Plug-in Hybrids pollute more than advertised, new study

PHEVs should not be treated as zero-emission vehicles and that at the very least, the incentives should be based on real-world pollution.

A new study conducted by Graz University of Technology in collaboration with Brussels-based Transport & Environment (T&E) found that real-world data suggest that plug-in hybrids emit more pollutants than claimed.

Anna Krajinska, Vehicle Emissions Manager at Transport & Environment states that "PHEVs are sold as the perfect combination of battery and engine usage, however, real-world testing shows this to be a myth."

As part of the study, researchers at the university tested 3 new plug-in hybrid vehicles in real-world conditions in Graz, Austria: BMW 3-series, Peugeot 308 and Renault Megane. The results of the study showed that all three vehicles struggled to match their WLTP all-electric range estimates, while also emitting significantly higher pollutants than indicated.

With the batteries of the three PHEVs fully charged, researchers found that the Megane emitted 20% more CO2 than its claimed figure, the 308 emitted 70% more while the 3 Series' real-world emission was a massive 300% more than the WLTP estimates. In terms of its electric-only range, the Megane PHEV was the only one which matched its claimed range, with the 3 Series and the 308 achieving only 74% and 50% of its claimed zero-emissions range, respectively.

When the batteries were depleted, all three cars reportedly emitted between 5% - 7% more than what they are supposed to.

Krajinska stated that PHEVs should not be treated as zero-emission vehicles and that at the very least, the incentives should be based on real-world pollution. She went on to add that governments should end all purchase subsidies for PHEVs and instead encourage the use of battery electric cars.

Source: T&E Twitter