🔗 Share this article

PHEVs emit almost five times more planet-heating emissions than lab-reported figures show, as per a recent analysis.

Widening Gap Between Official and Real-World CO2 Output

Data reveals that PHEVs release only one-fifth less CO₂ than traditional petrol and diesel vehicles, based on analysis carried out by a advocacy group. This differs significantly with lab tests, which suggested a 75% decrease in emissions.

Analysts studied information from in-vehicle fuel consumption meters of eight hundred thousand vehicles sold in Europe between 2021 and 2023. The team found that real-world CO₂ emissions from PHEVs in 2023 were nearly five times greater than official estimates, increased from three and a half times in 2021.

“Real-world emissions are rising, while lab-reported emissions are decreasing,” stated a senior analyst participating in the report. “That discrepancy is widening and creates a serious problem. As a result, PHEVs pollute nearly as much as gasoline cars.”

Primary Reasons Behind the Emissions Gap

Researchers attributed most of the difference to inflated estimates of the “electric driving share” – the percentage of kilometers travelled in battery power relative to overall mileage. They found that just a quarter of driving was completed in EV mode, whereas lab assumptions assumed 84%.

Additionally, when operating in electric mode, emission levels were well above official projections. That occurred because electric motors were not strong sufficient to operate alone, leading to engines burning fossil fuels for almost a third of the travel completed in EV mode.

Regulatory and Economic Consequences

Based on estimates, the underestimation of PHEV CO2 output allowed four major carmaker companies to avoid more than €5bn in penalties between 2021 and 2023, by falsely easing compliance with EU fleet-average CO₂ targets.

Furthermore, drivers of PHEVs could pay approximately €500 extra annually in operating costs than would be estimated under laboratory conditions.

“The strong statements that automakers like to make about their PHEV cars are clearly far from the mark,” commented a automotive expert. “Buyers are being duped into thinking that by purchasing a PHEV, they are helping the planet and saving costs. Actually, PHEVs are only slightly improved than regular gas and diesel vehicles in terms of fuel consumption, CO₂ emissions, and running expenses.”

Political Discussion and Automotive Pressure

Plug-in hybrid vehicles have recently been drawn back into policy discussions as carmakers have pressed the European Union to weaken CO₂ standards. A proposed prohibition on new combustion engine vehicles in 2035 has faced intense pressure from the automotive industry and opposition from member states with large automotive manufacturing.

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

One external energy economics specialist, who was unaffiliated with the research, called the report a “very useful contribution” after years in which parts of the car sector argued there was insufficient data to accurately assess actual CO2 output.

“These findings demonstrate, beyond any doubt, that the difference in lab and actual PHEV energy use and CO₂ output is much, much greater than for petrol or diesel cars,” they stated. “All regulatory adjustments regarding PHEVs should be made with extreme care and in the light of that data.”