CO₂ Emissions calculation

Contact Info

• Digitransit Team

Documentation

Graph build import of CO₂ Emissions from GTFS data sets (through custom emissions.txt extension) and the ability to attach them to itineraries by Digitransit team. The emissions are represented in grams per kilometer (g/Km) unit.

Emissions data is located in an emissions.txt file within a gtfs package and has the following columns:

route_id: route id

avg_co2_per_vehicle_per_km: Average carbon dioxide equivalent value for the vehicles used on the route at grams/Km units.

avg_passenger_count: Average passenger count for the vehicles on the route.

For example:

route_id,avg_co2_per_vehicle_per_km,avg_passenger_count
1234,123,20
2345,0,0
3456,12.3,20.0

Emissions data is loaded from the gtfs package and embedded into the graph during the build process.

Configuration

To enable this functionality, you need to enable the "Co2Emissions" feature in the otp-config.json file.

//otp-config.json
{
  "Co2Emissions": true
}

Include the emissions object in the build-config.json file. The emissions object should contain parameters called carAvgCo2PerKm and carAvgOccupancy. The carAvgCo2PerKm provides the average emissions value for a car in g/km and the carAvgOccupancy provides the average number of passengers in a car.

Example configuration

// build-config.json
{
  "emissions" : {
    "carAvgCo2PerKm" : 170,
    "carAvgOccupancy" : 1.3
  }
}

Overview

Config Parameter	Type	Summary	Req./Opt.	Default Value	Since
carAvgCo2PerKm	integer	The average CO₂ emissions of a car in grams per kilometer.	Optional	170	2.5
carAvgOccupancy	double	The average number of passengers in a car.	Optional	1.3	2.5

Details

Changelog

OTP 2.5

• Initial implementation of the emissions calculation.