As with most things in life, making the green choice isn’t always straightforward. Sustainability is a complex and nuanced topic – and as much as we all love simple solutions and easy wins (more of these please?), we can only make the correct decisions once we’ve got all the facts. In our new series Green myth busting, I’ll be doing a deep-dive into assumptions we have around certain sustainable behaviours and choices, and teasing out some of the complexities. First up: train travel vs. car travel.
The perception: Taking the train is always better than driving
The carbon footprint of your train vs car travel depends on a number of factors: how many cars you’ll be taking off the road as a result of opting for the train, what class you’ll be travelling in on the train, and what type of train / car you’re in.
According to Mike Berners-Lee’s How Bad Are Bananas, the carbon emissions of travelling a mile by train per passenger can vary from 22g CO2e (a train run of nuclear energy in France) to 80g (a UK intercity train).
Seeing those numbers, it’s hard to imagine how the emissions of car travel can compare. But you’ll see from the tables below that this is actually a much more nuanced topic than it first appears:
CO2e numbers include embodied emissions of the car.
Driving any kind of car with just one passenger will emit much more CO2e than getting the train. But it turns out, driving a fully-packed LEV and EV actually results in lower emissions per person than travelling by train.
The class you travel in on the train matters too:
Travelling first-class doubles the carbon footprint of your travel, because there’s typically half the number of seats in a first-class carriage. So if you were able to pack your average UK car with four passengers going the same way, your travel would be less carbon-expensive.
Watch out for those embodied emissions!
The numbers we’ve just thrown at you include not only the carbon that is emitted while the car / train is in motion, but also its embodied emissions. Embodied emissions refer to the total amount of CO2e that is generated when something is being manufactured – i.e. the extraction of raw materials, the transportation and refinement of those materials, the emissions involved in the production of the product, etc. etc.
Taken from this perspective, the emissions that we generate from the actual usage of our products and services is just one part of our total carbon footprint. If we’re going to meaningfully reduce our emissions, we need to take into account every stage of our products / services' life cycle, including their embodied emissions.
Depending on what kind of car is being manufactured, its embodied emissions can be anywhere between 8 to 51 tonnes of CO2e (How Bad Are Bananas)– and this is before it even hits the road! That's why if you really need a personal vehicle, and you've got a petrol car that still works, it's better to keep driving it until the end of its life instead of swapping it for a new EV immediately.