Estimating real world emissions from passenger cars - use and limitations of instantaneous emission data

In recent years, many measurements of emissions on chassis-dynamometers hav e already incorporated the online measurement of emission concentrations at the exhaust as standard, alongside the usual average values. These data co llected with a high time resolution (e.g. 1 second) can be combined with th e likewise modal-recorded operating condition of the vehicle (engine load) and serve as a basis for methods of calculating emission. Compared to the w idely used characterization of a driving pattern by its average speed only, the explicit dependence of the emission behaviour on the engine load allow s to take into account the level of dynamics of each driving situation indi vidually. A reliable emission data set gives the possibility of calculating emissions for different real world driving conditions. For many applicatio ns, it is thereby no longer necessary to carry out costly and time-consumin g chassis-dynamometer tests. Generation of emission data sets takes place o n chassis-dynamometers using different driving patterns. Systematic investi gations should show the requirements necessary for generation of instantane ous emission matrices, and how important a reliable consideration of drivin g kinematics is in estimating emissions for real world driving accurately.