Quote:
Originally Posted by para transit fellow
With a trolley bus, I believe you still need a contingency fleet of diesels.
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While the need for a contingency fleet of diesels seems logical, that is a must have only for trolleybuses without on-board batteries. I believe modern trolleybuses have came a very long way in terms of reliability.
For example, I believe that if a new trolleybus service is implemented, the feeder cables would likely be underground, increasing reliability due to less exposure to the elements. Also, it is possible to have feeder cables that are as reliable as the feeder cables that power the C-Train system. Personally, I am not sure how reliable are the cables that power the C-Train system, but I believe the contingency buses have been brought out were mostly due to track maintenance, collision on the track and LRT vehicle failure. I think the latest LRT power outage incident was the Alberta flood this past June.
Modern trolleybuses now have on-board batteries for off-wire operation for about two kilometers. Older trolleybuses don't have batteries, which means whenever there is a detour that made trolleybuses impossible to manoeuver without causing a mess on the overhead, backup diesels would have to be brought out. That should not be a problem with modern trolleybuses as long as it can go off-wire for less than a kilometer. If a big truck snag an overhead, it can shut down a small section of the overhead circuit, but modern trolleybuses can continue to operate without power until a still-energized section of the overhead is reached where it can be rewired.
Modern trolleybuses can automatically lower its poles down quickly when a dewirement is detected. This would prevent the poles from tangling the overhead wires and pulling them down.
In my opinion, I think that due to the reasons described above, having contingency buses to back up a modern trolleybus fleet does not seem to make a lot of sense.