not involved with the research, called the analysis a “highly valuable addition” after a long period in which segments of the automotive sector argued there was insufficient data to accurately evaluate actual CO2 output.
“The results demonstrate, beyond any doubt, that the gap between lab and actual PHEV energy use and CO2 emissions is significantly larger than for petrol or diesel vehicles,” they said. “All regulatory changes regarding PHEVs should be made with utmost care and in the light of that data.”
