Friday, 01 September 2017
UK toughens up emissions tests
Newly designed cars will start to be tested under the new regime over the coming months after the final piece of legislation specifying the requirements that allow testing authorities and manufacturers to prepare was published in July this year. This means consumers could start to see these brand new models arrive in showrooms from as early as next year. By 1 September 2018, all new cars on sale will have undergone WLTP testing and by 1 September 2019, all will have undergone the full RDE testing for both NOx and PN.
The new tests explained
More realistic driving behaviour:
• Higher average and maximum speeds
• Shorter stops
• Longer test distance and time
• Higher average and maximum drive power
• Test temperature set at 23°C
• Different gear shifts
• More rapid acceleration/deceleration
• Better range of driving to represent the city, urban, a road and motorway
• Fuel consumption and emissions figures that better represent results achieved by drivers
The test will measure:
• Fuel consumption
• CO2emissions
• Pollutant emissions
• Energy consumption for electric vehicles and plug-in hybrids
Real Driving Emissions (RDE)
The WLTP is complemented by an on-road test called Real Driving Emissions (RDE), which will ensure the vehicle's lab test performance is matched on the road. RDE works by fitting equipment called a Portable Emissions Measurement System (PEMS) to the vehicle, which measures emissions while the vehicle is driven on the road.
Given the huge differences in temperature, road and vehicle conditions as well as driving styles, no lab test can ever replicate exactly what happens on the road. RDE testing will demonstrate that new cars' low emissions are achieved in these real world conditions.
RDE will also include some extreme driving conditions, rarely encountered by most motorists, for example carrying a heavy load up a steep hill at high speed in very low temperatures.
To allow for the margins of error in highly sensitive PEMS equipment and the test itself, there is a tolerance allowed on top of the laboratory limits – known as the conformity factor.
If the vehicle meets these requirements, as independently witnessed by a government-appointed independent approval agency, it will be approved for sale in Europe.