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"The highway where trucks work like electric trains"

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SSR_317:

--- Quote from: bwana39 on November 27, 2021, 11:17:19 AM ---The city busses in  San Francisco operate like this.

https://www.sfgate.com/bayarea/article/Muni-trolley-wire-visual-pollution-electrifies-5056671.php

--- End quote ---
I've been on the Muni trolley buses, during visits to 'Frisco. The City by the Bay seems to have nearly every type of transit system known to mankind, except for High-Speed Rail (which is coming there, eventually).

Rick Powell:

--- Quote from: kalvado on December 01, 2021, 04:41:53 PM ---On a serious note, overhead wires limit vertical clearance for oversized cargo in a very unforgiving way.  That may be another thing to think about.

--- End quote ---

And the fact that trolley buses can keep their trolley poles or pantographs engaged fairly easily going 25-30 mph and driving carefully, but a caravan of trucks going 70 mph may not be that easy to do...and how could you switch lanes on a multi-lane highway, except at an interval with an overhead catenary crossover? OTOH, maybe having a single wire set over the right hand lane will eliminate those annoying LLB truckers.  :spin:

Dirt Roads:

--- Quote from: kalvado on December 01, 2021, 04:41:53 PM ---On a serious note, overhead wires limit vertical clearance for oversized cargo in a very unforgiving way.  That may be another thing to think about.

--- End quote ---


--- Quote from: Rick Powell on December 27, 2021, 03:55:17 PM ---And the fact that trolley buses can keep their trolley poles or pantographs engaged fairly easily going 25-30 mph and driving carefully, but a caravan of trucks going 70 mph may not be that easy to do...and how could you switch lanes on a multi-lane highway, except at an interval with an overhead catenary crossover? OTOH, maybe having a single wire set over the right hand lane will eliminate those annoying LLB truckers.  :spin:

--- End quote ---

There's no technical reason that trolley buses cannot operate at higher speeds using a pantograph.  The pantograph does need to be designed for the wear-and-tear associated with higher speeds (ergo, more round trips per hour equates to more wear).  Trolley poles are a whole different story.

The catenary-powered trucks that are being tested in Europe are diesel-hybrid.  To change lanes, they must drop their catenary to engage the diesel engine.  I'm not sure, but I suspect that they employ diesel-electric gensets that continue to supply power to the electric motors.  However, there is no reason that direct-drive can't be used just like hybrid cars here in the United States.  California is studying a version that would use CNG (compressed natural gas) engines for operations off of the trolley wire. 

Battery technology can also be used as the hybrid energy source.  In the trolley-bus industry, there was a push some 15 years ago to develop a battery backup to bridge the gap between sections of trolley wire.  This technology is now used in the LRT world.  Charlotte CATS recently purchased battery-hybrid LRVs to run off-the-grid in the Uptown section so as to avoid installing catenary in the skyscraper zone.  That's exactly backwards of how this technology was envisioned.

There are some complications of any hybrid power system when using controllers to smooth out the changeover from one power source to another.  The mechanical solution of a direct drive engine eliminates an expensive onboard electrical system.

kalvado:

--- Quote from: Dirt Roads on December 28, 2021, 08:09:30 AM ---
--- Quote from: kalvado on December 01, 2021, 04:41:53 PM ---On a serious note, overhead wires limit vertical clearance for oversized cargo in a very unforgiving way.  That may be another thing to think about.

--- End quote ---


--- Quote from: Rick Powell on December 27, 2021, 03:55:17 PM ---And the fact that trolley buses can keep their trolley poles or pantographs engaged fairly easily going 25-30 mph and driving carefully, but a caravan of trucks going 70 mph may not be that easy to do...and how could you switch lanes on a multi-lane highway, except at an interval with an overhead catenary crossover? OTOH, maybe having a single wire set over the right hand lane will eliminate those annoying LLB truckers.  :spin:

--- End quote ---

There's no technical reason that trolley buses cannot operate at higher speeds using a pantograph.  The pantograph does need to be designed for the wear-and-tear associated with higher speeds (ergo, more round trips per hour equates to more wear).  Trolley poles are a whole different story.

The catenary-powered trucks that are being tested in Europe are diesel-hybrid.  To change lanes, they must drop their catenary to engage the diesel engine.  I'm not sure, but I suspect that they employ diesel-electric gensets that continue to supply power to the electric motors.  However, there is no reason that direct-drive can't be used just like hybrid cars here in the United States.  California is studying a version that would use CNG (compressed natural gas) engines for operations off of the trolley wire. 

Battery technology can also be used as the hybrid energy source.  In the trolley-bus industry, there was a push some 15 years ago to develop a battery backup to bridge the gap between sections of trolley wire.  This technology is now used in the LRT world.  Charlotte CATS recently purchased battery-hybrid LRVs to run off-the-grid in the Uptown section so as to avoid installing catenary in the skyscraper zone.  That's exactly backwards of how this technology was envisioned.

There are some complications of any hybrid power system when using controllers to smooth out the changeover from one power source to another.  The mechanical solution of a direct drive engine eliminates an expensive onboard electrical system.

--- End quote ---
Well, I read about electric buses doing 60+ MPH, and Acela can do 150. I don't see speed as a show-stopper once there is some demand  (and actual money to back that up).
California grid issues are a completely different story, though.

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