April 4, 2018

Vehicle Emissions Testing | What is CO2MPAS?

CO2MPAS To Plug The Gap Between NEDC And WLTP

The New European Drive Cycle (NEDC) test procedure for fuel consumption and emissions was replaced by The World Harmonised Light Vehicle Test Procedure (WLTP) in September 2017. The aim of the new test is to provide results that are far closer to those that would be achieved by drivers in real-world conditions.

All newly launched or updated cars have been tested under WLTP since September 2017 and all models will need to be tested under this new regime from September 2018. This means motor manufacturers are currently very busy attempting to get every vehicle through the new test before the autumn deadline.

However, HMRC has confirmed that for tax calculation purposes, NEDC CO2 figures will continue to be used until April 2020. This means a cross-over period where both sets of figures are required but only WLTP will be being measured.

co2 emissions increase as diesel sales deline

What is CO2MPAS?

CO2MPAS is a model developed by the European Commission that aims to give a vehicle tested under WLTP comparable CO2 values to those that would have been measured under NEDC.

For vehicles that are being tested under NEDC for the time being there is no impact. But for drivers selecting a company vehicle that is already being tested under WLTP, their benefit-in-kind tax will be calculated using the CO2MPAS conversion figure.

Vehicle Excise Duty (VED) and Class 1A National Insurance Contributions (NIC), which are both based on CO2 emissions, will be similarly impacted.

Will this cause any issues?

A number of bodies, including the Society of Motor Manufacturers and Traders (SMMT), have raised concerns that the WLTP CO2MPAS converted figures tend to be considerably higher those measured under NEDC.

This is borne out when looking at the new CO2 ratings of vehicles that have recently undergone a model upgrade and have therefore been tested under both NEDC and WLTP models. In some cases, the CO2MPAS converted WLTP figures see a double-digit percentage increase in the measured amount of CO2 produced when compared to that measured under NEDC.

While the different figures produced under the two regimes won’t mean any change in the real-world efficiency and emissions of the vehicles, it will have an impact on the amount of tax paid by company car drivers and their employers.

Sign up for our fleet policy guide


Advice for fleet managers

Fleet managers are advised to look at their choice lists to determine whether the new CO2 ratings could push certain vehicles into new BiK tax bands, or exceed the maximum emissions allowed under their policy.

If driver choice is being impacted, this may prove to be a good opportunity for a wholesale policy review and an assessment of the suitability of the ever-growing range of alternative fuel vehicles now available.

To read more about the new WLTP testing regime click here.

To find out how CLM can help to optimise your fleet strategy click here for more information or contact us for a no-obligation chat.