On-Board Monitoring of Emissions in the Future Euro 7 Standard

The proposed Euro 7 emission standard foresees that the emission behaviour of Euro 7 vehicles is monitored via an on-board monitoring (OBM) system. In Euro 7 vehicles, OBM systems will monitor the emissions of nitrogen oxides (NO_X), ammonia (NH₃) and particulate matter (PM) for every trip through a combination of measured and modelled data. Sensors employed to support on-board diagnostics (OBD) in current vehicles may be used to support OBM.

According to the Euro 7 OBM concept presented in this paper, OBM will serve a dual purpose: the first is to warn the user of a vehicle about the need to perform repairs on the engine or the pollution control systems when these are needed. If these repairs are not performed in a timely manner, the OBM system will be able to ultimately prevent engine restart, akin to the existing low-reagent driver warning system in some compression ignition vehicles. The second purpose of OBM is to monitor the compliance of vehicle types with the emission limits. To that end, OBM systems will calculate an approximation of the distance-specific trip emissions at the end of each trip. A random selection of these trips will then be periodically transmitted in an anonymous way to the authorities. This will allow them to compare average trip emissions for a particular vehicle type to the relevant limits.