Starting next month, Europe will implement the first phase of new fuel economy and emissions standards that were intended to take effect worldwide.

Automakers are required to release initial ratings based on lab tests using the Worldwide Harmonized Light Vehicle Test Procedure (WLTP) on Sept. 1, followed next year by the results of new real-world tests. By 2020, the WLTP ratings will take full effect.

Since other countries have pulled out of the system, Europe is going it alone with the WLTP standards, at least for now, though they may still have an impact on cars sold elsewhere.  

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Like changes that the EPA made to update U.S. fuel economy labels in 2008, the WLTP aims to make European fuel economy labels more realistic. They are also expected to result in shorter range estimates for electric cars than the old tests.

The more realistic test results are expected to impact car owners across Europe by increasing taxes and registration fees which in some countries are based on cars’ fuel consumption ratings. British auto magazine Car noted in a May report that current labels can be inflated by as much as 25 percent.

Considering electric-car range estimates, for example, the 2018 Nissan Leaf gets a 151-mile range rating from the EPA. Under old European standards, it was estimated at 235.5 miles of range. Under the WLTP tests, it is expected to be rated at 167.7 miles.

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The pending ratings are among the reasons some European auto executives have cited for building more plug-in and electric cars and fewer diesels. As European automakers devote more resources to building more plug-in and electric cars for Europe, it is likely to affect what types of cars are sold in other countries around the world as well.

The new WLTP tests will cover longer routes (14.4 miles over 30 minutes vs 6.8 miles over 20 minutes on the old NEDC tests), at higher speeds (up to 81.3 mph from 75 mph), and at more consistent temperatures to even out air conditioning loads.

Also, as with test procedures in the U.S. following the discovery of the Volkswagen emissions cheating scandal, the new WLTP test protocols in Europe will include testing in real-world on-road driving with mobile test equipment, fallout from the cheating scandal that cost Volkswagen billions.

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The United States pulled out of the worldwide agreement in 2011, a few years after making similar changes to its own fuel-economy rating and emissions system by adding a faster highway-driving cycle, a cold-weather test, and a hot-weather test that taxes cars’ air conditioning systems.

“Harmonization is one of those dreams we don’t think will ever come true,” Chris Nevers, Climate and Fuel Economy Director at the Alliance of Automobile Manufacturers told Forbes in 2016. “EPA and CARB won’t want to give up the authority they have over the emissions that are important here.”

In the same Forbes report, author and automotive analyst for Navigant research Sam Abuelsamid notes that the only way emissions and fuel-economy standards for cars are ever likely to be harmonized across the globe is when all cars run on electricity.  

—By Peter Telschow