Major plug-in hybrid cars pollute more than official measures suggest

BMW, Renault and Peugeot PHEVs all exceeded carbon dioxide output claimed in standard lab tests, on-road tests show

Popular plug-in hybrid cars emit significantly more carbon dioxide than official measures suggest, according to new on-road tests by academics that add to concerns over the true impact of cars sold as better for the environment.

Cars from BMW, Renault and Peugeot all emitted much more than standard lab tests had claimed, with the BMW 3 Series in particular emitting more than three times advertised, according to the research by Switzerland’s Graz University of Technology.