CopertColdStrategy

Warning

This Strategy cannot be used by itself. It can only be used as a cold_strategy with the CopertStrategy or the HbefaStrategy.

The CopertColdStrategy implements emission calculation with the COPERT methodology for cold start emissions. It uses global assumptions about the average length of a trip (in km/h) and the average ambient temperature (in degrees Celsius) that are set in the configuration file.

Also in the configuration file you may specify some road types and area types that will be excluded from the cold emission calculation. This means that cold emissions will be zero for all vehicles at links that belong to the road types or area types that you want to exclude. Possible road types to be excluded are: MW_Nat, MW_City, Trunk_Nat, Trunk_City, Distr, Local, and Access. Area types that can be excluded are Rural and Urban.

The CopertColdStrategy takes the emissions from the hot strategy that is used in the CopertStrategy or HbefaStrategy as input. It uses the hot emissions to derive hot emission factors and to calculate total emissions.

Output of a model run with this Strategy are two csv files per pollutant:

  • cold start emissions
  • total emissions

Data requirements

What data the CopertColdStrategy requires depends on the mode set in the configuration file for the run.

Data requirements for mode berlin_format

All input data in berlin_format required by the CopertHotStrategy is also required for the CopertColdStrategy.

Additionally a file with cold emission factors is required:

../_images/cold_ef_table.png

How to read this diagram?

This is the cold ef table as provided by EEA recommendations.

  • Pollutant: One of the following: CO, NOx, or VOC.
  • VehSegment: A vehicle segment. One of the following: Mini, Small, Medium, or Large-SUV-Executive.
  • MinSpeed: The minimum speed the A,B and C values in this row are valid for.
  • MaxSpeed: The maximum speed the A,B and C values in this row are valid for.
  • MinTemp: The minimum temperature the A,B and C values in this row are valid for.
  • MaxTemp: The maximum temperature the A,B and C values in this row are valid for.
  • A: The A parameter for the cold ef calculation.
  • B: The B parameter for the cold ef calculation.
  • C: The C parameter for the cold ef calculation.

Example:

Pollutant VehSegment MinSpeed MaxSpeed MinTemp MaxTemp A B C
CO Mini 5 25 -20 15 0.563 -0.895 4.964
CO Mini 26 45 -20 15 0.842 -0.349 3.485
CO Mini 5 45 15   0.222 -0.876 10.12

Data requirements for mode yeti_format

All data in yeti_format required by the CopertHotStrategy is also required for the CopertColdStrategy.

Additional requirements:

  • A file with cold emission factors is required, as described above.
  • A vehicle mapping file is required. It needs to be in this format.

Supported Pollutants

CopertColdStrategy supports these pollutants:

PollutantType.CO
PollutantType.NOx
PollutantType.VOC

Set the pollutants for a run in your config file. For example:

pollutants:          [PollutantType.CO, PollutantType.NOx]

Make sure to include emission factors for the pollutants you are using in the emission factor data.

What to put in the config.yaml

If you want to use the CopertColdStrategy for your calculations, you need to set the following options in your config.yaml. Don’t forget to add the parameters specified here: Configuring YETI

If using mode berlin_format:

strategy:                     code.copert_strategy.CopertStrategy.CopertStrategy
load_berlin_format_data_function:     code.copert_strategy.load_berlin_format_data.load_copert_berlin_format_data
load_yeti_format_data_function:   code.copert_strategy.load_yeti_format_data.load_copert_yeti_format_data
validation_function:          code.copert_cold_strategy.validate.validate_copert_cold_berlin_format_files

berlin_format_link_data:              path/to/link_data.csv
berlin_format_fleet_composition:      path/to/fleet_composition_data.csv
berlin_format_emission_factors:       path/to/emission_factor_data.csv
berlin_format_los_speeds:             path/to/los_speeds_data.csv
berlin_format_traffic_data:           path/to/traffic_data.csv
berlin_format_vehicle_mapping:        path/to/vehicle_mapping_data.csv
berlin_format_cold_ef_table:          path/to/cold_ef_table.csv

ltrip:                        12  # the average length of a trip in km/h
temperature:                  15  # the average ambient temperature in °C
exclude_road_types:           [MW_City]  # Exclude multiple road types like this: [MW_City, Trunk_City]
exclude_area_types:           [Rural]    # Or: [Urban]

If using mode yeti_format:

strategy:                     code.copert_strategy.CopertStrategy.CopertStrategy
load_yeti_format_data_function:   code.copert_strategy.load_yeti_format_data.load_copert_yeti_format_data
validation_function:          code.copert_cold_strategy.validate.validate_copert_cold_yeti_format_files

yeti_format_emission_factors:     path/to/yeti_format_ef_data.csv
yeti_format_los_speeds:           path/to/yeti_format_los_speed_data.csv
yeti_format_vehicle_data:         path/to/yeti_format_vehicle_data.csv
yeti_format_link_data:            path/to/yeti_format_link_data.csv
yeti_format_traffic_data:         path/to/yeti_format_traffic_data.csv
yeti_format_cold_ef_table:        path/to/cold_ef_table.csv
yeti_format_vehicle_mapping:      path/to/vehicle_mapping_data.csv

ltrip:                        12  # the average length of a trip in km/g
temperature:                  15  # the average ambient temperature in °C
exclude_road_types:           [MW_City]  # Exclude multiple road types like this: [MW_City, Trunk-City]
exclude_area_types:           [Rural]    # Or: [Urban]