Question to the Department for Transport:

To ask Her Majesty's Government what assessment they have made of the finding in the report by Transport and Environment Plug-in hybrids: Is Europe heading for a new dieselgate?, published on 22 November, that emissions from plug-in hybrid vehicles are higher in road tests than those reported by manufacturers in laboratory tests.

The Government is confident in the robustness of the regulatory emissions test procedures for plug-in hybrids. However, we acknowledge that real-world emissions of plug-in hybrids can vary according to usage profiles and the findings of the report by Transport and Environment are being carefully considered.

The Department for Transport’s Market Surveillance Unit conducts its own impartial testing of vehicle emissions, including of plug-in hybrid vehicles in real-world conditions, and analysis of these results will inform our view of whether any future improvements to regulatory emissions tests are required.