Plug in Hybrid electric Vehicles Pollute Almost as Much as Gasoline Vehicles, Report Reveals

Plug-in hybrid electric vehicles produce nearly five times greater global warming emissions than lab-reported data show, according to a new report.

Widening Gap Between Lab and Real-World CO2 Output

Statistics reveals that PHEVs release only one-fifth less CO₂ than conventional gas and diesel cars, based on analysis conducted by a non-profit group. This differs significantly with laboratory tests, which suggested a three-quarters reduction in pollution.

Researchers examined information from onboard fuel consumption monitors of 800,000 vehicles sold in Europe from 2021 and 2023. The team found that actual CO₂ output from PHEVs in 2023 were nearly five times higher than official figures, up from three and a half times in 2021.

“Real-world emissions are rising, while lab-reported figures are decreasing,” stated a lead researcher involved in the report. “That discrepancy is growing and creates a serious issue. Consequently, PHEVs emit almost as heavily as gasoline cars.”

Key Factors Driving the Discrepancy

Analysts linked most of the gap to overestimates of the “utility factor” – the percentage of miles travelled in battery mode relative to overall distance. The team determined that just a quarter of travel was completed in electric mode, whereas official estimates suggested over four-fifths.

Additionally, when operating in electric mode, emission levels were well above lab projections. That occurred because EV motors were not strong enough to operate alone, leading to engines burning fossil fuels for almost a third of the distance completed in electric mode.

Policy and Financial Implications

Based on estimates, the lowballing of PHEV CO2 output enabled several large automaker companies to avoid over €5bn in penalties between 2021 and 2023, by falsely simplifying adherence with European Union average fleet CO₂ targets.

Furthermore, owners of PHEVs could spend approximately €500 more annually in running expenses than is estimated under lab conditions.

“The strong statements that automakers like to make about their PHEV vehicles are obviously way off the mark,” commented a transport analyst. “Buyers are being duped into believing that by buying a PHEV, they are helping the environment and saving money. In reality, PHEVs are little better than regular petrol and diesel cars in terms of energy use, CO₂ production, and running expenses.”

Policy Debate and Industry Pressure

Plug-in hybrid vehicles have lately been brought again into political discussions as automakers have lobbied the European Union to weaken CO₂ standards. A planned ban on new combustion engine vehicles in 2035 has faced heavy lobbying from the automotive industry and resistance from EU countries with large automotive industries.

Several senior officials have proposed PHEVs as a potential “compromise” solution to introduce in the regulation.

One independent energy policy expert, who was unaffiliated with the study, called the analysis a “very useful addition” after years in which parts of the car industry argued there was too little information to accurately assess actual CO2 output.

“These findings demonstrate, without question, that the difference in lab and real-world PHEV energy use and CO₂ emissions is significantly greater than for gasoline or conventional vehicles,” they stated. “All regulatory changes concerning PHEVs should be implemented with utmost care and in the light of this data.”