On one hand, battery busses require lithium and rare earth metals which needs to be mined from a relatively short supply, as well as lots of fancy chemical processing which I’d wager produces plenty of byproducts, and batteries have a limited lifespan before needing to be replaced. On the other hand, trolley busses (the kind that gets power from overhead wires) require extensive infrastructure in the form of wires and poles, which require tons of metal (though much more abundant steel and aluminium) to produce and energy to install and maintain, and the wires also wear out from friction and also need to be replaced from time to time. Anyone know any papers comparing the sustainability of these two technologies? I’m also interested in how the wire-to-wheel energy efficiencies compare between them.
I don’t know a study on that, but given that they are experimenting in quite a few places with overhead lines on highways for use on battery-powered trucks, a hybrid solution must at least make economic sense (on paper).
Hybrid is the way to go until we can be figure out better battery tech
Yes this.
The best way to store energy is as fuel. You can even convert your electricity to fuel, and carry it in a fuel tank on the bus.
I’d like to see a comparison between electric (overhead wire) and diesel (series hybrid) trains though. Why has there been a cultural transition from diesel to electric? There must be some advantage.
I was talking about a battery + overhead lines hybrid though.
I don’t think normal petrol engine hybrids with a full conventional drive-train make ecological sense. They are too heavy and costly to produce & maintain. One of the big advantages of electric cars is that other than the complex battery technology they are really simple to build.
However a full electric + fuel-cell type of car as Toyota is currently experimenting with, might make sense at some point if they can build the fuel-cells cheaply with common metals.
Yes fuel cells could be great in the future.
I’ve never heard of a “battery + overhead lines hybrid”. How does it make sense? If you have a battery then you wouldn’t charge it with overhead lines, you’d use a charging station. If you really don’t have enough charge for one journey, your second choice would probably be a removable locomotive or a removable battery.
Petrol/diesel hybrids don’t need a conventional drivetrain. That’s the beauty of it. I can go into details if you like but there are several flavours of hybrid. You can have a lighter, more powerful, more reliable, more efficient, more ecological vehicle. And this is all really old and common technology. I just don’t see why pure electric is suddenly in fashion this decade. Batteries are getting better but so is everything. It doesn’t suddenly have a new capability it didn’t have 50 years ago.
Its for trucks. They run via the overhead line while on the highway, and when they leave the highway they use the battery.
So you have all the expense/weight of needing a huge battery on the lorry. And you have all the expense/maintenance putting infrastructure along the highway.
It sounds like the worst of both worlds. I can’t think of any major advantage to this approach, that would make it worthwhile.
Not easier to just put charging stations on the highway?
You can’t really put a large enough battery into a truck and by putting the overthead lines you can charge while driving.
It being experimented with in serveral places, so I am pretty sure that it makes sense economically speaking at least.
Agree with this. Might as well just have freight rail + battery trucks at the end points.
Actually, I just thought of this: I (fairly rarely) see the trolley busses in my city driving with the wires detached, so they also have batteries presumably in case of emergency. But I don’t know what their battery only ranges are, so I don’t know if they have smaller batteries, or if the batteries last longer due to not being used most of the time?
My guess is that some of the wired buses don’t have batteries. More than once I’ve seen the ones around me come off their wires and stop, blocking multiple lanes of traffic (it happens in turns), to reattach. I imagine protocol would be to drive to a good stopping point before reattaching if that were possible. They were also in heavy use before any kind of practical battery vehicle hit the roads.
Yeah trolleybuses have been around a pretty long time (particularly in really hilly cities like Seattle and San Francisco). Lots of transit agencies are experimenting with battery-electric buses, but trolleybuses (or some sort of hybrid trolleybus with a ~10 mile battery range) could probably work well for a lot of projects.
Like you mention, one of the major issues is the bus getting detached in a turn, but using them on routes with few turns and plenty of range to get things lined up would go a long way on that.
There’s some discussion below on trolley buses, although Toronto specific. Seems like trolley buses have had a very short range battery for a while now, in case of emergency need to go off wire. Also, the issue of detachment appears to be more about operational maintenance, the below suggests that Vancouver has been good at minimizing wire detachments. Also, interesting to note that the average life-cycle of trolley buses is 20-24 years as opposed to diesel buses which is around 10-14. I’m not sure where ebuses would fit in, since we haven’t yet had enough testing of them yet.
https://stevemunro.ca/2021/03/05/are-ebuses-the-answer-to-everything/
