Plug in Hybrid electric Cars Emit Nearly as Much as Gasoline Cars, Report Finds

PHEVs release almost five times greater planet-heating emissions than official data show, as per a new analysis.

Growing Gap Between Official and Actual CO2 Output

Data reveals that PHEVs release just 19% lower CO₂ than conventional petrol and diesel cars, based on analysis conducted by a advocacy organization. This differs sharply with laboratory tests, which suggested a three-quarters reduction in pollution.

Researchers studied data from onboard energy use monitors of eight hundred thousand cars registered in Europe from 2021 and 2023. They found that actual CO₂ output from PHEVs in 2023 were 4.9 times greater than official estimates, increased from three and a half times in 2021.

“Actual CO2 output are increasing, while official emissions are falling,” said a lead researcher participating in the report. “This discrepancy is growing and creates a serious problem. As a result, PHEVs pollute almost as heavily as gasoline cars.”

Key Factors Driving the Discrepancy

Analysts attributed the majority of the difference to inflated estimates of the “utility factor” – the percentage of kilometers driven in electric power compared to overall distance. They determined that just 27% of driving was done in EV mode, while lab assumptions assumed 84%.

Additionally, when running in electric mode, pollution amounts were well above official projections. This occurred because electric motors were not strong enough to function alone, resulting to engines burning fossil fuels for nearly a third of the distance covered in EV mode.

Policy and Economic Implications

According to estimates, the underestimation of PHEV emissions allowed four large carmaker companies to escape more than €5bn in fines between 2021 and 2023, by falsely easing compliance with EU fleet-average CO₂ targets.

Furthermore, drivers of PHEVs would spend approximately €500 extra annually in operating expenses than would be assumed under laboratory conditions.

“The bold statements that manufacturers like to make about their PHEV vehicles are clearly far from the mark,” commented a automotive expert. “Buyers are being misled into thinking that by purchasing a PHEV, they are helping the environment and saving costs. In reality, PHEVs are little improved than regular gas and diesel cars in terms of energy consumption, CO₂ production, and operating costs.”

Policy Debate and Industry Pressure

Hybrid cars have lately been drawn again into political debates as automakers have pressed the EU to weaken CO₂ standards. A planned prohibition on new combustion engine vehicles in 2035 has faced intense pressure from the car sector and resistance from member states with large automotive manufacturing.

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

An independent energy policy specialist, who was not involved with the research, called the analysis a “highly valuable contribution” after a long period in which segments of the car sector claimed there was insufficient information to accurately evaluate actual emissions.

“These findings show, beyond any doubt, that the difference between lab and real-world PHEV energy use and CO₂ output is much, much greater than for gasoline or conventional vehicles,” the expert stated. “All policy adjustments regarding PHEVs should be implemented with extreme care and considering that evidence.”