Study finds that the gap between reported and actual emissions in Europe is getting wider

According to a new study by the International Council for Clean Transportation (ICCT), real-world car emissions are approximately 14% higher than the reported figures.

The study found that over the past five years, despite advanced testing procedures aimed at preventing these discrepancies, the gap in the figures increased by 80& in five years. 

The ICCT has been monitoring these emission gaps since the early 2010s. In 2022, there was a 14% gap for vehicles registered in Germany, compared to 8% in 2018.

For the analysis, the researchers used CO2 emission data reported by the European Environment Agency and real-world fuel consumption information from over 160,000 combustion engine and hybrid cars, as reported by consumers on the spritmonitor.de website.

The revision of testing methodologies in Europe followed the 2015 “Dieselgate scandal,” where major automakers, including Volkswagen, were discovered to have used “defeat devices” to manipulate emissions ratings during lab tests. 

In September 2017, the Worldwide Harmonized Light Vehicles Test Procedure (WLTP), agreed upon at the UN level, was introduced to provide a more representative assessment of real driving emissions than its predecessor, the New European Driving Cycle.

Despite this, the study indicates that the gap between testing and real-world emissions is widening again. According to WLTP, reported car CO2 emissions values decreased by 7.3% between 2018 and 2022. However, the study found that real-world emissions only decreased by 2.3% during the same period. 

Under the 2021 EU legislation, new vehicles are mandated to use ‘On Board Fuel Consumption Monitoring’ (OBFCM) devices, which track emissions performance in real-world conditions. This data is expected to inform CO2 monitoring starting in 2030. 

Jan Dornoff, research lead at the ICCT and co-author of the report noted, “Without counteraction, official CO2 emission values will become increasingly unrepresentative of real-world values. This will undermine the EU’s efforts to reduce transport-related CO2 emissions and result in consumers paying more for fuel than anticipated.”

“A correction mechanism can ensure that the CO2 emissions reduction targets that manufacturers must meet in the coming years are proportionally updated in accordance with the intended original stringency written into the law.”