Study shows plug-in hybrids polluting far more than expected

The study comes as certain automakers want to see plug-in hybrids continue to be included in the EU's strategy to decarbonize the auto sector.(AFP) — Plug-in hybrids have enjoyed a surge in popularity, but a study published Thursday showed they are polluting far more than most buyers think, as they run on batteries less than regulators expected.The study by the International Council on Clean Transportation, an environmental research group, looked at data from the onboard monitors of roughly 920,000 plug-in hybrids registered between 2021 and 2023.It found a “substantial and fast-growing gap between real-world and type-approval CO2 emissions for PHEVs registered in 2021–2023.”The type-approval norms include an assumption by regulators about the pollution the vehicles would emit based on the distances they would be driving using the battery and the distances using internal combustion engines.But the study found that average carbon dioxide emissions in real-world driving were 3.5 times higher than the 2021 type-approval values and 4.6 times higher than the 2023 type-approval values.The growing difference was due to an assumption that bigger batteries would lead to increased driving on battery power, but the real-world use data did not bear this out.The divergence “misleads consumers about expected energy costs” with plug-in hybrids, the ICCT said, as well as unduly opening them up to incentive schemes and skewing the determination whether automakers are complying with emissions rules.The ICCT, which was behind the 2015 revelations about diesel emissions that became known as the “Dieselgate” scandal, urged the EU to not delay a planned 2027 update to the calculations that would reduce the discrepancy with real-world emissions.It also called on the European Union to use real-world data to guide further updates.The publication of the study comes as certain automakers, particularly German carmakers, want to see plug-in hybrids continue to be included in the EU’s strategy to decarbonize the auto sector.Pushed by Germany, the EU last December abandoned its plans to ban the registration of new internal combustion engine vehicles in 2035.Instead, carmakers are supposed to reduce carbon dioxide levels by 90% from 2021 levels and compensate for the remaining 10%.However, Germany and its allies want the rules loosened further to make more room for hybrid vehicles, according to news reports.Subscribe to our free newslettersOur weekly newsletter Closing Arguments offers the latest about ongoing trials, major litigation and rulings in courthouses around the U.S. and the world, while the monthly Under the Lights dishes the legal dirt from Hollywood, sports, Big Tech and the arts.Additional Reads