Plug in Hybrid electric Cars Emit Almost as Much as Gasoline Cars, Report Reveals

Plug-in hybrid cars release nearly five times more global warming pollution than official figures show, according to a recent report.

Widening Discrepancy In Lab and Real-World CO2 Output

Statistics shows that PHEVs release only 19% lower CO₂ than conventional petrol and diesel vehicles, based on analysis carried out by a non-profit organization. This differs significantly with laboratory tests, which suggested a 75% reduction in emissions.

Analysts examined data from onboard fuel consumption monitors of 800,000 cars registered in Europe from 2021 and 2023. The team found that actual CO₂ output from PHEVs in 2023 were 4.9 times higher than official estimates, increased from 3.5 times in 2021.

“Real-world emissions are rising, while official figures are decreasing,” said a senior analyst participating in the report. “That gap is growing and creates a serious problem. As a result, PHEVs emit almost as heavily as petrol vehicles.”

Key Reasons Behind the Emissions Gap

Analysts linked most of the difference to inflated estimates of the “utility factor” – the ratio of kilometers travelled in battery mode relative to total mileage. The team determined that just 27% of driving was done in EV mode, whereas official estimates assumed over four-fifths.

Even, when operating in electric mode, emission levels were significantly higher than official projections. This happened because electric motors were insufficiently powerful enough to function alone, leading to engines using fossil fuels for almost one-third of the travel completed in electric mode.

Policy and Financial Consequences

According to calculations, the lowballing of PHEV CO2 output allowed several major carmaker companies to escape more than €5bn in fines between 2021 and 2023, by falsely easing adherence with European Union fleet-average CO₂ standards.

Furthermore, drivers of PHEVs could pay about €500 more per year in operating expenses than would be estimated under lab conditions.

“The strong statements that manufacturers like to make about their PHEV cars are clearly way off the truth,” commented a automotive expert. “Buyers are being duped into thinking that by buying a PHEV, they are benefiting the environment and cutting costs. In reality, PHEVs are only slightly better than standard gas and diesel cars in terms of fuel use, CO₂ emissions, and operating expenses.”

Political Debate and Automotive Lobbying

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

Some high-level politicians have suggested PHEVs as a potential “compromise” solution to include in the regulation.

One external energy policy specialist, who was not involved with the research, called the report a “highly valuable contribution” after a long period in which parts of the car industry argued there was too little data to properly evaluate actual CO2 output.

“The results demonstrate, without question, that the difference between lab and real-world PHEV fuel consumption and CO₂ output is much, much greater than for petrol or diesel vehicles,” they said. “All regulatory changes regarding PHEVs should be implemented with extreme caution and considering this evidence.”