Definition
This category includes emissions from the transportation of employees between their place of residence and the workplace using the following means of transport:
- Cars
- Bus
- Train / subway
- Airplane
- Bicycle
- On foot
Emissions caused by working from home can also be accounted for in this category.
Accounting for employee commuting
Commuting can be calculated using one of the following three methods:
- Fuel-based method: Multiplying the amount of fuel consumed by an appropriate emission factor.
- Distance-based method: Multiplying the distance traveled by an emission factor for the mode of transport used. Multiplication by two to include the return journey.
- Average data method: Based on average data on commuter flows (e.g. average commuting distances, average means of transport used, average commuting days per week).
The fuel-based method is the most accurate, followed by the distance-based method and finally the average data method.
Companies should convert the daily commuting distance into an annual commuting distance by multiplying the daily fuel consumed or the daily distance by the number of trips during the reporting period.
Distance-based method
Required activity data:
- Total distance traveled by employees during the reporting period (e.g. passenger kilometers traveled)
- Means of transportation used for commuting (e.g. train, subway, bus, car, bicycle).
Emission factors required:
- Emission factors for each mode of transport (usually expressed in units of greenhouse gases (CO2, CH4, N2O, or CO2e) emitted per passenger kilometer).
Average data method
Required activity data:
- Number of employees
- Average distance traveled by the average employee per day
- Average distribution of means of transportation used by employees
- Average number of working days per year.
Required emission factors:
- Emission factors for each mode of transport (usually expressed as kilograms of greenhouse gas emissions per passenger per kilometer of distance traveled).
Data collection
Companies should collect data on the commuting behavior of their employees, e.g. through a survey. The survey data includes:
- The distance traveled by employees or the location of their home and office
- The number of commuting days per week and number of working weeks per year
- The number of days per week that employees use different types of vehicles to travel to the office
- Whether there are car pools and the average utilization per vehicle
- The amount of gas or electricity consumed by working from home.
Accounting for commuter traffic in the Climate Hub
Some predefined activities with emission factors are stored in the Climate Hub. You can enter the quantity here. The Climate Hub then calculates the emissions for you. If you would like to enter additional activities or use your own emission factors, you can do so by clicking the Add your own activity button at the bottom left. You can find a detailed description here.
Further information can be found in the Technical Guidance for Calculating Scope 3 Emissions of the GHG Protocol in Chapter 7: Employee Commuting from page 87.