Plug-in Hybrid electric Cars Pollute Almost as Much as Petrol Cars, Report Reveals

PHEVs emit nearly 5x more global warming pollution than lab-reported data show, as per a recent report.

Widening Gap In Official and Actual Emissions

Statistics reveals that PHEVs emit just one-fifth less CO₂ than traditional gas and diesel vehicles, based on research conducted by a non-profit group. This differs sharply with lab estimates, which assumed a three-quarters reduction in emissions.

Researchers examined information from onboard energy use monitors of 800,000 vehicles sold in the EU from 2021 and 2023. The team discovered that real-world CO₂ output from PHEVs in 2023 were 4.9 times higher than lab figures, increased from three and a half times in 2021.

“Actual CO2 output are increasing, while official emissions are falling,” stated a senior researcher participating in the study. “This discrepancy is widening and creates a significant issue. Consequently, PHEVs emit almost as much as gasoline cars.”

Key Factors Behind the Discrepancy

Researchers attributed the majority of the gap to inflated estimates of the “utility factor” – the percentage of miles driven in electric power relative to overall distance. They found that only a quarter of driving was done in EV mode, whereas official estimates assumed over four-fifths.

Additionally, when operating in electric mode, pollution amounts were well above official projections. This occurred because EV motors were insufficiently powerful enough to function alone, leading to engines burning gasoline for almost one-third of the distance completed in electric mode.

Regulatory and Economic Implications

Based on estimates, the underestimation of PHEV CO2 output enabled four large carmaker companies to avoid over €5bn in fines from 2021 and 2023, by artificially easing compliance with EU average fleet CO₂ targets.

Additionally, owners of PHEVs would spend about €500 more per year in operating costs than would be assumed under laboratory tests.

“The bold statements that manufacturers like to make about their plug-in hybrid vehicles are obviously far from the truth,” commented a automotive analyst. “Consumers are being duped into believing that by purchasing a PHEV, they are helping the environment and saving money. In reality, PHEVs are only slightly improved than regular petrol and diesel cars in terms of energy use, CO₂ emissions, and operating expenses.”

Policy Discussion and Industry Pressure

Plug-in hybrid cars have lately been drawn back into policy debates as automakers have pressed the EU to relax CO₂ targets. A proposed prohibition on new combustion engine vehicles in 2035 has faced intense lobbying from the car industry and resistance from member states with significant automotive industries.

Some high-level officials have suggested plug-in hybrids as a potential “compromise” option to include in the legislation.

An independent energy policy specialist, who was not involved with the research, called the report a “highly valuable addition” after a long period in which parts of the car sector argued there was too little data to accurately evaluate actual CO2 output.

“The results demonstrate, beyond any doubt, that the difference in lab and actual PHEV energy use and CO₂ output is significantly larger than for gasoline or diesel cars,” they stated. “Any policy changes regarding PHEVs should be implemented with utmost caution and considering this evidence.”