🔗 Share this article

PHEVs emit almost five times more global warming pollution than lab-reported data indicate, as per a new report.

Growing Gap In Lab and Actual Emissions

Statistics reveals that PHEVs emit just one-fifth lower CO₂ than traditional gas and diesel cars, according to analysis carried out by a advocacy group. That differs sharply with lab tests, which suggested a three-quarters reduction in pollution.

Analysts studied data from onboard energy use monitors of 800,000 vehicles sold in Europe from 2021 and 2023. They discovered that actual CO₂ emissions from PHEVs in 2023 were nearly five times higher than lab estimates, up from 3.5 times in 2021.

“Actual CO2 output are rising, while lab-reported figures are decreasing,” stated a lead analyst participating in the report. “This gap is widening and creates a significant issue. Consequently, PHEVs emit almost as much as petrol vehicles.”

Key Reasons Behind the Discrepancy

Analysts attributed most of the gap to inflated estimates of the “electric driving share” – the percentage of kilometers driven in electric power relative to overall mileage. The team found that just 27% of driving was done in electric mode, whereas lab estimates assumed 84%.

Additionally, when running in electric mode, emission amounts were well above lab estimates. That occurred because electric motors were insufficiently powerful sufficient to function alone, leading to engines burning gasoline for almost one-third of the distance covered in electric mode.

Policy and Economic Implications

According to estimates, the lowballing of PHEV CO2 output allowed several large carmaker companies to avoid more than €5bn in penalties between 2021 and 2023, by artificially simplifying compliance with EU average fleet CO₂ targets.

Additionally, drivers of PHEVs could pay about €500 extra per year in running expenses than would be assumed under laboratory conditions.

“The strong claims that manufacturers often promote about their PHEV vehicles are obviously way off the truth,” commented a transport expert. “Consumers are being misled into believing that by purchasing a PHEV, they are helping the environment and saving costs. In reality, PHEVs are little improved than regular petrol and diesel cars in terms of fuel use, CO₂ production, and running expenses.”

Policy Discussion and Automotive Lobbying

Plug-in hybrid vehicles have recently been brought again into political discussions as automakers have lobbied the EU to weaken CO₂ targets. A planned prohibition on sales of new combustion engine vehicles in 2035 has faced intense pressure from the automotive industry and opposition from member states with large automotive manufacturing.

Several senior officials have suggested plug-in hybrids as a possible “flexibility” option to include in the legislation.

An independent energy economics expert, who was unaffiliated with the research, called the analysis a “very useful addition” after years in which parts of the car sector claimed there was too little information to properly evaluate actual emissions.

“The results show, without question, that the gap between official and real-world PHEV fuel consumption and CO₂ output is significantly larger than for petrol or diesel vehicles,” the expert stated. “Any regulatory adjustments regarding PHEVs should be implemented with extreme caution and considering that data.”