3 ms·

> Caternary lines have always seemed like a good solution but there must be a good reason they aren't more popular What reason?

jacquesm 4y ago
Ugly, expensive, maintenance headache. What's not to like... They are however more environmentally friendly than diesel engines and it works well if you only have a few well trafficked routes. But you can't do this for a whole city, and garbage trucks and snowplows need to go into every street, not just the main boulevards.
- wolverine876 4y ago
  Agreed on all points, though I notice everyone says they are so expensive and hard to maintain, but nobody cites anything (not a criticism - I have no idea myself). However, you don't need availability on every street, just enough to charge the vehicles sufficiently for the smaller streets.
  - jacquesm 4y ago
    Arnhem in NL and Riga in Latvia, both cities I spend a lot of time in still have them, but I wonder for how long. They're pretty iconic but every few years there is debate about whether or not it is still worth it. Another problem I forgot to mention is that these systems are not very flexible in dealing with mishaps, you can't overtake another trolley bus so if one has a problem the whole system grinds to a halt. An ICE bus just goes around the obstacle and continues.
    - wolverine876 4y ago
      I agree about the trolleys on rails and obstacles, which I've seen for myself, but electric vehicles would likely have some battery and run on tires, allowing diversions from the route. Anyway, I'm guessing it's been considered and I'd love to see the study.
      - jacquesm 4y ago
        I've been reading a bit more about it in the meantime: so, the trolley network in Arnhem is slowly diminishing in size, but it's still there and it will likely be there for quite a while to come. They are looking at ways to use a combination BEV / trolley system to allow the buses to recharge when they're on the line so they can depart from the route for longer stretches. The maneuvering in case of trouble situation is covered by a tiny diesel engine that can move the bus around to the point where it can reconnect to a working segment of the network. One problem with reducing the coverage is that it is relatively easy to take away the lines but the poles are in large chunks of concrete and not easy to remove at all.
        Robotbeat 4y ago
        I think that battery vehicles with substantial batteries (and so could be run on lines without ANY overhead infrastructure in a pinch) but that usually charge via overhead lines on a portion of the route is the ideal option. No charging time, no massive new infrastructure (the catenary only needed on a small fraction of total served lines) but also full flexibility. Actually better than fossil fuel variants which need usually to be refueled at the end of the shift at a depot or whatever.
        jacquesm 4y ago
        Yes, it certainly looks like a very clever solution. I know they tried the same thing with a flywheel based bus but that ultimately did not work out. Let's see how this works in practice.
        Robotbeat 4y ago
        It helps that batteries have literally two orders of magnitude greater range than an old school flywheel.
        jacquesm 4y ago
        Yes, definitely, they are trialing this in Arnhem, I'll go have a look at it to see how it is all put together. By the looks of it they take a 'normal' trolley bus, remove diesel engine + tank + associated bits and pieces then put a battery in the spot where the tank used to be, and a bunch of electronics (regulator/inverter/charger) to create a voltage high enough to run the normal bus hardware of and to recharge the battery when the bus is connected to the overhead grid.
    - happyopossum 4y ago
      The buses I’m familiar with that use overhead power lines don’t use them exclusively - they have batteries or diesel for when they venture off the powered lines.
      - jacquesm 4y ago
        Interesting, I've seen them stuck more than once, I'll have to check up on what the deal is there, I walk by the depot every couple of days and I'm sure they'll be happy to talk about it.
      - wolverine876 4y ago
        I wonder what they do when a bus runs out of power - towtrucks? Charging trucks?
        dendrite9 4y ago
        The only ones I have spent a lot of time looking at are in Seattle and at least they used to all be diesel and could hookup to the lines or lower them to run off the lines. For pure electric I assume they must tow them away but I don't know enough about the failure modes. This is a good chance to share a link to the guy with a Prius modified to run on the bus power in San Francisco: https://thebolditalic.com/hacked-prius-running-on-muni-power-lines-the-bold-italic-san-francisco-80cdbe55d68e https://thebolditalic.com/hacked-prius-running-on-muni-power...
        kibwen 4y ago
        Extension cord into the nearest bodega? :P
    - prmoustache 4y ago
      Trolley buses in Lausanne are(were?) equipped with small auxiliary ice engines that would take over in case of loss of power. In the hills with passengers it was just enough for the bus to go at walking speed but that was enough to move out of the way or overtake a stranded vehicle.
      - pclmulqdq 4y ago
        The "E" in ICE means engine.
  - ClumsyPilot 4y ago
    > Agreed on all points, though I notice everyone says they are so expensive and hard to maintain, but nobody cites anything Because it's a complete fabrication -> every ton of conducting wire could replace 100 tons of battery in busses and trucks. It is also over 10 times cheaper per ton, so in material costs it is less than 1/1000th of the cost. The only issue is that the city needs to pay for the wire, but it does not know how to charge a large array of private companies that might want to use the wires, there is lack of standardisation and metering.

jacquesm 4y ago

Ugly, expensive, maintenance headache. What's not to like... They are however more environmentally friendly than diesel engines and it works well if you only have a few well trafficked routes. But you can't do this for a whole city, and garbage trucks and snowplows need to go into every street, not just the main boulevards.

wolverine876 4y ago
Agreed on all points, though I notice everyone says they are so expensive and hard to maintain, but nobody cites anything (not a criticism - I have no idea myself). However, you don't need availability on every street, just enough to charge the vehicles sufficiently for the smaller streets.
- jacquesm 4y ago
  Arnhem in NL and Riga in Latvia, both cities I spend a lot of time in still have them, but I wonder for how long. They're pretty iconic but every few years there is debate about whether or not it is still worth it. Another problem I forgot to mention is that these systems are not very flexible in dealing with mishaps, you can't overtake another trolley bus so if one has a problem the whole system grinds to a halt. An ICE bus just goes around the obstacle and continues.
  - wolverine876 4y ago
    I agree about the trolleys on rails and obstacles, which I've seen for myself, but electric vehicles would likely have some battery and run on tires, allowing diversions from the route. Anyway, I'm guessing it's been considered and I'd love to see the study.
    - jacquesm 4y ago
      I've been reading a bit more about it in the meantime: so, the trolley network in Arnhem is slowly diminishing in size, but it's still there and it will likely be there for quite a while to come. They are looking at ways to use a combination BEV / trolley system to allow the buses to recharge when they're on the line so they can depart from the route for longer stretches. The maneuvering in case of trouble situation is covered by a tiny diesel engine that can move the bus around to the point where it can reconnect to a working segment of the network. One problem with reducing the coverage is that it is relatively easy to take away the lines but the poles are in large chunks of concrete and not easy to remove at all.
      - Robotbeat 4y ago
        I think that battery vehicles with substantial batteries (and so could be run on lines without ANY overhead infrastructure in a pinch) but that usually charge via overhead lines on a portion of the route is the ideal option. No charging time, no massive new infrastructure (the catenary only needed on a small fraction of total served lines) but also full flexibility. Actually better than fossil fuel variants which need usually to be refueled at the end of the shift at a depot or whatever.
        jacquesm 4y ago
        Yes, it certainly looks like a very clever solution. I know they tried the same thing with a flywheel based bus but that ultimately did not work out. Let's see how this works in practice.
        Robotbeat 4y ago
        It helps that batteries have literally two orders of magnitude greater range than an old school flywheel.
        jacquesm 4y ago
        Yes, definitely, they are trialing this in Arnhem, I'll go have a look at it to see how it is all put together. By the looks of it they take a 'normal' trolley bus, remove diesel engine + tank + associated bits and pieces then put a battery in the spot where the tank used to be, and a bunch of electronics (regulator/inverter/charger) to create a voltage high enough to run the normal bus hardware of and to recharge the battery when the bus is connected to the overhead grid.
  - happyopossum 4y ago
    The buses I’m familiar with that use overhead power lines don’t use them exclusively - they have batteries or diesel for when they venture off the powered lines.
    - jacquesm 4y ago
      Interesting, I've seen them stuck more than once, I'll have to check up on what the deal is there, I walk by the depot every couple of days and I'm sure they'll be happy to talk about it.
    - wolverine876 4y ago
      I wonder what they do when a bus runs out of power - towtrucks? Charging trucks?
      - dendrite9 4y ago
        The only ones I have spent a lot of time looking at are in Seattle and at least they used to all be diesel and could hookup to the lines or lower them to run off the lines. For pure electric I assume they must tow them away but I don't know enough about the failure modes. This is a good chance to share a link to the guy with a Prius modified to run on the bus power in San Francisco: https://thebolditalic.com/hacked-prius-running-on-muni-power-lines-the-bold-italic-san-francisco-80cdbe55d68e https://thebolditalic.com/hacked-prius-running-on-muni-power...
      - kibwen 4y ago
        Extension cord into the nearest bodega? :P
  - prmoustache 4y ago
    Trolley buses in Lausanne are(were?) equipped with small auxiliary ice engines that would take over in case of loss of power. In the hills with passengers it was just enough for the bus to go at walking speed but that was enough to move out of the way or overtake a stranded vehicle.
    - pclmulqdq 4y ago
      The "E" in ICE means engine.
- ClumsyPilot 4y ago
  > Agreed on all points, though I notice everyone says they are so expensive and hard to maintain, but nobody cites anything Because it's a complete fabrication -> every ton of conducting wire could replace 100 tons of battery in busses and trucks. It is also over 10 times cheaper per ton, so in material costs it is less than 1/1000th of the cost. The only issue is that the city needs to pay for the wire, but it does not know how to charge a large array of private companies that might want to use the wires, there is lack of standardisation and metering.