Plug in Hybrid electric Vehicles Pollute Almost as Much as Petrol Cars, Study Reveals

Plug-in hybrid electric vehicles emit almost five times more global warming pollution than official figures indicate, as per a new report.

Growing Gap Between Official and Real-World CO2 Output

Statistics reveals that PHEVs release only one-fifth less CO₂ than traditional petrol and diesel cars, according to analysis conducted by a non-profit organization. That contrasts significantly with lab estimates, which suggested a 75% decrease in emissions.

Researchers examined information from in-vehicle energy use monitors of 800,000 cars sold in Europe from 2021 and 2023. The team found that real-world CO₂ emissions from PHEVs in 2023 were 4.9 times greater than official figures, up from 3.5 times in 2021.

“Actual CO2 output are increasing, while official figures are decreasing,” said a lead analyst involved in the study. “That gap is widening and poses a serious problem. Consequently, PHEVs emit nearly as much as petrol vehicles.”

Key Reasons Driving the Discrepancy

Analysts attributed most of the gap to overestimates of the “electric driving share” – the ratio of miles travelled in battery mode compared to overall distance. The team found that just 27% of driving was done in electric mode, while lab assumptions assumed over four-fifths.

Additionally, when operating in electric mode, pollution amounts were significantly higher than official projections. That happened because electric motors were insufficiently powerful enough to function alone, leading to engines using fossil fuels for nearly one-third of the distance completed in EV mode.

Regulatory and Financial Consequences

According to calculations, the lowballing of PHEV CO2 output allowed four major carmaker groups to avoid more than €5bn in penalties from 2021 and 2023, by falsely simplifying adherence with EU fleet-average CO₂ targets.

Additionally, owners of PHEVs could spend approximately €500 extra annually in operating expenses than would be estimated under lab tests.

“The bold claims that automakers often promote about their PHEV cars are obviously far from the mark,” stated a automotive expert. “Buyers are being duped into believing that by purchasing a PHEV, they are benefiting the planet and cutting money. Actually, PHEVs are little better than standard gas and diesel cars in terms of energy consumption, CO₂ emissions, and operating expenses.”

Political Discussion and Automotive Pressure

Hybrid cars have recently been drawn again into policy debates as automakers have pressed the EU to weaken CO₂ standards. A planned prohibition on sales of new internal combustion cars in 2035 has faced heavy pressure from the automotive sector and resistance from member states with significant automotive industries.

Several senior officials have proposed plug-in hybrids as a possible “compromise” solution to include in the legislation.

An independent energy economics specialist, who was unaffiliated with the study, described the report a “very useful contribution” after years in which parts of the automotive industry argued there was too little information to properly evaluate real-world emissions.

“These findings demonstrate, without question, that the difference between official and real-world PHEV energy use and CO₂ emissions is significantly greater than for gasoline or diesel cars,” they said. “Any regulatory adjustments regarding PHEVs should be made with utmost caution and in the light of this data.”