h a l f b a k e r yContrary to popular belief
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Many railway lines rely on locomotives burning fossil fuels, mainly diesel.
Electrical traction has many advantages, as the power source is remote and stationary, and therefore many efficiency-improving and pollution reducing measures can be incorporated, not possible in a mobile system.
However,
transmission to the power car of a train requires either an overhead line and pantograph, or a third rail - notoriously dangerous.
We propose a system which will have the advantages of electrical traction and can be employed in mountainous areas, reducing damage to lines by snow, ice and wind, and the need for maintainance and repair.
The power car has mounted on its roof a "power receiver". This is a parabolic dish, made of refractory material, backed by a jacket of liquid, the "working fluid", which is a closed system. A servo system is capable of maitaining the "aim" of the dish with great accuracy, despite the movements of the power car below it.
At intervals, on the tops of hills, are steel latticework towers, on the top of which is a high power laser, emission frequency to be chosen by the design team. If it were possible to use a visible frequency, this would produce an attractive light show whenever a train passed by.
This laser can be trained by a servo system analogous to the one on the power car, but with the advantage that the tower is relatively stiff and does not move.
Local windfarms could be used to feed power into the system.
A substantial electrical supply is delivered to the control building forming the base of each tower.
When a power car approches within the service area of the tower, the laser automatically aims round towards the receiver, which also aims itself otward the tower. When a lock has been established, the laser turns on. The reciever becmes very hot, and the heat is transferred by the working fluid to a turbine system and then directly to the wheels, or via an turbine/electric/notor system. "Waste" heat is used for heating the carriages if required. Surplus low-grade heat is then dumped by conventional radiatiors.
The laser tracks the power car until it reaches the limits of the service area, at which point it "hands over " to the next "cell".
An onboard power storage system is included to cope with tunnels which might cause obscuration of the beam for more than a few seconds.
This system has the advantage that only one train can move on one track at a time, reducing the possibility of collisions. Dual track systems would have pairs of lasers, one for the up-line, one for the down.
Power Beaming Competition
http://www.spacewar...levator2010-pb.html
[MisterQED, Jan 19 2008]
[link]
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I can see this being fine in places like the Valleys in Wales, but then there's somewhat flatter places. Also I can see trains being delayed due to fog... |
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Wait a mo. You want to put megawatt-class lasers in the hands of the UK railway franchises? You nearly earn a bone just for that. [+] because this just may be the epitome of a halfbaked idea. |
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It's intended as a solution in less accessible (mountainous) locations - on flat terrain, it's easy to construct and maintain a perfectly satisfactory overhead line. |
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Flocks of birds make for a jerky ride. |
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Reduces the pigeon count, though. |
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No, the buffering effect and thermal inertia of the turbine system would smooth out the jolts caused by the occasional incinerated avian. |
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The transmission part of this is attempting to be baked in the "Power Beaming Competition", see link, so I understand this in certain situations, but think there will be significant power losses in laser creation. From what I have read, for power beaming they have leaned towards microwave lasers but as you said "emission frequency is up to the design team". I also think the transmission is less efficient than electrical for short distances, so best in places like Wyoming, but useless in NJ where line of sight is severely limited. But many locations will have some problems with birds, trees, fog other mountains and buildings. |
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And you subtitle is a bit inaccurate, "avoid the complexities of electrification". The complexities of electrification will be simple in comparison to the complexities of twin tracking systems to connect a moving vehicle to a tower without cooking a passenger who is only 20 feet away from one of the receivers looking out a window. |
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Mirror glass in the windows ? |
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// birds, trees, fog other mountains and buildings. // |
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Birds and trees will not represent a problem. With a continuous beam power of half a megawatt, the beam path is "self-cleaning". And at that power, it will go straight through fog (=> steam), maybe with a little scattering. Since the towers are placed high up, buildings shouldn't be an issue, but a neat spinoff is the instant and ruthless enforcement of any planning regulations concerning high-rise buildings. |
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I've often wondered, why not laser steam engines? |
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//fog (= steam), //
water vapour != steam |
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The point was that the laser would rapidly convert the condensed fog droplets to steam (which is invisible). |
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Amended to try to represent phase change. |
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//the laser would rapidly convert the condensed fog droplets to steam //
A maser might, but I'm not sure about a visible light laser, still less an IR laser. |
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Think of all the fun vandals could have with mirrors, too. |
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"Right children - now everybody put
down their skipping ropes and stand
behind me. Today, we're going to be a
train. George, Amygdala, Adenine -
you three are going to be the
locomotive, so get your arms moving
and make lots of lovely chuffing
noises...are we ready? And.....off we
go!" |
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<in the distance, sophisticated
electronics detect the characteristic
signals and stir into action> |
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