Statement from the German Association of the Automotive Industry on ICCT report “From laboratory to road”:
The introduction of a new testing cycle under more precise regulatory conditions and measurements on the roads next year will make the information more realistic in the future, and bring greater reliability for consumers. For many years now the automotive industry has worked toward a reform of exhaust and consumption measuring procedures, in order to reduce the differences between laboratory values and those on the road, which irritate customers.
The ICCT’s results are not based on measurements, but on data collected from sources such as private users and trade magazines, and are therefore reliable only to a certain extent. It is not new that emission values from vehicles in the laboratory and on the road are fundamentally different. The principal reason is the obsolete measuring procedure that no longer adequately reflects the reality of today’s models or road traffic. For example, it does not take into account standard equipment like heated seats and radios, and the acceleration is too gentle for today’s driving. There is also a purely mathematical reason why the gap appears to be increasing: because the vehicles are becoming ever more efficient, their values as measured in the testing cycle are constantly falling. If at the same time the additional consumption owing to features such as air conditioning and GPS remains constant, the resulting percentage deviation rises even though consumption is lower in absolute figures. Individual driving style also greatly influences fuel consumption and experience shows that fuel economy training brings about savings of around 25 percent on average due to a more suitable driving style.