Bus priority project manager Susan Jeynes analyses the latest transport emissions data to identify which modes are the biggest climate culprits.
Clear choices vs complex comparisons
Given that transport is the sector with the highest total emissions in Scotland, anyone looking to reduce their carbon footprint should consider how they make their journeys.
To some extent, the choices are clear – for example, walking will always have fewer emissions than driving. However, comparisons between other modes of transport are not always obvious.
Visual Capitalist recently published some interesting research that compared the carbon emissions of a wide range of modes of transport.
Clearly, this is not the whole picture.
It’s important to note that the average emissions data provided can vary based on several factors, including the fuel type used, the specific journey taken, and the occupancy rates of vehicles.
For example, the efficiency of an electric car depends significantly on the source of electricity, and the emissions from a bus or train can vary based on how full they are and whether they run on electricity or fossil fuels.
Similarly, the production emissions of EVs can differ depending on the materials and energy sources used during manufacturing.
However, there are some general conclusions that can be drawn from the data.
The worst performer
Flying is the most carbon-intensive mode of transport, with short-haul flights the biggest climate culprit.
It is important to note that emissions vary for different journey types – with short-haul flights emitting 246g/km CO₂, compared to 147 for long-haul flights.
This is because planes use significantly more fuel when taking off and landing, making shorter flights (trips between London and the Central Belt for instance) disproportionately polluting.
Cars: Petrol, diesel, electric
According to the research, petrol and diesel cars emit around 170g/km, while electric cars emit a quarter of CO₂e (47g/km).
This calculation considers only the emissions from fuelling the cars, including electricity generation for EVs.
When factoring in the manufacture of the vehicles, electric cars still come out ahead, but the difference narrows: 39 tonnes of CO₂ over an EV’s lifetime compared to 55 tonnes for a petrol or diesel car.
Despite the higher energy cost to build EVs, their use more than compensates for this over time.
Carpooling can further reduce emissions significantly.
Low-carbon options: Trains, trams, ferries & buses
Public transport options, namely buses, trains, trams and ferries perform the best in terms of emissions savings. For instance, the carbon footprint of buses is almost half that of petrol or diesel cars.
Trains, trams and ferries all emit under 35g/km, making them excellent choices for sustainable travel.
Increasing passenger numbers on all these modes only decreases their emissions further.
Making better choices
Deciding how to travel involves various factors including cost and convenience.
However, from a purely carbon emissions perspective, the data suggests we:
- Walk or cycle for short journeys.
- Take the train or coach for longer journeys whenever possible.
- Drive an electric vehicle (EV) if driving is necessary, and try to carpool.
- Avoid flying, especially for domestic travel within the UK.
Understanding the carbon footprint of different modes of transport helps make informed choices that can significantly reduce personal and collective emissions.
Walking, cycling, and using public transport are generally the most sustainable options, while careful consideration of vehicle type and travel necessity can mitigate the impact of necessary car travel.
By making conscious decisions, we can all contribute to a greener, more sustainable future.
