Topics/Environmental Issues

One of the major burdens traffic poses to society is its impact on the environment in means of air and noise pollution as well as the consumption of non-renewable materials. Much work is put into the development of solutions that reduce these harms. A traffic simulation should support such development by allowing to measure the amount of generated pollution and the amount of consumed fuel. SUMO (used for both, SUMO and SUMO-GUI in the following) includes models and interfaces that fulfill these needs.

In the following, the topic of "environmental issues" as seen from SUMO perspective is described in the following.

=User Interaction= Pollutants/noise/consumption is computed only if the user asks for it or if it is used for visualisation. Pollutants emitted by the simulated vehicles can be visualised using SUMO-GUI or be written into output files, both by SUMO and SUMO-GUI. The following output can be used: Further information can be found in the outputs' documentation.
 * trip information: in combination with the emissions device, the tripinfo output contains the sum of all pollutants emitted / fuel consumed during a vehicle's journey;
 * edge/lane emissions: these output files contain the pollutants emitted and fuel consumed at an edge / a lane, aggregated over a variable time span;
 * edge/lane noise: these output files contain the noise produced at an edge / a lane, aggregated over a variable time span.

A SUMO-vehicle owns the attribute " emissionClass " (see Vehicle Emission Classes). This attribute defines which emission model and which of its parameter sets shall be used to compute the emissions. The models' resolutions and coverage of the vehicle population differ among the emission models.

Currently, the noise model only distinguishes two vehicle types: passenger and heavy duty vehicles. The discrimination is done based on the vehicle's emissionClass ; if the vehicle belongs to a passenger emission class, the noise parameter for a passenger vehicle are used, otherwise those of a heavy duty vehicle.

=Models= SUMO includes the following emission models:
 * HBEFA v2.1-based: A continuous reformulation of the HBEFA v2.1 emissions data base;
 * PHEMlight, a derivation of the original PHEM emission model.

Both models implement different vehicle emission classes. These classes can be assigned to vehicles by using the vehicle type attribute " emissionClass " (see Vehicle Emission Classes). Available emission classes can be found within the emission model descriptions (HBEFA v2.1-based, PHEMlight).

The noise model is based on HARMONOISE.

'''Table: pollutants covered by models

=Research=

Emissions Modelling
The emission models implemented in SUMO re-use existing models and data bases. The first steps including an overview of fifteen reviewed models as well as the derivation of the HBEFA v2.1-based model are given in the deliverable "D3.1 – Traffic Modelling: Environmental Factors" of the iTETRIS project. The development of PHEMlight is described in the deliverable "Deliverable 4.1 - Extended Simulation Tool PHEM coupled to SUMO with User Guide (Draft)" of the COLOMBO project.

Emission-optimal Routing
Usually, route computation is performed using travel times as weights for the edges of a road network. But what if one would use the emitted pollutants instead? Would their emission be reduced? The first investigations on this topic were performed using a real-world network within the iTETRIS project and were reported in its deliverable D3.1. Further steps using real-world scenarios are given in, and. To gain deeper knowledge about the dynamics of the processes, later investigations (!!!,, ) were performed using synthetic scenarios.

Evaluation of real Traffic Management Actions
European authorities are forced by the "Directive 2008/50/EC of the European Parliament and of the Council" to assure certain air quality. Traffic management, usually operated by local authorities, has the duty to perform corrective actions that reduce road traffic's impact, if needed. MARLIS is a database that lists such actions performed by traffic management authorities. A proof-of-concept for simulating such actions using SUMO is presented in. Tomàs Josep Vergés used this approach to simulate and evaluate some of such actions in his Master thesis

=Further Resources=

Further Interfaces

 * The tool traceExporter.py converts SUMO's fcd-output into files that can be directly read by the PHEM application. A tutorial on generating trace files (including PHEM input files) using this tool is available.

Further Documentation

 * !!! gives advices on implementing an emission model into SUMO

Tools

 * emissionsMap generates a map of emission for a named or all emission classes by iterating over velocity, acceleration, and slope
 * emissionsDrivingCycle generates emissions for a vehicle by virtually following a driving cycle

Other


=References=