🔗 Share this article

Plug-in hybrid cars emit almost 5x greater global warming emissions than lab-reported data show, as per a recent report.

Widening Gap In Lab and Actual CO2 Output

Data shows that PHEVs emit just one-fifth lower CO₂ than traditional gas and diesel vehicles, according to research conducted by a advocacy group. This contrasts significantly with lab tests, which assumed a three-quarters decrease in emissions.

Analysts studied information from in-vehicle fuel consumption monitors of eight hundred thousand cars registered in Europe from 2021 and 2023. They found that real-world CO₂ output from PHEVs in 2023 were nearly five times higher than lab estimates, increased from three and a half times in 2021.

“Actual emissions are rising, while official figures are decreasing,” stated a senior researcher involved in the study. “That gap is growing and creates a serious issue. As a result, PHEVs pollute almost as heavily as gasoline cars.”

Key Reasons Behind the Emissions Gap

Researchers attributed most of the difference to overestimates of the “utility factor” – the percentage of miles driven in battery mode relative to overall distance. They found that just 27% of driving was completed in electric mode, while official estimates suggested 84%.

Even, when operating in EV mode, emission amounts were well above official projections. That occurred because EV motors were not strong enough to function alone, resulting to combustion motors using fossil fuels for almost one-third of the distance covered in electric mode.

Policy and Financial Implications

According to calculations, the underestimation of PHEV emissions enabled several large automaker companies to escape over €5bn in penalties between 2021 and 2023, by falsely easing adherence with European Union average fleet CO₂ standards.

Furthermore, drivers of PHEVs could spend about €500 extra per year in running costs than is estimated under laboratory tests.

“The strong claims that automakers like to make about their PHEV vehicles are obviously far from the mark,” stated a transport expert. “Buyers are being duped into believing that by buying a PHEV, they are helping the environment and cutting money. Actually, PHEVs are only slightly improved than standard gas and diesel vehicles in terms of energy use, CO₂ production, and running costs.”

Political Debate and Industry Lobbying

Hybrid cars have recently been brought back into political debates as carmakers have pressed the EU to relax CO₂ targets. A proposed ban on sales of new combustion engine vehicles in 2035 has faced heavy lobbying from the car sector and resistance from member states with large car manufacturing.

Several senior officials have suggested PHEVs as a possible “flexibility” solution to introduce in the regulation.

One external energy policy expert, who was not involved with the research, called the report a “highly valuable addition” after years in which parts of the automotive sector argued there was insufficient information to properly evaluate real-world CO2 output.

“The results show, without question, that the difference in official and actual PHEV fuel consumption and CO₂ output is much, much greater than for petrol or conventional vehicles,” the expert stated. “All policy adjustments regarding PHEVs should be implemented with utmost caution and considering this data.”