As part of the Worldwide Harmonised Light Vehicle Test Procedures (WLTP), the Real Driving Emissions Stage 2 (RDE2) aims to capture a ‘real-world’ view of a car’s performance.
A big annoyance for many motorists when buying their new vehicle, is the disconnection between real-world fuel economy and the emission figures to what the manufacturer advertises.
When buying a new vehicle, or choosing your next company car, MPG and CO2 emissions are crucial.
To obtain these figures, all vehicles are subject to a test called New European Driving Cycle (NEDC) – a test that hasn’t been updated in 20 years! NEDC is conducted on a rolling road under laboratory conditions and is now viewed as somewhat unreflective of real-world driving conditions.
New tests aim to bring this frustrating problem be coming to an end.
In September 2017, new fuel economy and emissions tests were introduced. As part of European regulations, the new tests aim to improve air quality and tackle climate change by measuring fuel consumption, CO2, NOx, particulates and carbon monoxide.
Worldwide Harmonised Light Vehicle Test Procedures (WLTP)
The new test comes in the form of the Worldwide Harmonised Light Vehicle Test Procedures (WLTP). Part One of WLTP, much like NEDC, takes place in a laboratory environment. However, the new tests will be faster, longer, and more dynamic. WLTP tests the vehicle at a greater range of engine speeds, load, gear change, and temperatures.
WLTP also takes into consideration additional equipment such as larger alloys or heated seats which will make the vehicle heavier and impact their performance.
The below graphic shows the nine main differences between the new WLTP test for cars and the old NEDC procedure:
Real Driving Emissions Stage 2 (RDE2)
A brand new element to the test is the Real Driving Emissions Stage 2, known as RDE2.
The RDE2 section of the test means vehicles will also undertake a 90-minute real-world driving test to assess how the vehicle performs in real-world driving conditions. During the 90-minute test, vehicles will be fitted with emission testing equipment attached to the exhaust pipe.
In order to make test conditions reflective of the real world, vehicles will be required to do equal splits of town, countryside, and motorway driving during the test.
How will this benefit motorists?
The disconnection between real-world fuel economy and emission figures to what is advertised should gradually start to diminish. Therefore, buyers will become better informed when analysing a vehicles CO2 and MPG figures.
It has also been suggested that the previous test presented potential loopholes to manufacturers. ‘Dieselgate’ being an obvious example of this where manufacturers have been accused of optimising their results. Without these, manufacturers will need to ensure that their vehicles are as efficient and economical as possible.
Impact on fleet today
Although the new real-world driving test was introduced in September last year, motor manufacturers have the option of putting new cars through the additional real-world driving test. RDE2 will not be mandatory for all new cars until September 2019.
The Government has also confirmed that company car tax will not be affected until April 2020 when new WLTP-based bandings will be released, 6 April.
Vehicle Excise Duty (VED) has already been affected by WLTP as of April 2018 following the new diesel surcharge. Any new diesel car that complies to the RDE2 standard has a lower rate of tax compared to other diesels who don’t. However, the BVRLA reports:
“There are no diesel vehicles for sale today which meet RDE2 standards.
“From discussions with manufacturers we are unlikely to see vehicles which meet these standards for the next 12 to 18 months.”