THE NEW EUROPEAN Driving Cycle (NEDC), measures CO2 and pollutant emissions of vehicles against EU regulations.
Having a standardised testing procedure allows us to compare emissions between different car models.
The NEDC was developed in the 1980s and is now considered outdated because vehicles manufactured nowadays feature technologies – like four-wheel drive and air-conditioning – that affect fuel consumption (and with that consequently, CO2 emissions).
Furthermore, the NEDC has become thoroughly discredited since the emergence of the Dieselgate scandal.
The new regime
There is now a new emissions test called the World Light-duty Test Programme (WLTP) and as of 1 September 2017, all entirely new models or significantly upgraded cars sold in Europe must go through the WLTP before being approved for sale.
In conjunction with this new emissions test, there is a new RDE (Real-Driving Emissions) test for diesel NOx emissions and particulate numbers from gasoline cars. It is a real-world test in which the emissions are measured using a portable emissions monitoring system.
The test is said to be more representative of real-world driving than a laboratory test – but slightly less reproducible. However, it requires the car to be tested under a wide range of operating conditions testing the technology in a range of ways.
How is it different?
Like the old NEDC, the new WLTP is conducted in a lab (to ensure accuracy and repeatability), but has much more representative testing conditions based on data from ‘real driving’ for new cars and provides a more accurate basis for measuring emissions and calculating a car’s fuel consumption.
The WLTP recognises factors such as the mass and aerodynamics of the vehicle, the rolling resistance of the tyres and the impact of options fitted to the car by the manufacturer.
Whereas before, the certificate of conformity (COC) used to cover an entire model range, each individual car will now get its own conformity certificate, and its own specific emissions rating.
These new tests aim to give buyers comprehensive and reliable emissions and fuel economy figures so buyers can compare and select the best powertrain technology and car suited to the type of driving they do.
What does this mean for your car?
Most cars tested under WLTP and RDE are likely to show higher CO2 emissions and lower fuel economy figures than the same car tested under the NEDC test. To be clear, the new test will not increase a car’s emissions or fuel consumption – it will just more accurately reflect them.
Cars tested under WLTP will still have NEDC CO2 and fuel consumption values reported until 2020 and manufacturers have a grace period to adjust and get older models tested. The WLTP will not apply to all new cars until 1 September 2018 and the RDE until 1 September 2019.
The Government has not yet changed the Irish motor tax rates or VRT system to reflect the new WLTP tests but the EU has that the new system must not add to the costs for the consumer. However, with the new test likely to show higher CO2 emissions this will push cars up into higher tax bands unless our current system is adjusted.
The new tests have been welcomed by the motor industry with Mike Hawes, SMMT Chief Executive, saying:
These new and demanding tests will soon give consumers emissions performance information that is far closer to what they experience behind the wheel – and inspire greater confidence that the new cars they buy are not only the cleanest, but the most fuel efficient ever produced.
Greg Archer, director of clean vehicles at T&E, said:
The introduction of the WLTP and RDE tests marks an important milestone in the battle to ensure cars comply with environmental limits on the road and to end the cheating that has become endemic in emissions testing.
Here’s how the new WLTP test differs from the old NEDC test, in a graphic. To view a larger version tap here.
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