Interesting use for battery-electric units.
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While itâs an impressive system, Iâm not sure I believe all the claims of no outside electricity needed.
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Given the recent news about highly efficient traction motors and large-capacity storage batteries, it seems that such a system is possible.
âOh ye seekers after perpetual motion, how many vain chimeras have you pursued? Go and take your place with the alchemists.â
â Leonardo da Vinci, 1494
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This is no more perpetual motion than a dumbwaiter is.
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The problem is between the headline and the actual workings of the train.
The headline says it never needs outside energy.
The article states, "That energy is enough to bring the unloaded train back to the mine, eliminating the need for external charging infrastructure or additional renewable energy sources, making the train almost entirely self-sufficient.
I bolded the words. Thereâs an issue between âneverâ and âalmostâ.
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You, me, and the fellow who would be behind the tree (if the surface-of-Mercury Pilbara had any trees) know net-zero rhetoric when we see it. Of course theyâre not going to operate without a few breakdowns or other issues requiring relief trains, and of course they will have multiple recharge points and mobile rechargers for general operation if they lose their minds and actually convert fully to battery-electric.
The principle remains interesting and, in theory, the numbers actually work in this special case.
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Electric railways in urban areas, which operate frequently, are steadily reducing their power consumption thanks to the effects of regenerative braking. Lighting and air conditioning are also becoming more energy efficient. Intercity high-speed railways are no exception.
The only thing that has struggled with exhaust gas regulations is heavy-duty freight railroads, but in the near future we will likely see a breakthrough in the form of hydrogen engines and the like.
A key to this in practice, where traffic is not so dense that reverberation is balanced by acceleration, is to provide âwayside powerâ, which has been a topic of interest for decades (it was nominally the subject for a whole volume of reporting in the Garrett dual-mode-lite study from the late '70s). This stores the regenerative-braking current, and then provides it again as the brakes vehicle re-accelerates. This has been one of the âfirst best applicationsâ for flywheel KERS. We of course thought magnetic storage would be a âkiller technologyâ in the late '90s.
This system puts the regenerative storage entirely onboard, as there are no immediate plans to string wire. It will not have escaped wise readers that punctuated electrification will work perfectly to provide the emergency charge stations I referred to earlier, and perhaps persistent wayside storage would be used for these if there is no easy grid-AC access or desire for emergency generators at those sites.
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Reminds me of the proposed âStaley Systemâ where a proposed electrified line from the coal mines in Colorado to the Gulf of California was supposed to generate more electricity from regenerative braking than what would used to haul the empties back up to the mines.
I agree with W_H in that there better be some provision for recharging to accommodate adverse headwinds for the empties and other issues.
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Perpetual motion machines rarely work.
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Some of them work just fine⌠but not for very long. Others are great as long as the batteries under the table hold out.
Incidentally, current in a superconductor is effectively a perpetual-motion machine. The problem is that itâs âoverunityâ thatâs forbidden, so as soon as you want the thing to do any extractable work⌠it will slow or stop.
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Itâs not a perpetual motion machine. The down trip with the ore loads puts extra energy into the system which is captured by the regenerative brakes. The trip back with the empty ore cars uses that stored energy.
The intent is - with the captured regenerative energy - there are losses in generating the regenerative energy, there are losses in storing the regenerated energy and there are losses in distributing the regenerative energy. The accumulative losses will require additional energy to be injected into the system.
That I am aware of, both MILW and GN attempted to use the regenerative energy of down grade Electrically powered trains to assist other trains operating upgrade. How well that system worked is open to question as both carriers ended their electrical operations when the time came for renewed investment into their electrical operations to continue their operation.
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You miss the entire point of the idea.
The loaded train is running downhill to tidewater. I do not have exact figures on what the average load of one of these Pilbara trains is, but it is loaded with a LOT of iron ore, which contributes its weight to the regenerative braking. 22,000 tons or more is going to produce a considerable amount of dynamic KWh, and we assume that enough battery/supercap capacity is provided to store it all without exceeding ~80% battery capacity in normal service (to maximize cycle life at rated capacity.)
Now at tidewater, the train is emptied of that 22,000t or whatever (the energy used to dump and bulk-load not being provided by the battery-electrics, so from an energy standpoint emptied for free. Take the tare weight of the empty lightweight hoppers or gons, and calculate the KWh to lift that empty train back up to the mine.
Even with all the anticipated losses, you can see that this cycle develops far more from the sum of all the downgrade trips than it uses (and loses) going back upgrade. Another way to think of it is that the downhill trips are turning electrical generators using the gravitational potential energy of many thousands of tons of heavy ore, over and over, as fast as the unit trains can be turned.
In theory the Pilbara is a nifty place for solar renewable generation⌠too good in some respects, if you catch my drift. The economics work out âbetterâ if you use renewable energy for some of the uphill power, once youâve amortized all the stranded cost involved. In the meantime I expect a couple of C175 or QSK gensets on the equivalent of Brandt units is all that would be required to âprotectâ the basic zero-carbon cycle as described.
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The theory is fine - the devil is in reality.
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Spoken (um written) like someone with way too much experience with reality not following theory.
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I understand the idea and it is compelling, but I think people forget that what Wabtec/GE and Progress Rail/EMD really bring to the table with their diesel locomotive designs is demonstrated reliability under the most arduous operating conditions. I have never heard of the company that has assisted Fortescue with building this battery electric locomotive from a nearly 30 year old C44-9W. It might work out great, or it might be another genset debacle. The curious thing is that the Roy Hill operation ordered a similar Wabtec FLXDrive loco only to cancel the order after the unit was built. And I canât find any updates on the FLXDrive units that UP and CN ordered a few years back.
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The Downer Group has lots of experience in locomotive design and building. Downer took over Clyde Engineering which e.g. designed and built the Australian Downer EDI Rail GT46C or Downer EDI Rail GT46C ACe using EMD components.
The batteries are best integrated by their manufacturer.
There is a video that shows a pantograph:
https://www.youtube.com/watch?v=6CRy7-fyAjc&t=78s
The concept can work depending on the energy balance as W_H described. And a back-up is a good idea in case something goes wrong or the locomotive is operated on a route were the energy balance doesnât work in favor of the locomotive.
Regards, Volker
Thanks for the info on the connection with Clyde Engineering. Iâm still skeptical about the day-in day-out reliability of an all battery locomotive in heavy-haul mainline service until thereâs an availability track record to evaluate.