The study commissioned by Transport & Environment uses road tests to determine PHEV emissions
(sustainabilityenvironment.com) – PHEV pollute up to three times more on journeys between home and work than what car manufacturers claim. What is Phev? Plug-in Hybrid Electric Vehicle. But the emissions of plug-in hybrid cars can exceed even 5-7 times the official limits if the batteries are not fully charged. This is stated by an independent study that is based on road tests carried out with a BMW 3 Series, a Peugeot 308 and a Renault Megane.
The true emissions of plug-in hybrid cars
The emission values reported by the brands are around 27-36 g CO2/km. While those detected in the tests, when the battery is fully charged, reach 85-114 g CO2/km, reports the study carried out by the Technical University of Ganz and commissioned by the NGO Transport & Environment. With substantial differences between the three PHEV vehicles models.
Peugeot and Renault emitted 1.2-1.7 times the official CO2 (33-50 g CO2/km) in the test of a typical 55 km long, battery-powered commuter. Significantly better results than the BMW, which instead emitted 112 g CO2/km (3 times the official value). A measure, however, allows to halve emissions. “It was necessary to activate the “early” mode of BMW (programming the route in the satellite navigation system) to reduce the CO2 of commuters by about half, bringing it to 67 g CO2/km”, 2 times the official value, note T&E.
In the city the results are worse. Especially if the battery is not charged, the most common condition for urban use. In this configuration, emissions from plug-in hybrid cars reached 200 g CO2/km for BMW and Peugeot (as an SUV) and 138 for Renault. “Compared to the other two PHEV, the Renault has about half the engine power, a more powerful electric motor than the ICE and a lower weight, all important factors to limit CO2 emissions of plug-in hybrids,” notes the study.