Solarpunk Travel

I think coaches refers to longer distance bus-travel... like greyhounds in the US.

The reason regular bus travel is so bad in that graphic is that it is counted per passenger and these inner-city buses drive a lot of the time with few passengers. But if you want to keep servicing out-laying districts and non-rush hours there is little to do about that (although often these buses are over-sized).

I admit not having read the full study that lead to that graph, but I think I do understand the graph itself:

Buses are local public transport (intracity), commonly run by the government/municipality/etc. They run no matter what. Maybe at some point they will abandon the line, but it is a public service, so they won’t be doing that easily.

Coaches are long distance (intercity) travel, usually run by a private company, and if it’s not profitable they’ll just cull it. You have that in the US, it’s the Greyhound, which is now run by Flixbus.

If you look at the graph, buses do not generally lose out to cars, only to cars with 4 people on it.

Now a bus that runs 24/7 has a lower average utilization, because e.g. at night you might be the only passenger. If you compare that to a fully loaded car, sure, the car is better.

And the long distance bus (coach) doesn’t have to stop every 500m, so you’ll have way less fuel spent on braking and accelerating compared to a bus.

It’s actually impressive that despite the many times a public transport bus runs at low utilization it still is better than a car with just one person on it.

A coach, on the other hand, will have a better average utilization, since they will just immediately shut it down if there’s only one person using it.