• WP4.1 Optimal road user charging
The optimal RUC depends on flows while the flows depend on the RUC. Finding the optimal RUC is a bi-level problem of route choice and toll optimisation and although the solution is known in principle, it is difficult to actually solve in complex networks. Solutions are however required for real practical applications of RUC. The project will develop meta-heuristics to solve the problem using the route choice models that are developed in WP3. As there are plenty of fall-back options in WP3, it is not considered a risk for WP4 that WP3 may not deliver.
• WP 4.2 Optimal road user charging under feasibility constraints
In reality, the design of RUC faces a number a number of technical, user related and political constraints. Therefore systems are designed using second best principles, and often by many trial-and-error calculations. This WP extends WP 4.1 to include feasibility constraints, seeking to develop general methods for finding near-optimal solutions.
• WP4.3 Preparation of policy papers
Based on the work in the project, this WP prepares a number of policy papers. These are succinct and clear papers that summarise the main research insights with an audience of policy makers in mind. The scope of the policy papers will include, at least, the scope of the IRUC project.
The project has access to a wide range of data sources. These comprise i.a. high frequency ANPR (automatic number plate recognition) data giving precise speed/flow measurements over a number of road sections; GPS data recording individual vehicle movements and association to GIS (geographical information system) data, one GPS dataset is from an experiment involving actual toll payments; register data concerning households, car ownership and usage, the national travel survey. In addition, all data from the construction of the National Traffic Model at DTU are available.
In general, the level of risk associated with the project is low since the level of ambition of most WPs can be scaled down in the face of irresolvable difficulties. The project is designed to be robust with respect to such instances.