WLTP

The Worldwide Harmonised Light Vehicle Test Procedure. What the changes mean for you and your busines

What is WLTP and what does it mean for you?

Under conditions defined by EU law, the WLTP laboratory test is used to measure fuel consumption and CO2 emissions.

WLTP is the vehicle testing cycle that aims to improve the accuracy of vehicle emissions
and fuel consumption figures provided by OEMs (Original Equipment Manufacturers). It replaces the outgoing NEDC (New European Driving Cycle) which has been in force since the 1990s and no
longer accurately reflects modern vehicle emissions or driving.

The changes at-a-glance

More realistic driving behaviour
A wider range of driving situations (urban, suburban, main road, motorway)
Longer test distances
More realistic ambient temperatures, closer to the European average
Higher average and maximum speeds and drive power
More dynamic and representative accelerations and decelerations
Shorter stops
Optional equipment: CO2 values and fuel consumption are provided for individual vehicles as built
Stricter car set-up and measurement conditions
Enables best and worst-case values on consumer information, reflecting the options available for similar car models

What are the differences between WLTP and NEDC?

The new WLTP procedures seek to replicate real world driving and align emissions to individual vehicles more accurately.
Testing time increases to 30 minutes with four driving phases instead of two. Speed, gear changes and distance travelled are all increased, whilst CO2 figures are tested at lower temperatures to portray a more realistic picture of a car’s emissions cycle.
WLTP tests recognise that some optional extras have an effect upon aerodynamics, weight and rolling resistance and will adjust CO2 and MPG values accordingly. Under the previous testing structure, optional equipment (larger alloy wheels, body styling, heated seats etc.) was not considered.

How does the new lab test compare?

NEDC

Duration: 20 minutes
Distance: 6.8 miles
Speeds: 21mph average - 75mph maximum
Gear shift points: Fixed
Test temperature:20-30 degrees

WLTP

Duration: 30 minutes
Distance: 14.4 miles
Speeds: 28.9mph average - 81.3mph maximum
Gear shift points: Different (depending on vehicle)
Test temperature:14-23 degrees

Test Cycle

Moving from a single test cycle, WLTP will introduce 3 different test cycles depending on the power-to-weight class of the vehicles. The appropriate cycle will then be used for the specific vehicle

Road Type

Going from 2 phases with NEDC, the new WLTP test will have 4 phases to represent: urban city, suburban, A road, and motorway

Influence of optional equipment

CO2 values will now take into account the weight and effects on aerodynamics of optional equipment such as air conditioning, tyres etc

CO2 and fuel consumption

Consumption measurements will now be closer to what drivers experience
on the road

Benefits of real world emissions testing
The Real-world emissions test is supplementary to WLTP, taking take into consideration:

Road Type
Weather
Conditions
Traffic
Conditions
Road Gradient

What does the change look like over time?

2018

SEPTEMBER every new car tested under WLTP.
DECEMBER government releases Review of WLTP and Vehicles Taxes consultation. Some manufacturers announced that their vehicles are RDE2 compliant.

2019

JULY WLTP consultation response.

2% reduction in CCT for new cars
Post April 2020 Freeze for existing cars
Zero tax on electric cars

SEPTEMBER WLTP figures used for all vans.

2020

JANUARY new car models must be RDE2 compliant to go on sale.
APRIL WLTP CO2 to be used for company car tax purposes & VED. New dynamic interfaces applied to get impact of options on CO2 and MPG. Corporation tax falls to 17%.