🔗 Share this article

Plug-in hybrid cars produce nearly 5x greater global warming pollution than lab-reported figures indicate, as per a recent analysis.

Growing Discrepancy Between Lab and Actual Emissions

Statistics shows that PHEVs release just 19% lower CO₂ than traditional gas and diesel vehicles, based on analysis conducted by a advocacy organization. This differs significantly with laboratory estimates, which assumed a 75% decrease in pollution.

Researchers examined data from in-vehicle energy use meters of 800,000 vehicles registered in Europe between 2021 and 2023. The team found that actual CO₂ output from PHEVs in 2023 were 4.9 times greater than lab estimates, increased from 3.5 times in 2021.

“Real-world emissions are increasing, while lab-reported figures are falling,” stated a lead researcher involved in the study. “That discrepancy is widening and poses a significant problem. Consequently, PHEVs emit almost as much as petrol cars.”

Key Reasons Behind the Emissions Gap

Researchers linked most of the difference to inflated estimates of the “utility factor” – the ratio of kilometers driven in battery power relative to total mileage. They determined that only a quarter of driving was done in electric mode, whereas official assumptions suggested 84%.

Additionally, when running in EV mode, emission amounts were well above lab estimates. This occurred because electric motors were insufficiently powerful enough to function independently, resulting to combustion motors burning gasoline for almost a third of the travel covered in electric mode.

Policy and Financial Consequences

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

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

“The bold statements that automakers often promote about their PHEV vehicles are clearly far from the mark,” commented a automotive analyst. “Buyers are being duped into believing that by purchasing a PHEV, they are helping the planet and cutting costs. Actually, PHEVs are little better than standard gas and diesel vehicles in terms of energy use, CO₂ production, and running expenses.”

Political Discussion and Industry Pressure

Hybrid vehicles have lately been brought again into policy debates as automakers have lobbied the European Union to relax CO₂ standards. A planned prohibition on sales of new internal combustion vehicles in 2035 has faced heavy pressure from the car sector and resistance from member states with significant car manufacturing.

Some high-level officials have proposed PHEVs as a potential “compromise” solution to include in the legislation.

An independent energy economics specialist, who was unaffiliated with the study, described the analysis a “very useful addition” after a long period in which segments of the car sector claimed there was too little data to accurately evaluate real-world CO2 output.

“These findings demonstrate, without question, that the difference between official and actual PHEV fuel consumption and CO₂ emissions is significantly greater than for gasoline or diesel vehicles,” the expert said. “All regulatory adjustments concerning PHEVs should be made with extreme care and considering that data.”