Real-Driving Emissions Regulations and their Implications

More effective legislation for emission regulation in new light vehicle powertrains

It is hoped that the transition from the NEDC to WLTP emissions testing cycles will make a significant contribution towards reducing the environmental impact of light passenger vehicles. However, emission measurements under real-world operating conditions will increase the variability of values recorded when compared to laboratory test based determinations. The EU emissions legislation has introduced Real Driving Emissions (RDE) within Euro 6 for vehicles operating on European roads as a new, additional assessment at both type approval and throughout the typical lifespan of a vehicle. To ensure OEMs integrate emissions control technologies under their offerings, the RDE legislation is being rolled out in four packages. The first three RDE acts came into force on 1 September 2017 for new cars built. The fourth RDE act will allow proper in-service conformity and market surveillance, including adequate third-party testing, on individual vehicle information that is required to carry-out WLTP and RDE tests. In a recent update in March 2018, the fourth act retains the Moving Average Window methodology to verify RDE trip normality, which requires the vehicle tested under RDE to also be tested on WLTP to obtain the reference CO2 emissions curve.