From an acronym obsessed motor industry, the important ‘WLTP’ is explained
From ABS* to ZE*, it does seem as though the world’s motor industry has created its own Dictionary of Initials, highlights Iain Robertson, but finding out the definitions, short of ‘googling’ them, can be a tedious nightmare, as WLTP takes a firmer hold.
CAFE, or Car Average Fuel Economy, and not your favourite place for either a Latte, or Cappuccino, has been a present order for each car manufacturer to attend to for several decades. In fact, it is a legal requirement for motor dealers to display the specific official consumption figures on each showroom model.
The figures have been arrived at through a comprehensive series of tests carried out in a number of authorised laboratories at industry proving ground locations like Millbrook (Bedfordshire), or MIRA (Motor Industry Research Association, Nuneaton), in the UK. They have resulted in Urban, Extra Urban and Official Combined fuel consumption results that are expressed as averages and have been regarded as a moderately dependable guide for the consumer.
Classified as NEDC (New European Driving Cycle), since 1992, it is part of European Vehicle Type Approval, a series of legislation that allows authorised vehicles to be sold officially in European countries. If they do not meet Type Approval standards, which allows them to be MOT tested after they reach their third birthdays, they can be described as illegal for operation on our roads. However, the tests deal not only with fuel economy but also exhaust emissions, dealing with regulated pollutants (CO, CO2 and NOx) and particulate emissions, such as soot.
Unfortunately, the NEDC methodology has invariably been criticised, usually by certain members of the motoring media, notably when conducting their own frugality tests and being unable frequently to meet the Official Combined figures. This should not come as a surprise, as the government’s guide figures are carried out clinically in a closed laboratory, as opposed to on the open road. An element of test ‘errors’ is inevitable.
Under pressure to make the Type Approval tests more realistic, a more complex series of tests was introduced around September 2017, masquerading under the handle of WLTP (World Harmonised Light Vehicle Test Procedure). In order to limit any confusion between NEDC and WLTP values, an extended transition phase was introduced from September 2017 to January 2021. During this period, and dependent on the country, the fuel consumption and CO2 values that are used for tax purposes, commercial brochures, leaflets and websites are either displayed as NEDC values, WLTP values, or both, but always the same for all manufacturers within a country. In this way, buyers have a standard measurement to compare vehicles from different manufacturers.
The World-wide Harmonised Light Vehicle Test Procedure (WLTP) measures regulated pollutants and consumption, the latter being displayed as l/100km (litres per 100 kilometres) in Europe or MPG (Miles Per Gallon) in the UK. Pollutant measurements are displayed either as g/km (grammes per kilometre), or as mg/km. The new procedure includes more realistic testing conditions, in order to provide better representative information of the real-world vehicle emissions and fuel consumptions to customers. The tests are supervised by the country’s type approval agency based on standardised driving cycles (time, speed, equipment, temperature, and so on), in the same way, for all manufacturers. The UK’s type approval agency is the Vehicle Certification Agency (VCA).
To be fair, the consumer is better served by the WLTP changes, as the actual test takes 30 minutes, rather than 20 minutes, over a 14.44 miles, as opposed to 6.83 miles test cycle, at an increased average speed of 28.89mph, to a maximum of similarly increased 81.39mph. The procedure also takes into account vehicle options, such as large diameter alloy wheels, transmission types and even trim levels.
The new WLTP test provides consumers with a more realistic overview of vehicle emissions because the testing conditions are based on a closer representation of actual driving conditions. In order to achieve a more representative view of CO2 emissions, the new homologation protocol includes both the standard equipment and all optional equipment on the vehicle. This leads to fuel consumption and CO2 emission values based on the aerodynamics, weight and rolling resistance of the configured vehicle, with all its equipment and options, once again giving consumers and businesses a more accurate view of the vehicle’s actual emissions and economy.
In addition, the WLTP has been developed using genuine driving data collected from around the world and therefore better represents daily driving needs. It was developed with the aim of being used as a universal test cycle. Therefore, pollutant and CO2 emissions can be compared worldwide. However, the European Union, where WLTP has already been rolled out, and other regions will apply the test in different ways dependent on their local laws and traffic regulations.
Unsurprisingly, the roll-out in the UK has added complications for both Inland Revenue and HM Customs and Excise, with accountancy firms unsure of whether to deal with their client needs using NEDC, or WLTP legislation. Standardisation of ‘homologation’ is the intended protocol that has now been accepted (mostly) in WLTP language. Considering that it is essential for company car users, upon whom Benefit-In-Kind (BIK) taxation is levied, adopting the revised process will introduce both winners and losers upon application. However, it will settle down and prove less problematic…until another group, or body, decides that a better system is required!
Conclusion: System changes can be expensive and the motor industry carries the costs initially, passing them on to the consumer by way of increased retail prices. Was a new practice necessary? Not really but, as it is here, it does offer positive values. (ABS* = Anti-lock Braking System; ZE* = Zero Emissions)