TESTING, TESTING...

You may have heard the acronym ‘WLTP’ mentioned in the motoring media recently. But what does it mean exactly? And how will it affect you? Our simple guide tells you everything you need to know.

WLTP stands for ‘Worldwide Harmonised Light Vehicle Test Procedure’ and as the name suggests, it’s the new global standard for testing the emissions and efficiency of all cars sold new today. It’s been designed to replace the old NEDC (New European Driving Cycle) test that the industry has used for years - and unlike its predecessor, has been designed to more accurately reflect how cars are actually used in real life. Going forward, this means that quoted MPG figures should more accurately match what’s achievable under normal driving.

WLTP testing features much more ‘on road’ driving and will also take into consideration available features and options on a vehicle. From air conditioning to electric seats, every additional feature adds to the weight of the vehicle and, combined with its usage, ultimately affects emissions and fuel economy. WLTP ensures that the use of such features is clearly recognised in testing, providing a more accurate view of how the consumer would use their car in real life.

What this means in effect is that after re-testing many vehicles emissions figures will appear to have risen, despite those vehicles producing the exact same amount of Carbon Monoxide (CO2) and Nitrogen Oxides (NOX) as they did before but will now take into consideration the additional weight from optional extras. In some cases, MPG figures may take a small tumble, too – as a result of cars being driven harder and more ‘realistically’ during the new test cycle.

The main difference between the two tests is that WLTP is far more stringent; with a much longer test drive aspect, higher maximum speeds on test, a longer test cycle and a greater number of actual test demands. Even details like the variance of gear shift points are now taken into account, to make sure that the powertrain sees everything from a gentle commute to a spirited motorway blast.

WLTP has been introduced to allow all car buyers to see emissions data that more accurately reflects the type of driving that they’re likely to achieve – and therefore allow them to make a better-informed decision on the environmental credentials and fuel economy of their chosen car before they buy. What this may also mean, going forward, is that the Road Fund Licence (or road tax) and company car tax for a model may go up, as these are currently based on what comes out of the tailpipe. For every car under the new protocol, that’s most likely to be higher.

Although WLTP has actually been applicable for all new model introductions since September 2017, it became compulsory to all new car registrations from September 2018. Any new model introduced after this time must conform to the new guidelines, but the EU has made allowance for any older models that don’t conform to be sold for up to one more year afterwards.

Fast-forward into the future and by 2020 the entire European car market will have one single, simple WLTP-CO2 standard to allow manufacturers, purchasers, legislators and fleet managers to accurately compare and target each and every car on sale. Although the figures will have changed, the cars themselves remain exactly the same. It’s simply the test that governs them that has changed. It’s fair to say that Europe still leads the way in ensuring that the vehicles on its roads are the cleanest on the planet.

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