Plug-in Hybrid Vehicles Pollute Nearly as Much as Gasoline Cars, Study Reveals

PHEVs release almost five times greater planet-heating emissions than official figures show, according to a recent analysis.

Widening Gap In Lab and Actual CO2 Output

Statistics shows that PHEVs release just one-fifth lower CO₂ than traditional petrol and diesel vehicles, based on research carried out by a advocacy group. This contrasts significantly with laboratory tests, which assumed a 75% reduction in pollution.

Analysts studied data from in-vehicle fuel consumption meters of eight hundred thousand vehicles sold in the EU from 2021 and 2023. They discovered that real-world CO₂ emissions from PHEVs in 2023 were nearly five times higher than official figures, increased from three and a half times in 2021.

“Actual emissions are rising, while official emissions are decreasing,” stated a senior analyst participating in the study. “This gap is widening and creates a significant issue. As a result, PHEVs emit nearly as heavily as gasoline cars.”

Key Reasons Driving the Emissions Gap

Analysts attributed the majority of the difference to inflated estimates of the “utility factor” – the percentage of kilometers driven in battery power relative to total distance. They found that only a quarter of travel was completed in EV mode, while official estimates assumed over four-fifths.

Even, when operating in electric mode, pollution amounts were well above lab projections. That occurred because electric motors were insufficiently powerful enough to operate alone, leading to engines using fossil fuels for nearly a third of the distance completed in electric mode.

Regulatory and Financial Implications

According to calculations, the lowballing of PHEV CO2 output allowed several major automaker groups to avoid over €5bn in penalties from 2021 and 2023, by falsely simplifying adherence with European Union average fleet CO₂ standards.

Additionally, owners of PHEVs would spend about €500 extra per year in running expenses than would be estimated under laboratory conditions.

“The bold claims that automakers often promote about their plug-in hybrid cars are clearly way off the truth,” stated a automotive analyst. “Buyers are being misled into thinking that by buying a PHEV, they are benefiting the environment and cutting money. In reality, PHEVs are little better than standard gas and diesel vehicles in terms of fuel use, CO₂ emissions, and operating costs.”

Policy Discussion and Automotive Lobbying

Plug-in hybrid cars have recently been brought back into political discussions as carmakers have pressed the European Union to weaken CO₂ targets. A proposed ban on new combustion engine cars in 2035 has faced intense lobbying from the car industry and opposition from member states with significant automotive industries.

Some high-level politicians have suggested plug-in hybrids as a possible “flexibility” solution to include in the legislation.

An external energy policy expert, who was not involved with the research, described the report a “highly valuable addition” after years in which parts of the automotive sector claimed there was too little data to properly evaluate real-world CO2 output.

“The results show, beyond any doubt, that the difference in official and real-world PHEV energy use and CO₂ emissions is significantly larger than for petrol or conventional cars,” the expert said. “All regulatory changes concerning PHEVs should be implemented with extreme care and in the light of this evidence.”