Stena Line measures the carbon emissions footprint of transported goods onboard our ships in the unit of gram CO2/ton-km. This common unit for emissions related to transport work allows you as a customer to benchmark emissions levels with other transportation modes.
To calculate the CO2 emissions caused by your shipment is based on three factors:
- The weight of carried freight, including vehicle tare (metric tons)
- One-way distance of the route (km)
- CO2 emission intensity of the route (gCO2/ton-km)
The CO2 emission intensity varies with different factors such as type of fuel, type of ship, weather, ship speed, allocation between freight and passengers onboard, and the total weight of freight units. That is why there is a difference between the CO2 emissions on different routes, which also may vary over time throughout the year, due to changes in our network and operations.
The CO2 intensity is calculated as the total emissions allocated to freight divided by the total amount of freight transport work done for each route. For the allocation of CO2 emissions, Stena Line uses the methodology described in the ISO 14083 standard.