Electric Power through Tunnels?

[greyhounds]

OK, playing off another topic - using nuclear watch batteries to power locomotives - there was a swerve into something useful.

At least one major route, the BNSF through the Cascade Tunnel, is capacity constrained by the need to clear the tunnel of exhaust fumes before another train can go through.

If the diesel engines could be shut down, or idled, through the tunnel, this restraint could be reduced.

How difficult would it be to run a third rail, or catenary, through the tunnel and provide power to the traction motors from that source instead of using the diesel engines to generate the power. This would eliminate, or reduce, the need to clear the tunnel of exhaust.

The transmission would have to be what was normally generated by the locomotive, but it would only have to go the length of the tunnel. Once clear of the tunnel the locomotives would resume generating their own electricity. (Yes, I know, the locomotives would need some sort of pick up device.)

[chad thomas]

I would think it would be more cost effective to improve the ventilation system than modify locomotives. You would have to add electric throttle controll gear not found on a diesel/electric as this is done with governing the prime mover. Plus this would go against standardization of the motive power fleet.

[arbfbe]

Most of the equipment need on a straight electric locomotive is already in place on a diesel locomotive. For very short applications such as a tunnel or a mountain grade the voltage in the trolley could indeed be the same as the output of the main alternator of the locomotive reducing the additional equipment that would have to be added to the locomotive.

It would be an interesting concept far cheaper than electrifying entire divisions. Still it would involve modifying a large number of locomotives and no one in the railroad industry appears to want to be the first one to give it a try.

[nanaimo73]

GN ran Electrics through this tunnel until 1956. Could you fit the electrical converting equipment into existing locomotives? Slightly used electrics are availible in Mexico. Adding and dropping these units would take a lot more time than that saved by not ventilating.This would lower clearance as well.

[TH&B]

My idea would be to use 3rd rail and have electric helpers. They would just be older deisels converted, a little bit like slug units. These "electric motors" could be used as helpers in conjunction with the thru deisels, or for lighter trains as helpers and shut the deisels down for the pass thru the tunnel portion.

The investment shouldn't be a heck of alot, realy. The 3rd rail is of coausre a hazzard but your not supposed to be on the tracks anyways and the live rail would just be switched off when not in use.

Use low voltage like subway trains do, no need for any expensive on board transformer.

[arbfbe]

Railroads dislike helper districts though the crews could certainly add the straight electrics to their consists at the crew change points. They could use the electrics to control the diesels with the straight electrics dead until the tunnel is reached. At that time the diesels could be placed in idle when the electrics are connected to the electric grid. This could be done with a command through the MU cables or by using the diesel consist as a DPU remote set when the electrics are added. There is no reason the third rail has to be ground level, it could be mounted on the ceiling of the tunnel for safety. Wire is only used for trolley in open spaces where support systems, ie trolley poles and tensioned wires need to be built. Lighter wire is better then. In a tunnel you already have the roof of the tunnel for support so a heavier feed such as a steel rail can be used to feed the pantograph. No one would be tempted to steal the steel rail like they would with copper wire. Limiting the electric district to just the tunnel and a mile or less on each side of it would reduce capital costs immensly. Hostlers at the terminals with diesels to shuttle the electrics to an from trains at the terminals would preclude the need to wire these areas as well.

The SP did one study that showed an SD45 had 85% of what was needed to convert it to an electric locomotive should they decide to electrify Donner Pass.

[Leon Silverman]

If you packed these old engines with batteries that were charged by the dynamic brake system (instead of dissapating the energy to the air), you might be able to pull the train on battery power alone long enough to avoid filling the tunnel with diesel fumes. This would result in a significant fuel savings since you essentially have a hybrid diesel locomotive.

[chad thomas]

And why would they not just improve the ventilation system?

[arbfbe]

The ventilation system involves moving large volumes of air. The weight of this air is not inconsequential. It has to move miles to clear the tunnel. On BNSF's Flathead Tunnel in Montana there are two engines from GP35s (5000 hp total) used to power the fans to move the air. The tunnel the CP built on Rogers? Pas uses two engines from SD70s (8600 hp total) for that purpose. Moving air is a science and the design of the tunnel and ventilation system have to be engineered so everything is in balance. The tunnels and ventilation shafts can only move so much air. The power sources and fans provided can push all the air that can be moved in the flumes provided. You can add bigger engines and fans but they cannot likely move any more air through the flumes. So you need to add more or bigger ducts for the air as well as adding bigger fans and engines. That requires hard rock mining and concrete work. Concrete is smoother than unfinished rock and will move more air. More doors inside the tunnel and more vent ducts could be added and the fans and engines could remain the same but that is still an expensive under taking.

They could also build a parallel tunnel on the same grade or find an alternative grade so that the new tunnel slopes opposite the current one and there are no uphill trains in either tunnel in a double track operation. These are both expensive solutions.

[TH&B]

One reason I thought of 3rd rail at ground level was to keep the hight clearance in the tunnel without realy enlarging the bore.

Another advantage of straight electrics is in higher mountains were the air gets thinner, this is a strain for deisels ((ie. Tennesee pass)).

Maybe the two GP35 prime movers and generators that power the fans could be used to generate the electricity for the 3rd rail and use two SD frames to put pickup shoes on and use as the electric helper slugs;-) Not realy more efficient, but keeps the exaust outside the tunnel and maybe they can run a few more thru per day.

[BaltACD]

First one to step up to the plate with half a Billion dollars gets to implement their 'cheap' fix.

[greyhounds]

QUOTE: Originally posted by BaltACD

First one to step up to the plate with half a Billion dollars gets to implement their 'cheap' fix.

How is this going to cost $500 million?

The best idea I read was notionally to:

1) get some old SD40s

2) pull out their engines and generators for stationary mount outside the tunnel

3) lay a third rail through the tunnel drawing power from the stationary engines

4) use the loco shells as electrical powed slugs through the tunnel

5) have the de-engined SD40s shuttle back and forth through the tunnel powering trains - thus keeping the exhaust out of the tunnel

6) you could keep one "engined" locomotive in the shuttle consist to move it beyond the third rail

I don't know wether it would work or not. It's just an idea I had. But I'm confident it could be done for less the $500 million.

Reminds me of the @#$% trainmaster at Centrailia who said he'd have to put on an entire extra yard engine shift to make one extra block.

[BaltACD]

QUOTE: Originally posted by greyhounds

QUOTE: Originally posted by BaltACD

First one to step up to the plate with half a Billion dollars gets to implement their 'cheap' fix.

How is this going to cost $500 million?

The best idea I read was notionally to:

1) get some old SD40s

2) pull out their engines and generators for stationary mount outside the tunnel

3) lay a third rail through the tunnel drawing power from the stationary engines

4) use the loco shells as electrical powed slugs through the tunnel

5) have the de-engined SD40s shuttle back and forth through the tunnel powering trains - thus keeping the exhaust out of the tunnel

6) you could keep one "engined" locomotive in the shuttle consist to move it beyond the third rail

I don't know wether it would work or not. It's just an idea I had. But I'm confident it could be done for less the $500 million.

Reminds me of the @#$% trainmaster at Centrailia who said he'd have to put on an entire extra yard engine shift to make one extra block.

Efficient railroads don't run on 'back yard kluge' engineering.; especially in dangerous terrain, and the Cascades and Cascade tunnel certanily qualify as dangerous terrain. If the continued electrification of Cascade tunnel would have been economically justified, electrification would not have been stopped in 1956.

[stmtrolleyguy]

QUOTE: Originally posted by greyhounds

QUOTE: Originally posted by BaltACD

First one to step up to the plate with half a Billion dollars gets to implement their 'cheap' fix.

How is this going to cost $500 million?

The best idea I read was notionally to:

1) get some old SD40s

2) pull out their engines and generators for stationary mount outside the tunnel

3) lay a third rail through the tunnel drawing power from the stationary engines

4) use the loco shells as electrical powed slugs through the tunnel

5) have the de-engined SD40s shuttle back and forth through the tunnel powering trains - thus keeping the exhaust out of the tunnel

6) you could keep one "engined" locomotive in the shuttle consist to move it beyond the third rail

I don't know wether it would work or not. It's just an idea I had. But I'm confident it could be done for less the $500 million.

Reminds me of the @#$% trainmaster at Centrailia who said he'd have to put on an entire extra yard engine shift to make one extra block.

Try this one out for size. Use the old loco engines outside the tunnel. Use them to provide the electric feed. But control the train in the tunnel from outside. Set the locos in the tunnel to run 8 or something with no current in the third rail (or some setting that takes power and makes the wheels turn when they get juice.)

Notch up the old loco outside the tunnel, make more current, engine inside the tunnel gets more juice for the traction motors, off it goes through the tunnel. Think of it like a road slug setup of sorts, but the slug is on the train and the engine doesn't leave the yard. It would really by just like a model railroad. Speed/motion controled with the amount of juice in the third rail.

[GP40-2]

This idea is silly for a whole bunch of economic reasons that I'm not going to waste my time responding to...

440cuin: "Another advantage of straight electrics is in higher mountains were the air gets thinner, this is a strain for deisels ((ie. Tennesee pass))."

That is totally incorrect.

Diesel locomotives have turbochargers that can supply more than enough air for any operating environment found in North America. Modern locomotives do not loose power at higher railroad altitudes.

[RudyRockvilleMD]

As somebody mentioned the Great Northern electrified Cascade Tunnel with overhead catenary, but then they didn't have double stacks. Today you would only need the electrification through the tunnel itself so perhaps 3 rd rail DC power could be used.

It might be possible to do the same thing the New Haven, and Metro North did which was to buy diesel locomotives that could run on either on-board power or on 3rd rail electricity. By shutting down or idling the diesel prime mover the electric locomotive could pull the train through the tunnel on the third rail, and then restart the prime mover once the train has cleared the tunnel.

[greyhounds]

QUOTE:

Efficient railroads don't run on 'back yard kluge' engineering.; especially in dangerous terrain, and the Cascades and Cascade tunnel certanily qualify as dangerous terrain. If the continued electrification of Cascade tunnel would have been economically justified, electrification would not have been stopped in 1956.

Look, this may be a silly idea, but it's MY silly idea.

Nobody is talking about "back yard kluge" engineering. It's a freaking concept that would have to be properly engineered.

However, "efficient" railroads will always make the best use of their existing resources and if they can use old SD40s to increase the capacity of the Cascade Tunnel in lieu of spending megabucs for another solution an "efficient" railroad will do that. It would have to be evaluated against other courses of action and one of those other courses would certainly be "do nothing".

As for:

QUOTE: If the continued electrification of Cascade tunnel would have been economically justified, electrification would not have been stopped in 1956.

That was 49 years ago! In '56 they could put an exhaust evacuation system on the tunnel and run the diesels through with no problems. That world went away. They made the right decision in '56, but the right decision in '56 isn't going to be the right decision in '05.

Change is continuous, efficiency is forever.

[BNSFGP38]

The effiency you would gain would lost by the need to switch locomotives before entering and after exiting or the cost of provideing all locomotives with shoes's.

[Anonymous]

QUOTE: Originally posted by nanaimo73

GN ran Electrics through this tunnel until 1956. Could you fit the electrical converting equipment into existing locomotives? Slightly used electrics are availible in Mexico. Adding and dropping these units would take a lot more time than that saved by not ventilating.This would lower clearance as well.

As of last summer, those "slightly used" Mexican E60 electrics were sitting on an overgrown spur track near Harlingen TX, and not in particularly good shape.

[arbfbe]

The cost of electrification of the tunnel would only make sense if it could improve capacity through relieving the need to ventilate the tunnel. The delay from adding and removing the electric power has to be weighed against current delays while waiting for the tunnel to clear now. I see no need to shut down the diesels while the are idling in the tunnel, the friction of the train against the air in the tunnel will likely drag those low level pollutants out with the train.

Far from being a "silly" idea it has enough potential to merit some study. It would make a great project for an engineering class at a university in the Pacific Northwest.

[nanaimo73]

First of all, it's not going to happen, but it is very interesting.
Second, this is not far from Tacoma where 6 former BC Rail GF6C electrics were just cut up.
Third, Arbfbe mentioned CP uses 2 SD70 prime movers at Rogers Pass. So that no one missunderstands him, they were new and not taken out of SD70s. I think they were more like SD60s myself. CP ordered these engines from GMD and then asked for the "Red Barns" to have SD40 engines which caused a lot of problems.
The Mount MacDonald tunnel is covered in depth in the March 1990 Trains.It is 48,304 feet long. Cascade is North America's second longest rail tunnel at 41,152'. (Until UP builds that proposed 12 mile tunnel in eastern Oregon.
The GN electrification went from Skykomi***o Wenatchee.They used ALCO-GE Y-1 1-C+C-1s and two W 2-D+D-2 motors, one of which was turned into UP coal-fired turbine #80.
The grade in the tunnel is 1.57% with the summit on the east end at only 2883', so altitude is not a problem.
It is going to tie up track time having these helpers come back west, so it can't save any time.
Please keep this thread going.

[chad thomas]

QUOTE: Originally posted by GP40-2

This idea is silly for a whole bunch of economic reasons that I'm not going to waste my time responding to...

440cuin: "Another advantage of straight electrics is in higher mountains were the air gets thinner, this is a strain for deisels ((ie. Tennesee pass))."

That is totally incorrect.

Diesel locomotives have turbochargers that can supply more than enough air for any operating environment found in North America. Modern locomotives do not loose power at higher railroad altitudes.

I think you are wrong here. Diesels do loose power with altitude. I believe the factor is 2% per every 1000'. (Newer microprocessor controlled locomotives probably have less loss due to the fact that they can adjust fuel/air ratio constantly)

[rrock]

As has been pointed out in the case of the Cascade tunnel, it's all about bottom line economics. I lived in Seattle for 20 years and spent some time observing operations on the former GN line through the Cascades, and have assimilated quite a bit of the history of the line.

Nanaimo73's point about helpers tieing up track time highlights but one major factor. Helper operation was originally based at Wenatchee and Skykomish so that, among other factors, trains running upgrade could be started on less severe slopes, and to avoid winter operation (most of the time) in heavy snowfall that accumulates near the tunnel. There are only a few long passing sidings between Wenatchee and Skykomish. Helper or specially equipped motive power movement in such situations is never perfect (running one side to the other); inevitably there is a need to dead head helpers.

Which points to another major economic factor. Other than a few rare cases, BNSF can theorectically run any main line motive power through the Cascade tunnel- BNSF power, leased power, borrowed power, etc. No specialty power to maintain on the roster, investment in specialty expensive (relative to the cost of mass-produced motive power) motive power, and do forth.

Track maintenance costs across the Cascades are comparitively high due to travel distances, moutain roads, and winter weather. This would only increase further with catenary or third rail.

In the balance, the cost of maintaining the two 1,000 HP (if I remember correctly) electric (utility power with generator back-up) remotely controlled turbines used to "flush" the air in the tunnel is small.

Also, as part of the greater economic picture, BNSF utilization of other cross Cascades routes in the northwest (Stampede Pass and the former SP&S line on the north shore of the Columbia river) comes into play.

[Anonymous]

You are not proposing anything new. This is exactly how the FL9s operated into Grand Central Terminal. Also the FM lightweights and the United Aircraft Turbotrains could run off of the third rail. The technology is nothing that could be considered "rocket science". All the engineer had to do to switch from diesel to electric (or back) was to shut off the throttle and then run the throttle back up.

However, doing this on a limited number of passenger locomotives is one thing. Outfitting an entire roster of locomotives that might conceivably run through the Cascade Tunnel is an entirely different matter and would not be cost effective. And outfitting a limited number gets back to the helper district problems. Even if you outfit enough locomotives to run all of the trains through the tunnel without helpers you must change power at either end of the district instead of running the power through. Time consuming and expensive.

[GP40-2]

QUOTE: Originally posted by chad thomas

I think you are wrong here. Diesels do loose power with altitude. I believe the factor is 2% per every 1000'. (Newer microprocessor controlled locomotives probably have less loss due to the fact that they can adjust fuel/air ratio constantly)

[nanaimo73]

The maximum altitude here is 2883' , about half of the joint line south of Denver.

[MichaelSol]

The Cascade Tunnel is a problem but not the only problem on Stevens Pass. The Eastbound approach is also presents a similar constraint. The Pass is nearly at capacity, and there are no likely solutions.

Washington DOT, 2004:

"Various studies have been performed over the years on Stevens Pass capacity. While with BN in 1994, MLM personnel utilized model simulation, as part of the analysis that ultimately justified reopening Stampede Pass, to analyze maximum operating capabilities over Stevens Pass. The primary geographical feature of the route is the nearly 8-mile long Cascade Tunnel. Due to its length the tunnel must be flushed behind every train that operates through it.

"The prevailing grade approaching the tunnel is 2.2% eastbound to the west portal and 1.7% through the tunnel to near the east Portal. Consequently, the time required for eastbound trains to traverse the tunnel, including flushing time behind the train, can be up to 55 minutes. Westbound trains, predominantly moving on a descending grade through the tunnel at track speed, essentially act as a “plunger”, forcing air ahead of the train and minimizing flu***imes. The tunnel can be cleared for the next movement behind a westbound train in approximately 25 minutes. Maximum speed for freight trains in either direction is 25-MPH. The various analyses previously performed (some of which have been performed by MLM and HDR personnel) have generally concluded that sustainable capacity through the tunnel is about 28-trains/day, given a relatively even split between eastbound and westbound trains, with surge capability to 30 to 31 trains/day under specific conditions."

Analysis MLM performed for POS and POT in mid-2002 indicated that BNSF was operating an average of approximately 20 trains/day through Stevens Pass, with peak day train volumes of about 24-trains/day. MLM and HDR do not believe those volumes have changed a great deal from 2002. Consequently, we believe BNSF has room to add 4 to 8 trains/day on the route before reaching volumes that will begin to tax the capacity of the route. Opinion on the capacity limitations of the route have generally focused on the tunnel as the primary limiting factor.

"During the analyses performed at BN in 1994, however, model simulation revealed that the grade and geography on both sides of the tunnel were equally important factors in limiting throughput volumes, particularly the eastbound ascending grade between Skykomish and Scenic. This segment, a distance of 13 miles between meet/pass sidings, is on a 2.2% ascending grade. The grade continues eastward from Scenic through most of the length of the tunnel. Consequently, eastbound trains traverse approximately 20 miles of 1.7% to 2.2% ascending grade with Scenic as the only location for meet/pass capability between Skykomish and Berne (just east of the eastern portal of the tunnel).

"Due to the geography, adding additional main line track or meet/pass sidings would be problematical at best as the right of way predominantly sits on a shelf above the Skykomish River, with a sheer rock wall on the other side. To test the impact of the segment between Skykomish and Scenic during the model simulation analysis in 1994, trains were “free-flowed” through the tunnel as if there were no requirements for tunnel flushing. That analysis determined that free-flowing the tunnel under the same train operating scenarios did not increase overall throughput on the route, indicating that the long, single track eastbound segment on ascending grade is as much of a limiting factor for maximum throughput as is the tunnel itself.

"This was verified in the 1994 report performed by HDR personnel."

Electrification to solve tunnel exhaust evacuation limitations would be a complete waste of time from the standpoint of adding capacity to the route.

Best regards, Michael Sol

[jchnhtfd]

Several miscellaneous thoughts...

First, Chad, don't be hurt -- you have some good ideas. Some of us need to remember that, if we have better knowledge or experience in some areas, we need to teach, not belittle. There are very few folks on this forum from whom I have not learned something; conversely, I hope that I have helped some others learn something, too.

The electrification idea is intriguing. The problems have, I think, been covered pretty well in some of the respones, though. In most areas where electrification has been done in the US, it is worth noting that the electrification almost always stretched from one crew/engine terminal to another. Thus -- in those days -- a train would come in from somewhere, and both the engine(s) and crew would be changed to electric for the service to beyond the problem area, where they would change back. But, and it is a big but, also in those days almost all trains used home power. Further, that home power was really home -- a given engine would spend all its useful life, in many cases, operating out of one terminal, sometimes with just one crew. Today, most engines run through from somewhere over the horizon in both directions: the motive power is not uncoupled from the train except at terminals. Thus what made operating sense, or at least didn't get in the way, in the old days of steam just doesn't any more.

Last thought -- lot of talk about GN, but let's not forget the Milwaukee Road operations!

[BNSFGP38]

For all intents and purposes diesels dont lose power at altitiude. How ever cooling that hot engine thats climbing the mountain is a different issue.[xx(]

[nanaimo73]

Which tunnel between Michigan and Ontario had electrics ? Was it the NYC tunnel at Detroit or the CN tunnel from Sarnia to Port Huron ? Or both ?
Ventilation was the reason the BC Rail Tumbler line was electrified. Those two tunnels were 29,570' and 19,536'.