The gap between real-world vehicle fuel consumption and official ratings is now at an all-time high in Europe — with the discrepancy now resting at around 42% — according to a new report from the International Council on Clean Transportation (ICCT).
Accordingly, real-world carbon dioxide emissions are also much higher than official ratings suggest — meaning that greenhouse gas emissions associated with vehicle use in Europe are much higher than is officially acknowledged.
As noted by the ICCT, the gap between official measurements of vehicle efficiency and actual performance of new cars in everyday driving in Europe has increased more than fourfold since 2001 — equating to around €400/year in extra fuel costs for the average owner/driver.
Perhaps more importantly, the gap also means that “less than half of the on-paper reductions in CO2 emission values since 2001 have been realized in practice.” Notably, a separate analysis by the ICCT found that there are similar gaps between official and real-world CO2 emissions in other major countries (even if perhaps far less pronounced than in Europe) — such as the US, China, and Japan.
“However, since 2001 Europe has seen the largest increase in the gap,” explained Dr Peter Mock, Managing Director of ICCT Europe.
“We analyzed data for more than 1.1 million vehicles from 8 European countries, and all data sources confirm that the gap between sales-brochure figures and the real world has reached another all-time high,” stated Uwe Tietge, a researcher at ICCT Europe and lead author of the study. “When we published our first study in 2013, the gap had widened over 10 years from roughly 10% to around 25%. Now it has increased to 39% for private cars, and 45% for company cars.”
The press release provides further information: “The analysis draws on data from 14 different sources: the user websites spritmonitor.de (Germany), HonestJohn.co.uk (United Kingdom) and Fiches-Auto.fr (France), the fleet management and fuel card companies Travelcard (Netherlands), LeasePlan (Germany), Allstar fuel card (United Kingdom), and Cleaner Car Contracts (Belgium and Netherlands), the car and consumer magazines AUTO BILD (Germany), auto motor sport (Germany and Sweden), the vehicle testing organization Emissions Analytics (United Kingdom), the car website km77.com (Spain), and the car club TCS (Switzerland).
“Manufacturers measure vehicle fuel consumption in a controlled laboratory environment. Since September 2017, a new test procedure, the Worldwide Harmonized Light Vehicles Test Procedure (WLTP), has to be followed for new vehicle types. From September 2018 onwards it will become mandatory for all new vehicles. The ICCT researchers expect that because the WLTP more accurately reflects real-driving conditions it will help cut the real-world gap approximately in half.
“’But even the new test procedure contains new loopholes that could permit the performance gap to increase again in the future,’ stated Dr Mock. ‘Further actions are therefore required, in particular on-road testing of fuel consumption and CO2 emissions under real driving conditions and a not-to-exceed limit for the real-world gap, as it already exists for air pollutant emissions today.’”
A good solution, according to the ICCT, would be to implement policy measures similar to the ones used in the US (which are responsible for the relatively limited gap present there) — in particular, independent surveillance testing of vehicles during actual real-world use.
“In the US, independent surveillance testing of actual vehicles on the road has been standard practice for many years,” explained Uwe Tietge. “It is no surprise that the increase in the real-world gap has been much lower in the US than in Europe. In fact, the fuel consumption values communicated to consumers in the US paint a very accurate picture of the average real-world fuel consumption.”
This is presuming of course that authorities in Europe actually want to remove the loopholes used by European auto manufacturers to avoid accountability — which is an open question.