As I pointed out before, DDOT has no plan to avoid using overhead lines to power streetcars. I have blogged about onboard vehicular power storage, namely supercapacitors and batteries. I engaged in some dialogue about this on Greater Greater Washington. I have done a little research and found yet another method to store power: flywheel power storage. An English company, Parry People Movers Ltd., has been doing work on this. They even have implemented a diesel prototype. Its partner, JPM Parry & Associates claims to be designing a 220-passenger light rail vehicle, in a multiyear effort. While electrical power is a possible source, neither website has information about how long a vehicle could run on it.
A possible compromise position for DC streetcars is to use electrical power storage with charging umbrellas and a diesel or turbine engine. This is an engineering task. DDOT does have engineers, doesn't it?
Showing posts with label light rail. Show all posts
Showing posts with label light rail. Show all posts
Friday, December 5, 2008
Wednesday, November 12, 2008
Anacostia Light Rail: A Solution in Search of a Problem
DDOT initially conceived the Anacostia light rail as a starter system for a network of light rail lines throughout DC. Anacostia was chosen to be first as it would be connected to the rail yard and be relatively inexpensive to build. This was contingent on obtaining CSX's right-of-way to build a (relatively) high-speed connection through Anacostia between the Anacostia and Minnesota Ave. stations. The deal fell through, so DDOT is now reduced to trying to build a light rail line in Anacostia to, well, perhaps show that it can be done. As Greater Greater Washington has pointed out, the latest incarnation will continue an all-too-short (and low speed) distance on Anacostia's streets and maybe will be extended to the 11th St. Bridge. After that, there is simply no plan.
DDOT also assumed away the problem of the ban on overhead wires. Not every light rail line can go on abandoned railroad tracks. In fact, one of the illustrations shows overhead lines on a street. Let's face it, the overhead line ban is not going away. Moreover, given improvements in power storage technology, it may be possible to avoid them completely by having quick charges from short overhead lines integrated into stations.
So, DDOT has to go back to the drawing board. First, it has to find a way to get the CSX right-of-way. Eminent domain is a possibility that hasn't been tried. This may be difficult, as railroads are generally accorded strong property rights. You can't do a lot of things to railroads that you can do to other properties. Still, the line is abandoned, which is the argument that DC will have to use. Second, DC has to solve the overhead wire problem. By doing so, it can reduce construction costs and set an example for other cities to emulate. The Anacostia LRT can be used as a test bed.
DDOT also assumed away the problem of the ban on overhead wires. Not every light rail line can go on abandoned railroad tracks. In fact, one of the illustrations shows overhead lines on a street. Let's face it, the overhead line ban is not going away. Moreover, given improvements in power storage technology, it may be possible to avoid them completely by having quick charges from short overhead lines integrated into stations.
So, DDOT has to go back to the drawing board. First, it has to find a way to get the CSX right-of-way. Eminent domain is a possibility that hasn't been tried. This may be difficult, as railroads are generally accorded strong property rights. You can't do a lot of things to railroads that you can do to other properties. Still, the line is abandoned, which is the argument that DC will have to use. Second, DC has to solve the overhead wire problem. By doing so, it can reduce construction costs and set an example for other cities to emulate. The Anacostia LRT can be used as a test bed.
Friday, August 1, 2008
LRVs Without Overhead Wires?
Bombardier's "MITRAC Energy Saver" consists of an supercapacitor bank and associated electronic. Its primary use is to recover energy from braking, but Bombardier claims that 1 km of acceleration is possible.
The weakness of this technology is its low voltage. According to the product information, it runs at 750 volts. To get, say, 10 km of acceleration, the voltage has to increase to 7,500 volts. It is unclear from Bombadier's website how much charge is stored. Still, the supercapacitors have to have about 10 times greater voltage, or be 1/10th of the size of the current ones to store this much charge.
Thus, we can conclude that this technology is unripe.
So, what does this have to do with anything? I've been following the talk about light rail lines in Washington, DC. It seems that the Congress has long forbidden overhead wires on streets. Getting power from a third rail using either the old conduit track technology or the new technology in Bordeaux is impractical. So, the way to get streetcars running is to charge them at stations. Right now, this appears impractical. But, improvements in battery and supercapacitor technologies may make this feasible within 5 years. So, all of you who like to dream up light rail systems should think in terms of having chargers at terminals and stations, with Shanghai-like charging "umbrellas".
The weakness of this technology is its low voltage. According to the product information, it runs at 750 volts. To get, say, 10 km of acceleration, the voltage has to increase to 7,500 volts. It is unclear from Bombadier's website how much charge is stored. Still, the supercapacitors have to have about 10 times greater voltage, or be 1/10th of the size of the current ones to store this much charge.
Thus, we can conclude that this technology is unripe.
So, what does this have to do with anything? I've been following the talk about light rail lines in Washington, DC. It seems that the Congress has long forbidden overhead wires on streets. Getting power from a third rail using either the old conduit track technology or the new technology in Bordeaux is impractical. So, the way to get streetcars running is to charge them at stations. Right now, this appears impractical. But, improvements in battery and supercapacitor technologies may make this feasible within 5 years. So, all of you who like to dream up light rail systems should think in terms of having chargers at terminals and stations, with Shanghai-like charging "umbrellas".
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