Criticism
- Inability to represent real-life driving
- The NEDC was conceived at a time when European vehicles were lighter and less powerful. The test offers a stylized driving speed pattern with low accelerations, constant speed cruises, and many idling events, however the transient accelerations are much steeper and more dynamic in practice, in part caused by the power surplus of modern engines, as the 0-60 mph time decreased from 14 to 10 sec from the eighties to today on average. As a result, drivers fail to achieve the certified values in practice. A new version of the driving cycle should also be realistic towards the daily use of ancillary units and gadgets which tend to be fitted to modern vehicles.
- Cycle beating
- For the emission standards to deliver real emission reductions it is crucial to use a test cycle that reflects real-world driving style. However the fixed speeds, gear shift points and accelerations of the NEDC offer possibilities for manufacturers to engage in what was called 'cycle beating' to optimise engine emission performance to the corresponding operating points of the test cycle, while emissions from typical driving conditions would be much higher than expected, undermining the standards and public health. In one particular instance, research from two German technology institutes found that for diesel cars no 'real' NOx reductions have been achieved after 13 years of stricter standards.
Read more about this topic: New European Driving Cycle
Famous quotes containing the word criticism:
“However intense my experience, I am conscious of the presence and criticism of a part of me, which, as it were, is not a part of me, but a spectator, sharing no experience, but taking note of it, and that is no more I than it is you. When the play, it may be the tragedy, of life is over, the spectator goes his way. It was a kind of fiction, a work of the imagination only, so far as he was concerned.”
—Henry David Thoreau (1817–1862)
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—Mary Pickford (1893–1979)
“Good criticism is very rare and always precious.”
—Ralph Waldo Emerson (1803–1882)