Impact of real-world driving on emissions from UK cars
Passenger cars and vans contribute to 17% of the UK’s total CO2 emissions and have an important role in meeting future targets. Despite rapid falls in the official emissions of new cars sold in the UK, evidence of a growing ‘gap’ between official and real-world driving CO2 emissions has received attention, and Government has become increasingly aware of the risks. The Committee on Climate Change commissioned Element Energy and the International Council on Clean Transportation (ICCT) to understand in detail the specific contributions to the emissions gap for the UK car and van fleet.
The authors of the study conclude:
• While the Worldwide harmonized Light vehicles Test Procedures (WLTP) will provide improvement in the real world emissions, a further move towards independent in-use conformity and on-road testing will be needed to close the gap.
• The CO2 emission data that will be recorded as part of the air pollution approach, could be published and made available for analysis of the on-road CO2 emissions of new vehicle types.
• Given the time required to introduce an improved testing scheme it is likely that the WLTP will be used to underpin future fleet emission targets. If this is the case, regulators will need to take into account the real-world emissions gap.
• Future CO2 targets defined using WLTP should be highly ambitious, ensuring genuine real-world emission reductions.
The introduction of the WLTP as currently planned in 2017.
