The innovative principle of the PRIMOVE system is rooted in the principle of inductive power transfer, a technology used in cleanrooms in the computer chip and automotive industries. With Bombardier's introduction of PRIMOVE, inductive power transfer comes to rail vehicles for the first time.Apparently they have been testing in Germany since 2003 and the system apparently can work in all weather, unlike the Alstom APS system which reportedly has problems with ice and snow. Now we wait for commercial installation and testing under real life conditions. I'm cautiously optimistic.
Thursday, January 22, 2009
The Overhead Wire is Done
No not me or the blog, rather the wires that bring electricity to streetcars and light rail. Yonah brings our attention to an MSNBC article in which Bombardier unveils their new technology advancement.
Subscribe to:
Post Comments (Atom)
19 comments:
Seems like an interesting solution to the overhead wire problem in cities. I honestly think this is a much better (and safer) way to go than APS. I don't think overhead wires are going away anytime soon though: they're just too efficient in most cases, and can be made relatively unobtrusive in cities by bolting the span wires directly to buildings, and using a relatively light gauge wire.
I wonder how efficient the power transfer will be, given the spacing between the "transmitter" and the "receiver" (or "primary" and "secondary", to use transformer terminology).
You're way behind the curve here - I plugged this in a comment on CAHSR Blog weeks ago.
As much as I try to read every comment from the 500 blogs and news sources I get information from every day it can be a little daunting Alon :) Thanks for letting me know I'm behind the curve though. I'll try and catch up.
Actually, you are all WAY behind. This has been in the works for years now. Ground level power systems have been in use since 2003. That being said, how will this work in cities where there is significant snowfall?
Obviously this has been in development for some time - you don't just talk about this stream of consciousness - but Bombardier's press release just went out today. Let's cut TOW a little slack. This is relevant news.
"Since 2003" refers to when APS has been used in Bordeaux. I did have some skepticism about APS when I heard of its use there. It was like thinking, "Huh?"
NIMBY's attempt to use "overhead wire" excuse all the time, yet they don't seem to mind the mass of telephone and cable wires that blights most American cites. Funny, that.
I personally like overhead wires. It adds to the landscape.
Without wires, those pushing for trolley buses will now be no different than other streetcar opponents saying it's not worth the cost. And ironically, wireless streetcars do look more like "buses on rails," as their opponents like to call them.
count me in as a fan of overhead wires (and The Overhead Wire too).
Will be great for electric cars. Could charge on freeways and at lights. Now trams have no advantage over buses and cars.
(I think overhead wires actually make environments more human by providing an implied ceiling - psychologically significant)
Yes, this sort of thing might work for electric cars on freeways too, although obviously it requires a huge amount of infrastructure investment. But it would make an all-electric car system feasible. However, trams and trains still have an advantage, since steel on steel is still much more energy efficient than rubber on road, and the ability to form trains gives it even more of an advantage.
I know I'm a few days late commenting here but I had to say something.
I'm not sure if I like this idea or not. I know some people really think of LRL wires as an eyesore (despite the fact that they ignore the wires caused by telephone poles and streetlights). But still, it does counteract against the argument of LRLs being an eyesore.
I would also suspect there's some level of energy loss caused by this 'contactless' transfer of energy. How much energy do you lose when you convert it to a magnetic field and then back into actual electricity. Also, I know they say this would mean less strain and cost of maintaining wires and parts, etc. but really, wouldn't one think that these PRIMOVE things are terribly expensive to install and maintain?
And I have to agree that light rail wires are actually somewhat attractive (depending on how they are set up). For example, I've been on the Tampa TECO line in Florida, and I have to say it looks fairly nice and actually adds a touch to the city. The new Marseille, France LRT wires look fairly nice too. I've also been on the Houston LRT system which I have to say is not attractive at all. Whether LRL wires make a significant change in a 'psychological ceiling' or if that would improve the quality of life in any way, I would not know unless somewhat can cite some research that says so.
As for using this for cars and highways, I would have to say that's near impossible. On an LRL, you have a strict right of way which means the environment for controlling these underground magnetic fields is fairly easy. With roadways, not only do you have significantly more square feet of ROW per capita, you also have to remember that automobiles are more liberal in their movement and somewhat unorganized so you can't guarantee that a car would follow an exact path for so many miles. They meander and make turns, switch lanes, turn around etc. We would have to cover every square inch of asphalt with this thing versus a single path for a LRL. And you would have to cover every interstate, highway, road, street, parking lot, and driveway in America. Given the excessive area that roads take up per capita, that's not anywhere near close to feasible.
Interestingly, my father (who is in the bus business right now) is considering entering LRT.
Using this for cars runs into the same fantasy as electric cars themselves: it just doesn't scale well.
Anyway, as for wires, I find them a pleasing route marker. Except some of the more modern implementations are truly ugly, like the one in Buffalo, where for some reason the whole setup is much bulkier than would seem necessary (i.e. there are 2 wires, one above the other, and all sorts of extra wiring to connect them--I don't know the technology at all, but it seemed like overkill to me, when I lived there.)
Back in the 1980's there was a publication called "Traction Yearbook", which would chronicle the year's developments in the light rail field. The author/publisher had a crusade going against "overbuilt overhead"; as I recall he printed a photo of one super-sturdy overhead installation with a comment something like, "Were they planning to run GG-1's?" I think the SEPTA structures in Upper Darby (near the former Red Arrow terminal) drew some fire, and Pittsburgh may have also been rapped. He maintained that unnecessarily heavy overhead defeated the purpose of light rail, which is to provide electric rail transportation with a minimum of cost. It's like some of the engineers who design these systems get paid by the ton (of steel that the project buys). I haven't checked that closely, but how many new installations use eyebolts in adjacent buildings (when in downtown areas), rather than installing massive supports?
I wasn't serious about cars. The power transfer of a magnetic field (modulo the recent discovery of long distance resonant transformers) through air drops with the cube of the gap, and the low permeability of air means that you get very poor coupling. I doubt the efficiency of this is more than 50%. To maximise the efficiency the core needs to be very close to the coil. In a car the gap needs to be much greater to handle the rough surface and jostling. And given how well maintained most road surfaces are in the US, I doubt the system would last a week :) A huge advantage rails have is the fact that you know exactly where the load is placed, allowing everywhere else to be completely un-load-bearing (grass!)
On this point, any idea why grassed tracks aren't(AFAIK) used in the US? Here in SJ I can imagine that the low rainfall might make sedums more likely, but the point remains.
I agree about light rail being overbuilt - much of Melbourne's network is just built with cable support from buildings, with a single conductor. I expect this doesn't work so well at high speed, but within built up areas this isn't a problem.
I wonder if there is any possibility of cross-over design from maglev and linear motor systems. Perhaps once out of town the wheels fold flat and the train heads out with a passive maglev and linear motor. (a bit SF I know :)
Once out of town, the motorman cuts in the field shunts. This system doesn't require the conductors to land a trolleypole on the wire on the fly, either.
The discussion of overbuilt overheads on light rail lines is some 20 years old at least. Pittsburgh's rebuilt southwest side lines are the case I'm most familiar with. The catenary structure is excessive: compare the British West Coast Main Line, or look up pictures of the North Shore Line in Wisconsin.
This is really intriguing for rapid streetcars - aka tram-trains - as one problem of electrifying shared rail corridors is of overpasses, underpasses, tunnels etc. that are built to a loading gage that does not have an allowance for overhead catenary.
Of course, the scope for tram-trains under the FRA is less than in Europe.
Post a Comment