From laboratory to road: A 2016 update

This 2016 update to a series begun in 2013 analyzes 13 data sources covering 15 years, six countries, and approximately 1 million cars. The analysis shows that, in the EU, the gap between official and real-world CO₂ emission values continues to grow—from 9% in 2001 to 42% in 2015.

Since 2001 average official CO₂ emission values of new European passenger cars have decreased by 29%. The rate of decline quadrupled after the EU introduced CO₂ emission standards in 2009.

But the official vehicle CO₂ emission values are determined by laboratory tests. As previous “From Laboratory to Road” reports, published in 2013, 2014, and 2015, showed, there is a gap between real-world and official CO₂ values that has been increasing over time.

For an average consumer the gap now translates into additional fuel expenses on the order of €450 per year. Since vehicle taxation schemes and incentive schemes for low-carbon cars are based on official CO₂ values, the gap may also lead to significant losses of tax revenue and a misallocation of public funds.

This update discusses a number of reasons for the increasing gap. Flexibilities in the type-approval procedure allow for unrealistically low driving resistances and unrepresentative conditions during laboratory testing (these flexibilities account for the majority of the gap in 2015). Fuel-saving technologies such as stop/start systems and hybrid powertrains also prove more effective at reducing CO₂ emissions during laboratory testing than during real-world driving. Lastly, the type-approval process fails to take into consideration auxiliary devices such as air conditioning and entertainment systems. These devices consume energy during real-world driving and thus contribute to the gap.

The key implication of the study is the urgent need for improved test procedures. While a new type-approval procedure, the Worldwide harmonized Light vehicle Test Procedure (WLTP), will be introduced in the EU in 2017, the WLTP will not close the gap on its own. On-road tests, similar to the Real Driving Emissions (RDE) test procedure for air pollutants, and in-use conformity tests of randomly selected production vehicles should also be introduced.

View or download (PDF) the press release.

Attachments
FactSheet_FromLabToRoad_ICCT_2016_EN.pdf
FactSheet_FromLabToRoad_ICCT_2016_DE.pdf
L2R2016_summary_statistics.xls

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