I’ve always been impressed how efficient el prop is, but what Siemens is up to http://reviews.cnet.com/8301-13746_7-57430211-48/siemens-electrifies-trucks-with-trolley-technology/ is just a bit strange. It would be interesting to hear/read by what means they intend to produce the electrical power.
The panto setup looks a bit strange, too.
Perhaps I’m being too obvious, but what happens when the driver has to swerve to avoid a cow or a deer? Then you have a dewirement or some kind of bigger mess. I just don’t think this technology works all that well for steerable vehicles. Trackless trolleys had a limited amount of success, but has anyone really thought about the sudden loss of power from having to do an avoidance swerve? It appears that there is some kind of battery backup, but how quickly can it compensate for a sudden loss of power? I really doubt that German wildlife is any more predictable than our North American critters.
And yeah, HJ, those pants look a bit unwieldy as well.
Just my $0.02,
David Meashey
Downtown Seattle used to have electric buses that ran from catenary. I always wondered
how the driver kept contact going around corners and such.
We have them all over the place in the towns around Boston, and they seem to do just fine with traffic.
I remember those trolley buses. The trolleys could swing through 360 degrees, if memory serves. I think they used the same catenary that the rail trolley cars used. I can remember seeing some rail cars coming by followed by the buses a few minutes later, on another route.
Los Angeles had trolley buses all through the downtown area. I remember this being in the late forties to mid-fifties. We even had the old traffic signals with the wig-wag blade that came out to show stop and go. They had lights with the blades also. 
Vancouver, B.C. has lots of electric buses running off of overhead trolley wires. Run all the time and don’t seem to have much trouble.
Okay, not trying to argue, but this needs to be pointed out. Trackless trolleys are, for the most part, driven within the confines of a city and at relatively low speeds. There the system works very well. What Siemens is developing is for inter city travel, not intra city travel, and I suppose for at least 55mph and higher. My concern for this system is: What happens the first time a cow amples into the lane, or a deer bounds in front of the vehicle? We all know that this WILL happen. It’s just a matter of when. A driver will naturally react by swerving to avoid impact. Then those pantographs on the vehicle will be leaving contact with the wires. Can the battery backup take over fast enough for safe control of the vehicle?
When I worked as a technical writer for Mack Trucke, Inc., the company had a brief flirtation with the Allison gas turbine engine. One day the turbine burned out while the truck was being driven on a public highway. It happened so fast that the driver barely had time to get to the side of the road before his machine locked up. That’s why I am expressing concern about what happens after a dewirement. You gots a big machine that does not like to stop quickly, and it is on the loose on a public road.
Again, not trying to argue, but it does concern me,
David Meashey
Much like the new “E-assist” vehicles on the road today I would imagine you would have some battery back-up and with the wheels rolling engine start-up would be near instantaneous. Really no more dangerous than being behind a big rig doing 75mph when their rear brakes lock up. Been there, it’s exciting!
My concern is more over the high voltage lines strung over the highway. What happens when they snap and are lying in the road? Or as the truck accidentally departs the lane and the pantograph pops up and snags the line as the driver corrects his position.
Still a great idea though.
Mark;
Good point about the severed wires. Also, The catenary would need to be strung high enough to to clear anticipated oversized loads. I’m not as familiar with the E-assist vehicles, but your explanation makes sense.
I just hope that Siemens’ engineers are also considering these potential problems.
The reason why we see most US electric locomotives running off the rear pantograph (when there are two), is to prevent catenary cable from plunging into the occupied cab, should the pantograph sever the cable.
Best,
David Meashey
That cnet report left the impression that this was in lieu of Diesel trucks. Personally I think it’s a silly idea, if they really want to string wire then they could convert some of the densest traffic rail lines to run under cat. That would result in more efficiencies than umpteen trucks under wire.
BTW the backup in the scheme, when coming off wire, is a diesel driven generator.
They’re projecting pilot projects in LA and Long Beach, and you’re worried about high speeds??? 
Interesting concept, but somehow I don’t see overhead wires being strung down I-95 anytime soon. Easier to string wire along all the railroads and convert them to straight electric, and we all know how likely that is to happen.
Later,
K
It boils down to economics. Can there be money made off the huge investment providing the power ?
Can the trucking companies save money after investing in the trucks ?
If the answer is no to either question, then it will not happen unless the goverment forces the issue.
Ralph
As much as I like the idea from a purely environmental/engineering viewpoint, I’d much rather the Fed subsidize the electrification of the major rail lines. There were two major reasons PRR never completed electrification west of Harrisburg/Enola. Obviously the first was money, but the second part was the lack of an electric locomotive capable of performing helper service over horseshoe curve. With our use of SD-40’s today, there isn’t any reason we couldn’t develop a dual powersupply SD-40 capable of drawing power from overhead wires.
The alternative to pantographs/catenary is a very long trailing power cord like an electric lawn-mower… ;=/
In the rural environment that’s about as practical as it will ever get.
I’m not being a luddite, but unless and until they can produce a hydrogen-powered truck, a whole lot of euros are being wasted on already-proven-not-to-be-viable propulsion here.
This, friends, is the equivalent of developing a carbon-fibre and titanium buggy-whip.
tac, ig & The Great Nebraska Alpine Chorus Boys
tac said:True, but you can get gummint grants to develop a carbon-fibre and titanium buggy-whip, and then file for bankruptcy when the money runs out. :P
This, friends, is the equivalent of developing a carbon-fibre and titanium buggy-whip.
tac,
Out Vancouver way we have Ballard Power Systems, they had been at the automotive end of hydrogen fuel cells for quite a while, but then sold out that segment of development to Daimler and Ford. http://en.wikipedia.org/wiki/Ballard_Power_Systems
Would be interesting to find out the nitty gritty of reasoning behind selling that to the automotive industry, eh!?!?