PHEVs unable to achieve WLTP figures in real-world test

An environmental group has tested three plug-in hybrid (PHEV) vehicles and found that, in certain conditions, they emit more than the official WLTP figure.

Transport and Environment commissioned a study that measured the real-world tailpipe emissions of three models driving around a prescribed test route in Austria. The testing did not mirror the official WLTP procedure.

The vehicles were tested in hybrid mode, with an empty battery and for overall zero-emission range

When driven in hybrid mode, with a fully charged battery, the best-performing model emitted 20% more pollution than claimed in official testing. The test route was 34 miles and included sections of motorway and city driving.

Richard Hebditch, director of Transport & Environment UK, said: “Plug-in hybrids are sold to drivers and governments as part of the climate solution. The truth is they pollute far more than advertised and are a dangerous distraction from full electrification. In city and commuter tests, they pollute significantly more than advertised. The Government’s plans to decarbonise driving must be based on the reality of their emissions, not on the industry’s claims.”

The vehicles that were used in the test were the BMW 330e xDrive Touring, Peugeot 308 Hybrid 225 and the Renault Megane E-Tech.

The 308 delivered the best performance in relation to its official figures, when driven in Hybrid mode. Here it emitted 33g/km of CO2, compared to a WLTP figure of 27g/km.

The Renault completed the test having emitted 50g/km, compared to an official figure of 30g/km.

Both models used their entire battery charge during the test.

BMW’s 330e emitted 112g/km during the test. However, at the end of the drive it still had between 50% and 75% charge remaining. When the 3 Series was switched to its adaptive hybrid mode and re-tested, the CO2 figure fell to 66g/km and the car ended the test with 25% charge remaining. The official figure is 33g/km.

The Megane, which is no longer sold in the UK, delivered the best range performance with an achievement of 30.5 miles on a full charge. The 308 managed 25.6 miles and the BMW 20.8.

Separate testing by What Car? found that electric cars, on average, fall short of their WLTP-claimed range figure by 14.8%

In the charge sustaining test, where the vehicles were driven with an empty battery in hybrid mode, the Renault emitted 138g/km, the Peugeot emitted 197g/km and the BMW emitted 204g/km.

Transport and Environment concluded that PHEVs pollute “significantly more than advertised” on longer routes and believes the Government should tax PHEVs based on their actual pollution.

The organisation did not provide any comparative data for petrol, diesel or hybrid-powered cars.