IMO some of our posters are making a mountain out of a mole hill concerning low clearances. If a lower clearance is a problem just lower the voltage thru the low clearance area(s). The use of tap changing transformers is well known. Later models of tap changers are automatic such as Acelas, Sprinters, AEMs with some older units such as E-60s, EMUs & etc either automatic or manual.
So, 25 kV is not required everywhere. Can be 12.5, 6.25, 3.12 or some other voltasge. The AAR would need to desiginate whatever voltages. Read somewhere that some location in Europe uses ~3 kV in a constrained location. Even CSX's Virginia Ave tunnel will be able to use some lower voltage.
Another method would be to operate all trains thru a low clearance area to have an electric motor in front and one at rear of train operating in DPU. Just run CAT as an isolated dead section under low clearances allowing unpowered units to coast thru dead section with other unit(s) providing traction for train movement.
blue streak 1 MidlandMike It's not all gravy once the electrification is built. The NEC was built around a century ago, and needs tens of billion$ just to bring it to a state of good repair. Have you checked what all that money is about? Maybe $1 - 2B for all the CAT work. All the rest is ROW, Sawtooth bridge Dock bridge. bridges including the Maryland and Connecticut bridges. Undercutting the whole track to remove bad sub grade, stations, & Etc.
MidlandMike It's not all gravy once the electrification is built. The NEC was built around a century ago, and needs tens of billion$ just to bring it to a state of good repair.
Have you checked what all that money is about? Maybe $1 - 2B for all the CAT work. All the rest is ROW, Sawtooth bridge Dock bridge. bridges including the Maryland and Connecticut bridges. Undercutting the whole track to remove bad sub grade, stations, & Etc.
I would love to see the numbers, can you provide them? If the cat work is only an inconsequencial amount, then why are you always reporting on cat problems on the NEC?
MidlandMike I would love to see the numbers, can you provide them? If the cat work is only an inconsequencial amount, then why are you always reporting on cat problems on the NEC?
Just a reminder for those who say to use DP and have some of the power "coast" while going through a tunnel. Many tunnels are used to get rid of the top of a grade so it really wouldn't work to cut off the power of some of the locomotives.
BackshopMany tunnels are used to get rid of the top of a grade so it really wouldn't work to cut off the power of some of the locomotives.
The point about varying catenary voltage with overhead clearance ignores the increased current (and hence various I2R losses) inherent in using a lower voltage in traction applications. A much better use would be in conjunction with battery dual-mode-lite hybrid power, where 'every little bit' of charging power could be helpful without compromising the performance of the train through 'restricted clearance' areas.
blue streak 1Because it is an outdated type of construction. 1. Steel poles directly into the ground slowly rusting away. ...
The photo I see of a standard PRR cat section shows the poles (I-beams) on a cement foundation, although I can't tell if they are bolted to the foundation, or sunk into the cement. I know the PRR cat is basically obsolete, but my point is that if congress does not fund replacement of their own problem plagued cat, then what is the likelyhood of them funding widespread freight line electrification.
The logical solution is low-voltage same AC 60Hz frequebcr 3rd rail just though the restricted-clearance area and possibly 500 feet overlap transition lengrth each side.
If memory is correct, each concrete base was port with steel set into the top that looked like a flat bplate, but pobably had "feet" extendibg into the concrete, and the line poles were bolted to attachments intagral with each plate. Should be a drawing somewhere.
Pretty much the same PRR and NYNH&H.
daveklepper The logical solution is low-voltage same AC 60Hz frequebcr 3rd rail just though the restricted-clearance area and possibly 500 feet overlap transition lengrth each side.
One issue with 60Hz and 3rd rail is that the 60Hz impedance of rails is at least 6 times higher than the DC resistance. One option is copying BART with aluminum bonded to the sides of the 3rd rail. The other option is using DC on the 3rd rail and using a DC-DC converter for converting 3rd rail potential to the DC-link potential of the traction inverters. This converter would be smaller and lighter than the transformer.
Batteries have the advantage of providing power though spots where the catenary may be out of service due to maintenance and also though areas where it is not economical to electrify. Battery technology has come a long ways from when the CNS&M, DL&W and the NYC were using electric locomotives with batteries. I would also think the LFP batteries would be a better fit than Li-ion.
The 'correct' solution for track-level electrical contact is going to be 'smart third rail' (which is basically an upgrade of the old GE idea of having contacts raised and actuated as a shoe under the locomotive contacts them). There are in particular some Japanese and Italian versions that have near-continuous contacts embedded in a polymer structure, actuated electronically. As Eric notes, these are best implemented with DC / running-rail return, but the transversion from AC can be done nearly at each point of contact. I would of course argue for ~1500VDC fed via suitable equipment to the DC-Link of connected dual-mode-lite hybrid consists. (Adding the necessary 'connectivity' to one of Iden's "tenders" would not be technically difficult either...)
There are few reasons, though, not to build the bulk of the electrification as overhead constant-tension line with the usual wear-reducing lateral sinusoid pulloff, and keep any return-current arrangements in the rails compliant with that.
Overmod The 'correct' solution for track-level electrical contact is going to be 'smart third rail' (which is basically an upgrade of the old GE idea of having contacts raised and actuated as a shoe under the locomotive contacts them). There are in particular some Japanese and Italian versions that have near-continuous contacts embedded in a polymer structure, actuated electronically. As Eric notes, these are best implemented with DC / running-rail return, but the transversion from AC can be done nearly at each point of contact. I would of course argue for ~1500VDC fed via suitable equipment to the DC-Link of connected dual-mode-lite hybrid consists. (Adding the necessary 'connectivity' to one of Iden's "tenders" would not be technically difficult either...) There are few reasons, though, not to build the bulk of the electrification as overhead constant-tension line with the usual wear-reducing lateral sinusoid pulloff, and keep any return-current arrangements in the rails compliant with that.
I think both overhead wires and third rails do not have much of a future and sooner or later someone will cross the threshold with a self contained powerplant that will replace the diesel and will be as cheap or cheaper to run and maintain.
Wabtec and it's hybrid Diesel is getting closer but it still has emissions.
CMStPnP Overmod The 'correct' solution for track-level electrical contact is going to be 'smart third rail' (which is basically an upgrade of the old GE idea of having contacts raised and actuated as a shoe under the locomotive contacts them). There are in particular some Japanese and Italian versions that have near-continuous contacts embedded in a polymer structure, actuated electronically. As Eric notes, these are best implemented with DC / running-rail return, but the transversion from AC can be done nearly at each point of contact. I would of course argue for ~1500VDC fed via suitable equipment to the DC-Link of connected dual-mode-lite hybrid consists. (Adding the necessary 'connectivity' to one of Iden's "tenders" would not be technically difficult either...) There are few reasons, though, not to build the bulk of the electrification as overhead constant-tension line with the usual wear-reducing lateral sinusoid pulloff, and keep any return-current arrangements in the rails compliant with that. I think both overhead wires and third rails do not have much of a future and sooner or later someone will cross the threshold with a self contained powerplant that will replace the diesel and will be as cheap or cheaper to run and maintain. Wabtec and it's hybrid Diesel is getting closer but it still has emissions.
EuclidWhat do you mean by, “Self-contained power plant” ?
I'm kinda stumped by this too, because I'm reading some sort of description of an electric locomotive with a "self-contained power plant." Which is....literally what a diesel locomotive is?
NittanyLion Euclid What do you mean by, “Self-contained power plant” ? I'm kinda stumped by this too, because I'm reading some sort of description of an electric locomotive with a "self-contained power plant." Which is....literally what a diesel locomotive is?
Euclid What do you mean by, “Self-contained power plant” ?
I'm guessing a fuel cell.
Jeff
Erik_Mag Batteries have the advantage of providing power though spots where the catenary may be out of service due to maintenance and also though areas where it is not economical to electrify. Battery technology has come a long ways from when the CNS&M, DL&W and the NYC were using electric locomotives with batteries. I would also think the LFP batteries would be a better fit than Li-ion.
Just some back-of-the-envelope numbers to drive home the point. All numbers are derived from Googling, I don't really know that much about locomotives but I know how to Google:
- An ET44AC locomotive is rated for 4400 HP (3,300 kW)
- The GEVO-12 prime mover weighs 42,300 lbs. Its fuel tanks can hold 5,000 gallons of diesel, which weighs around 35,000 lbs.
- If you replace the prime mover and the fuel tanks with a battery, the battery could weigh over 77,000 lbs (35,000 kg) without increasing the total weight.
- LFP batteries have an energy density around 150 wh/kg. So that battery could hold about 5,250 kWh of energy.
- So you could run the locomotive at Notch 8 for about 1.6 hours minutes on a fully charged battery (5,250 kWh / 3,300 kW)
- To maximize battery life you probably don't want to regularly do a full charge and discharge. If you try to keep the battery level between 20% - 80% of capacity, you can run for roughly 0.95 hours minutes at notch 8.
- The longest rail tunnel in the USA is the Cascade Tunnel at 7.8 miles.
- So, if you charge the battery to 80%, run through the Cascade tunnel at notch 8, as long as you can maintain an average speed of 8.2 MPH, then your battery will still have at least 20% left when you emerge. (And the DP unit is less likely to shut down in the tunnel due to excessive heat and poor air!)
You can quibble with lots of details here, but unless I screwed up something pretty major, the point is current battery technology should be more than enough to get you through just about any clearance restriction between Seattle and New York.
Dan
How long would it take and how much money would it take to recharge a battery of that size?
dpeltier Erik_Mag Batteries have the advantage of providing power though spots where the catenary may be out of service due to maintenance and also though areas where it is not economical to electrify. Battery technology has come a long ways from when the CNS&M, DL&W and the NYC were using electric locomotives with batteries. I would also think the LFP batteries would be a better fit than Li-ion. Just some back-of-the-envelope numbers to drive home the point. All numbers are derived from Googling, I don't really know that much about locomotives but I know how to Google: - An ET44AC locomotive is rated for 4400 HP (3,300 kW) - The GEVO-12 prime mover weighs 42,300 lbs. Its fuel tanks can hold 5,000 gallons of diesel, which weighs around 35,000 lbs. - If you replace the prime mover and the fuel tanks with a battery, the battery could weigh over 77,000 lbs (35,000 kg) without increasing the total weight. - LFP batteries have an energy density around 150 wh/kg. So that battery could hold about 5,250 kWh of energy. - So you could run the locomotive at Notch 8 for about 1.6 hours minutes on a fully charged battery (5,250 kWh / 3,300 kW) - To maximize battery life you probably don't want to regularly do a full charge and discharge. If you try to keep the battery level between 20% - 80% of capacity, you can run for roughly 0.95 hours minutes at notch 8. - The longest rail tunnel in the USA is the Cascade Tunnel at 7.8 miles. - So, if you charge the battery to 80%, run through the Cascade tunnel at notch 8, as long as you can maintain an average speed of 8.2 MPH, then your battery will still have at least 20% left when you emerge. (And the DP unit is less likely to shut down in the tunnel due to excessive heat and poor air!) You can quibble with lots of details here, but unless I screwed up something pretty major, the point is current battery technology should be more than enough to get you through just about any clearance restriction between Seattle and New York. Dan
Your calculations may be accruate for that single grade. Line segments are not made up of only a 'single grade' there are many grade permutations both ascending and descending that are involved in traversing the distances between origin and destination. Locomotives have to operate the entire distance of their runs, not just the ruling grade.
Never too old to have a happy childhood!
Self contained power plant that does not use fossil fuel, replacement for diesel, that does not require overhead wire or a third rail. I can't see use of third rail increasing without other requirements like ROW fencing around the third rail. Overhead wire to me seems expensive to install and maintain.
jeffhergertI'm guessing a fuel cell. Jeff
Too expensive to operate unless they bring that part down in price. I think the first trains were Stadler Flirts or something in Germany? Germany has already stated no more of that nonsense and flipped back to electric or diesel. Shortly after that happened, Amtrak thought it would be a great idea to order more of those trainsets for California (lol). You have to give Amtrak some kind of management award for that.
CMStPnPSelf contained power plant that does not use fossil fuel, replacement for diesel, that does not require overhead wire or a third rail. I can't see use of third rail increasing without other requirements like ROW fencing around the third rail. Overhead wire to me seems expensive to install and maintain.
Someone is going to have to invent something, then, as you've ruled out virtually all of the solutions I know of.
Even going electric is likely to still involve fossil fuels.
Larry Resident Microferroequinologist (at least at my house) Everyone goes home; Safety begins with you My Opinion. Standard Disclaimers Apply. No Expiration Date Come ride the rails with me! There's one thing about humility - the moment you think you've got it, you've lost it...
BaltACD dpeltier Erik_Mag Batteries have the advantage of providing power though spots where the catenary may be out of service due to maintenance and also though areas where it is not economical to electrify. Battery technology has come a long ways from when the CNS&M, DL&W and the NYC were using electric locomotives with batteries. I would also think the LFP batteries would be a better fit than Li-ion. You can quibble with lots of details here, but unless I screwed up something pretty major, the point is current battery technology should be more than enough to get you through just about any clearance restriction between Seattle and New York. Your calculations may be accruate for that single grade. Line segments are not made up of only a 'single grade' there are many grade permutations both ascending and descending that are involved in traversing the distances between origin and destination. Locomotives have to operate the entire distance of their runs, not just the ruling grade.
dpeltier Erik_Mag Batteries have the advantage of providing power though spots where the catenary may be out of service due to maintenance and also though areas where it is not economical to electrify. Battery technology has come a long ways from when the CNS&M, DL&W and the NYC were using electric locomotives with batteries. I would also think the LFP batteries would be a better fit than Li-ion. You can quibble with lots of details here, but unless I screwed up something pretty major, the point is current battery technology should be more than enough to get you through just about any clearance restriction between Seattle and New York.
The subject wasn't grades, ruling or otherwise. The subject was clearance instructions and what you would need to do to bridge the gap in an overhead catenary system. And the answer is that basically even the longest clearance obstruction I can think of can probably be bridged just fine with an on-board battery.
Batteries would also let you avoid stringing wire over sidings, most yard tracks, etc. Current battery technology would not let you avoid overhead wire if your goal is full mainline electrification.
CSSHEGEWISCH How long would it take and how much money would it take to recharge a battery of that size?
Since it doesn't exist, I think the answer is - it can be designed to charge however fast you want, but there will be huge tradeoffs between speed, the effect on battery life, and the amount of equipment necessary for the charging system.
dpeltier Batteries would also let you avoid stringing wire over sidings, most yard tracks, etc. Current battery technology would not let you avoid overhead wire if your goal is full mainline electrification.
Which is what I was driving at when saying that equipping an electric locomotive with a battery would have advantages beyond providing an answer to low clearances.
Your math and assumptions on using LFP batteries seem reasonable.
The state of the art for commercially available batteries is 450kWhr/tonne, which would be enough for branchline use. These batteries are being made for electric aircraft, though I think least another 50% increase in specific energy is needed to make it viable.
The dismissal of the clearance issue(s) above is a non-starter. The claim of 25 foot clearance is being adequate does not fly at all. (at any potential)
Insulating underheight bridges is not cheap and does not always work (and adds to the clearance problems)
The issue of dealing with existing utilities won't be cheap either. Raising pole lines is a rather contentious issue around railroads, especially on shared pole lines where you discover how many scofflaws are out there not complying with NESC clearance rules. (Biggest violators are reckless and unthinking phone and especially fiber operators)
Wanna make things worse? - try lowering the tracks and find out how many pipelines were installed improperly. (railroads and utilities / pipeline companies tend to have a great deal of angst when they encounter each other)
Nobody seems to consider the run-offs that are required with this stuff.
mudchickenThe dismissal of the clearance issue(s) above is a non-starter. The claim of 25 foot clearance is being adequate does not fly at all. (at any potential)
Strangely enough, India seems to have no problems with 7.57 meter (~24' 10") clearance on double-stacks on their 25 kV electrified lines. About 1/3 of world lines are electrified: US about 1%, Germany about 60%, China about 65%.
jeffhergertThe government is good at unfunded mandates. PTC anyone?
For sure. But, the RRs brought that on themselves. Walked away from ATCS project distracted by some pretty merger mirages and some dude named EHH.
-Don (Random stuff, mostly about trains - what else? http://blerfblog.blogspot.com/)
Love this! Mike Iden et.al. are on the right track (literally?)
11 KV https://photos.app.goo.gl/iJkTqTe6bkKTv74g7
Not huge clearance under bridges... I would think we could do this with 25' wire most places.
dpeltier CSSHEGEWISCH How long would it take and how much money would it take to recharge a battery of that size? Since it doesn't exist, I think the answer is - it can be designed to charge however fast you want, but there will be huge tradeoffs between speed, the effect on battery life, and the amount of equipment necessary for the charging system. Dan
Battery tenders for bridging gaps would recharge en route. As fast as they discharged at least?
I'd bet you'd manage it. Get charge up enough for next gap, series of gaps, and regulate recharge accordingly.
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