Here, we pull back the curtain and show you how our CO₂ calculator works. At its core, the app relies on trusted data sources such as Framtiden i våre hender, Statistics Norway (SSB) and Bybanen. By combining these sources, we ensure that every calculation is reliable, transparent, and customized to the most common transport choices for students in Bergen. While our academic paper goes into full detail, we present a simplified version of the methodology here. Using collected data and clear formulas, the app estimates carbon emissions from different modes of transport.
The goal? To help you understand the environmental impact of your daily travel and make it easier to choose greener options. Click the buttons below to explore our full methodology paper, or jump straight to the Carbon App to try the calculator yourself.
How We Calculate Emissions:
\[CO₂ = d * ef\]
\[Ef = x * Ec\]
The Data Behind the Calculations:
Air travel is the most carbon-intensive mode of transport. Emission levels vary by travel class (Helle, 2025):
Rail travel is one of the most sustainable transport options. Emission levels vary by train type (VY, 2023; Helle, 2025):
Light rail travel in Bergen is a low-carbon option (Bybanen AS, 2023; Skyss, 2024):
We calculated this value based on an average trip length of 9 km and total passenger kilometers per year.
First, we find the total CO₂. Then we show the climate impact per
person by dividing by the number of passengers you select:
\[CO₂ = d * ef / passengers\]
Electric scooters are a convenient and low-carbon option for short trips in Bergen (Spencer, 2021):
The total life-cycle CO₂ emissions are low, we therefore use 0 g CO₂/pkm in our calculations.
Ferries are an important part of Norway's transport system (Helle, 2025):
Passenger figures exclude cars, which add about 377 g CO₂/km
Buses are a common transport option for students in urban and regional areas (Helle, 2025; Vy, 2023):