What do you think is more powerful?

[spikejones52002]

Thank You Railway Man for the great source of Infomation on the

GG1.

Spike

[GP40-2]

...There is no circumstance where the tractive effort of a GG-1 can ever approach the tractive effort of an SD70ACe...

Really? Let's say both the ACe and GG1 are traveling at 50 MPH. For the sake of discussion, let's assume the locomotive's respective HP ratings are at the drawbar (e.g. assume machinery and aerodynamic losses are zero) So, we have an ACe producing 4300HP and the GG1 producing 4680HP @ 50MPH.

The ACe is producing 32,250 lbs. TE
The GG1 is producing 35,100 lbs. TE

The GG1 can pull more train than the ACe at 50MPH. Period. With the same weight train, the GG1 is pulling away from the ACe.

So some of you are saying "What about the ACe's fancy-smancy traction system?" Totally ineffective at those speeds. The AC'e traction system only comes into play at very low speed to allow the ACe to develop the high adhesion needed for the increased low speed tractive effort.

Besides, the GG1 has 303,000 lbs of adhesive weight on its drivers. Let's say the GG1 can convert only 22%-23% of the weight into pulling force. (probably a low estimate--more like 25% w/o sand and 30% with sand) That amounts to 70,000 lbs pull before you start to lose adhesion.

If the GG1 was overloading its motors to 8000HP @ 50MPH to accelerate a train, it would be producing 60,000 lbs TE. This is still well within its adhesive capacity, and it would be producing twice the TE of the ACe at this speed.

[ValorStorm]

...There is no circumstance where the tractive effort of a GG-1 can ever approach the tractive effort of an SD70ACe...

Really? Let's say both the ACe and GG1 are traveling at 50 MPH. For the sake of discussion, let's assume the locomotive's respective HP ratings are at the drawbar (e.g. assume machinery and aerodynamic losses are zero) So, we have an ACe producing 4300HP and the GG1 producing 4680HP @ 50MPH.

The ACe is producing 32,250 lbs. TE
The GG1 is producing 35,100 lbs. TE

The GG1 can pull more train than the ACe at 50MPH. Period. With the same weight train, the GG1 is pulling away from the ACe.

Tractive effort is the force that a locomotive can apply to its coupler to pull a train. It's true that the greater the speed of the engine, the more power is needed to produce a given tractive effort. But here is where I think some of us have been miscalculating.
Most locomotive builders calculate tractive effort based on a percentage of the weight placed on the driving wheels. This results in STARTING tractive effort, which is always the absolute maximum possible. Horsepower plays a roll, but in the case of North American motive power IT IS NOT THE PRIMARY CONSIDERATION WHEN DETERMINING TRACTIVE EFFORT. 25% for clean dry rail is the old standard right up until the advent of AC traction. In the case of AC traction, dynamometer tests have shown that the factor can often exceed 35%! This is not the case with DC traction. (Yes, this presupposes high horsepower).
In most cases, tractive effort limits the pulling power of locomotives only at very slow speeds. Above a few miles per hour, horsepower limits prevail. So please understand that "pulling power" & "tractive effort" aren't exactly synonymous. When we say that an SD70ACe exerts 157,000 pounds of CTE that means "at speed," including 50 mph! A GG-1 has a starting TE approaching 80,000 lbs. That's the maximum. It goes down from there.

the GG1 has 303,000 lbs of adhesive weight on its drivers. Let's say the GG1 can convert only 22%-23% of the weight into pulling force. (probably a low estimate--more like 25% w/o sand and 30% with sand) That amounts to 70,000 lbs pull before you start to lose adhesion.

So you DO know how to calculate tractive effort! What could possibly be the justification for the erroneous results?

[Railway Man]

It's hard to compare two locomotives when we're working from incomplete sets of data.  All I know of the GG1 is what's written on what appears to be the railroad's data sheet, which says 72,800 lbs maximum tractive effort (at what speed that's taken, and what % of adhesion, I know not), and 4,620 continuous horsepower (385 per motor, 12 motors).

These specs are taken from this sheet here, which appears to be a PRR sheet (comments?)

http://prr.railfan.net/diagrams/PRRdiagrams.html?diag=gg1.gif&sel=ele&sz=sm&fr=ge

Tractive effort at any given speed for any locomotive is calculated using the formula TE = (hp x 375)/speed.  For diesel-electric locomotives, the constant 375 is typically replaced by 308 to account for the 82% efficiency of the electric transmission.  For the GG1, for the sake of argument, let's assume the 385 horsepower per motor is taken at the output shaft, so using the formula,

10 mph: 173,250 lbs.

25 mph: 69,300 lbs.

50 mph: 34,650 lbs.

For the 4,300 hp SD70ACe, assuming it's only 82% efficient:

10 mph: 132,440 lbs.

25 mph: 52,976 lbs.

50 mph: 26,488 lbs.

Some caveats:

1.  I've seen statements that the GG1 could exert 9,500 hp at 49 mph.  I'm seeking an explanation how that number could be on a continuous basis.  Short-time, maybe, which might have been useful accelerating a light, short train -- and how short a time is short, anyway?  1-2 minutes at that kind of overload doesn't fill me with enthusiasm that this capability had practical operational value.

2.  The GG1 didn't have a wheel slip system that would enable it to get that kind of tractive effort at 10 mph.  The data says weight on drivers is 303,000 lbs.  Assuming that 25% adhesion was about as good as it would get, maximum TE on the locomotive at any speed would be 75,750 lbs.

3.  The SD70ACe probably is a little more efficient than 82%.  The data sheet for the similar SD9043MAC says it produces 185,000 lbs TE up to 11 mph (but also says CTE is 147,000 lbs., so perhaps there are heating limits on the A.C. transmission?).

I'm comfortable that from 0 to somewhere around 20 mph the SD70ACe can produce more useful tractive effort than the GG1.  At higher speeds the GG1, if the 4,620 hp is something that its traction motors can do continuously, will produce somewhat more tractive effort and pull away from the SD70ACe -- or maybe it will produce a lot more TE if the claims of immense horsepower at high speed are true, and if this hp could have been put to practical effect before exceeding the motor heating limits or exceeding the locomotive's adhesion.

(Not a sales plug, but every time these discussions come up, I reread the explanation of locomotive physics in the back of the Kalmbach "Contemporary Diesel Spotter's Guide," which is as succinct and complete an explanation of tractive effort, horsepower, adhesion, train resistance, and grade resistance as I have found.)

RWM 

 

 

 

 

 

[erikem]

1.  I've seen statements that the GG1 could exert 9,500 hp at 49 mph.  I'm seeking an explanation how that number could be on a continuous basis.  Short-time, maybe, which might have been useful accelerating a light, short train -- and how short a time is short, anyway?  1-2 minutes at that kind of overload doesn't fill me with enthusiasm that this capability had practical operational value.

The 9,500 hp is short term - don't know how short, depends one what is limiting the power output (motor heating, transformer primary winding?). 1-2 minutes overload wouldn't be much use for freight, but more than adequate for passenger service. 

 

2.  The GG1 didn't have a wheel slip system that would enable it to get that kind of tractive effort at 10 mph.  The data says weight on drivers is 303,000 lbs.  Assuming that 25% adhesion was about as good as it would get, maximum TE on the locomotive at any speed would be 75,750 lbs.

 

Even worse is that it had AC series motors with pulsating torque - though the springs on the quill drives probably filtered out much of that.

 

3.  The SD70ACe probably is a little more efficient than 82%.  The data sheet for the similar SD9043MAC says it produces 185,000 lbs TE up to 11 mph (but also says CTE is 147,000 lbs., so perhaps there are heating limits on the A.C. transmission?).

I wouldn't be surprised if there were heating limits on the traction motors - induction motors are rugged but not indestructable. I would imagine that the efficiency of the SD70ACe's transmission varies as a function of both tractive effort and speed. May be as low as 50% at low speeds and high TE, possibly 90% at somewhere around 30 MPH.

[ValorStorm]

Assuming that 25% adhesion was about as good as it would get, maximum TE on the (GG-1) at any speed would be 75,750 lbs.

And maximum TE is starting TE. And you calculated tractive effort correctly.

Now this is from the EMD website:

SD70ACe Performance Specifications
4,300 THP and locomotive equipped with EMD's
16-710G3C-T2 engine
EPA Tier-2 emissions certified

Tractive and braking effort capability
157,000 lbs continuous TE
191,000 lbs starting TE
106,000 lbs braking effort

Repeat: There is no possible way a GG-1 can have a continuous tractive effort rating anywhere near the 157,000 lbs of an SD70ACe, because a GG-1 can't have a starting tractive effort rating higher than 80,000 lbs.

The (hp x 375)/speed formula for TE served a purpose. It's not used so much anymore, likely because in physics terms, horsepower is "power" and tractive effort is "force." These are very different animals. It was confusing before, but now it's not. Bed time.

[Railway Man]

The (hp x 375)/speed formula for TE served a purpose. It's not used so much anymore, likely because in physics terms, horsepower is "power" and tractive effort is "force." These are very different animals.

Who doesn't use it any more!?!  Maybe I'm just an old-timer (I like to think of myself as chipper as a spring chicken but my knees say otherwise) but I've used this formula in my railroad job at least a dozen times this year, and it's the basis of the calculations in the train-performance  and locomotive-performance software we paid $$$$ dollars for and use for train schedule design and analysis.  It's in the AREMA "Practical Guide to Railroading" Manual too, Chapter 2, page 33.  Am I supposed to be using something else?

www.arema.org/eseries/scriptcontent/custom/e_arema/Practical_Guide/PGChapter2.pdf

RWM 

[GP40-2]

...There is no circumstance where the tractive effort of a GG-1 can ever approach the tractive effort of an SD70ACe...

Really? Let's say both the ACe and GG1 are traveling at 50 MPH. For the sake of discussion, let's assume the locomotive's respective HP ratings are at the drawbar (e.g. assume machinery and aerodynamic losses are zero) So, we have an ACe producing 4300HP and the GG1 producing 4680HP @ 50MPH.

The ACe is producing 32,250 lbs. TE
The GG1 is producing 35,100 lbs. TE

The GG1 can pull more train than the ACe at 50MPH. Period. With the same weight train, the GG1 is pulling away from the ACe.

Tractive effort is the force that a locomotive can apply to its coupler to pull a train. It's true that the greater the speed of the engine, the more power is needed to produce a given tractive effort. But here is where I think some of us have been miscalculating.
Most locomotive builders calculate tractive effort based on a percentage of the weight placed on the driving wheels. This results in STARTING tractive effort, which is always the absolute maximum possible. Horsepower plays a roll, but in the case of North American motive power IT IS NOT THE PRIMARY CONSIDERATION WHEN DETERMINING TRACTIVE EFFORT. 25% for clean dry rail is the old standard right up until the advent of AC traction. In the case of AC traction, dynamometer tests have shown that the factor can often exceed 35%! This is not the case with DC traction. (Yes, this presupposes high horsepower).
In most cases, tractive effort limits the pulling power of locomotives only at very slow speeds. Above a few miles per hour, horsepower limits prevail. So please understand that "pulling power" & "tractive effort" aren't exactly synonymous. When we say that an SD70ACe exerts 157,000 pounds of CTE that means "at speed," including 50 mph! A GG-1 has a starting TE approaching 80,000 lbs. That's the maximum. It goes down from there.

the GG1 has 303,000 lbs of adhesive weight on its drivers. Let's say the GG1 can convert only 22%-23% of the weight into pulling force. (probably a low estimate--more like 25% w/o sand and 30% with sand) That amounts to 70,000 lbs pull before you start to lose adhesion.

So you DO know how to calculate tractive effort! What could possibly be the justification for the erroneous results?

Wow! All I can say is you have no idea what you are talking about. Please take a basic physics class!!!

Do you really think an ACe can produce 157,000 lbs at "speed"? So you are saying that at 50MPH it is producing 157,000 lbs TE? Wow, that means it is producing 21,000 HP. I must of missed the memo that EMD has really uprated the 710!!!

You see kid, Horsepower and Tractive Effort are DIRECTLY related. There is no way to separate them when a locomotive is moving at any speed. I gave you the basic formula--obviously you can't even understand 9th grade math.

I'll repeat, at 50MPH the GG1 produces more TE than the ACe. If you don't understand that, you don't understand anything about tractive effort.

BTW, before you start lecturing me on what makes locomotives tick, I've worked in this industry for 3 decades and have a MSME (Master Science Mechanical Engineering). While at CSX, I worked directly with GE on developing the "heavy" AC4400, so I know a tad bit more than you about TE, HP and AC locomotive efficiency.

Please tell us your academic credentials and industry experience.

[GP40-2]

... I would imagine that the efficiency of the SD70ACe's transmission varies as a function of both tractive effort and speed. May be as low as 50% at low speeds and high TE, possibly 90% at somewhere around 30 MPH.

On GE AC's efficiency varies from a low of 85% while producing max. TE at low speed, to over 94% at 70+MPH. All the "experts" on this forum yap at CSX for using ACs on fast double stacks, but that's exactly the speed where they are the most efficient.

[erikem]

The (hp x 375)/speed formula for TE served a purpose. It's not used so much anymore, likely because in physics terms, horsepower is "power" and tractive effort is "force." These are very different animals. It was confusing before, but now it's not. Bed time.

Lessee, POWER=FORCExDISTANCE/TIME, and SPEED=DISTANCE/TIME, so POWER=FORCExSPEED and therefor POWER/SPEED=FORCExSPEED/SPEED=FORCE or FORCE=POWER/SPEED.

So the formula, TE(lbf)=(hp x 375)/speed(mph) is valid as long as the tractive effort is horsepower limited and not adhesion limited.

As for the GG-1 vs the SD70ACe, no one is arguing that the GG-1 has a low speed CTE anywhere near the SD70ACe - my calculation shows that the CTE of the SD70ACE will be horsepower limited above 9.2MPH (assuming 90% transmission efficiency).

[JayPotter]

my calculation shows that the CTE of the SD70ACE will be horsepower limited above 9.2MPH (assuming 90% transmission efficiency).

To what calculations were you referring?  I understand the concept of calculating the (maximum) continuous tractive effort of a DC-traction unit; but I'm confused by the concept of calculating the (nominal) continuous tractive effort of an AC-traction unit. 

 

 

[ValorStorm]

the GG1 has 303,000 lbs of adhesive weight on its drivers. Let's say the GG1 can convert only 22%-23% of the weight into pulling force.

So you DO know how to calculate tractive effort! What could possibly be the justification for the erroneous results?

Wow! All I can say is you have no idea what you are talking about. Please take a basic physics class!!!

Please calm down. I wasn't making fun of you. And thanx for calling me a "kid." I'm 51. Now the calculation was yours. Converting 22%-23% of the weight into pulling force results in the STARTING TRACTIVE EFFORT. Your answer was correct. EMD says the continuous tractive effort of their SD70ACe is 157,000 lbs. I have taken physics. But I wasn't a physics student. You've proven yourself the most knowledgeable in this thread. So I'm not daring you, I'm asking you, please provide the definition of "continuous tractive effort."

[timz]

EMD says the continuous tractive effort of their SD70ACe is 157,000 lbs.... please provide the definition of "continuous tractive effort."

Ah-- so that's the problem. EMD didn't bother including the clarification "157,000 lb continuous TE at 7 mph [or whatever it is]". They certainly never intended to suggest that the SD70 could produce 157,000 lb at 50 mph, or at 30 mph, or even at 10 mph. They just meant, if you want to pull a train up a hundred-mile hill, and the combination of grade and tonnage requires a TE of 157,000 lb, then the SD70 will fill the bill. They're not saying anything about how long it will take to get to the top.

(And they probably mean "adhesion permitting", too. If you send an SD70 up Cranberry with 3000 tons it won't always make it.)

[JayPotter]

The for-whatever-it's-worth approach that I take to the SD70ACe 191K "starting" figure and the 157K "continuous" figure is that (a) 191K is the maximum TE that the unit's adhesion-management software will allow it to produce; (b) it will only be able to reach that maximum level if rail conditions are very favorable (i.e. will allow a 46.8% adhesion factor); and (c) under normally expected rail conditions, the unit will have a 38.4% adhesion factor.  Those adhesion figures are based on a unit weight of 408K.

[chefjavier]

The for-whatever-it's-worth approach that I take to the SD70ACe 191K "starting" figure and the 157K "continuous" figure is that (a) 191K is the maximum TE that the unit's adhesion-management software will allow it to produce; (b) it will only be able to reach that maximum level if rail conditions are very favorable (i.e. will allow a 46.8% adhesion factor); and (c) under normally expected rail conditions, the unit will have a 38.4% adhesion factor.  Those adhesion figures are based on a unit weight of 408K.

Do you have a math formula or a equation that you use to get this answer ?

[chefjavier]

The for-whatever-it's-worth approach that I take to the SD70ACe 191K "starting" figure and the 157K "continuous" figure is that (a) 191K is the maximum TE that the unit's adhesion-management software will allow it to produce; (b) it will only be able to reach that maximum level if rail conditions are very favorable (i.e. will allow a 46.8% adhesion factor); and (c) under normally expected rail conditions, the unit will have a 38.4% adhesion factor.  Those adhesion figures are based on a unit weight of 408K.

Do you have a math formula or a equation that you use to get this answer.  

[beaulieu]

A few additions to the discussion; due to hardware and software limitations the SD70ACe max TE is not at starting but rather at a speed slightly above 1mph. The reasons for this are, first maximum friction coefficient between two pieces of steel of at least similar chemical makeup occurs with slippage not in static positions. Second at zero rotation speed (i.e. very low frequencies) the invertor isn't very efficient. And Third, the locomotive is using an updated version of the WS-10 wheelslip system first used in the SD40-2s, as the Doppler Shift is too slight for the radar system to give an accurate ground speed reading which is necessary for the Super Series wheelslip control to function. Maximum potential TE is possible with a slip rate of approx 3%. (i.e. wheel rotational speed is 3% greater than what would produce the actual ground speed).

[JayPotter]

In response to Javier's question, all of the figures that I cited were derived from the basic formula that "adhesion" is the percent of locomotive weight that the unit's adhesion-management system can convert into tractive effort.  So, for example, an SD70ACe that, according to EMD's figures, weighs 408K pounds and produces 191K pounds of TE would have an adhesion factor of 46.8% (i.e. 191 divided by 408) when producing that TE.  One reason that TE-related calculations become confusing is the concept of the "starting TE" figure (i.e. in this instance, 191K).  That figure isn't the maximum TE that an SD70ACe is mechanically capable of producing.  It's a software-imposed upper limit that's intended primarily to prevent excessive mechanical stress.  If (1) that limitation is removed; (2) rail conditions are extremely favorable; and (3) the unit needs, because of train weight, to produce more than 191K TE; then (4) the unit will produce more than 191K TE.  I generally find it more informative to refer to graphs of TE-versus-speed than to perform actual TE calculations.

[chefjavier]

In response to Javier's question, all of the figures that I cited were derived from the basic formula that "adhesion" is the percent of locomotive weight that the unit's adhesion-management system can convert into tractive effort.  So, for example, an SD70ACe that, according to EMD's figures, weighs 408K pounds and produces 191K pounds of TE would have an adhesion factor of 46.8% (i.e. 191 divided by 408) when producing that TE.  One reason that TE-related calculations become confusing is the concept of the "starting TE" figure (i.e. in this instance, 191K).  That figure isn't the maximum TE that an SD70ACe is mechanically capable of producing.  It's a software-imposed upper limit that's intended primarily to prevent excessive mechanical stress.  If (1) that limitation is removed; (2) rail conditions are extremely favorable; and (3) the unit needs, because of train weight, to produce more than 191K TE; then (4) the unit will produce more than 191K TE.  I generally find it more informative to refer to graphs of TE-versus-speed than to perform actual TE calculations.

JayPotter:

Thanks for the information. 

[ValorStorm]

And thanx to all since my last post for being diplomatic.

[Frisken]

Could we please compare it to a "modern" or at least something built at the same time as the ACe:s ?

I suggest the Swedish Iore which is a 6-axle Bombardier TRAXX-concept Electric AC 3ph traction motor electric locomotive. All data here is for 1 unit not 2 as they are coupled in pairs I don't see the point in complicating things.

 

Max  Tractive Effort  132k lbs  (600kN)

Weight 396832 lbs (180 metric Tons)

Top speed 49 mph (80 km/h) However when pulling 8600 metric ton ore trains they have a top speed of 60 km/h or 37 mph due to brake limitations.

HP:  7241 HP (5400kW)

I guess its not really comparable since axle loads are somewhat diffrent in the US and over here in Europe. 30 metric ton per axle here and around 33 metric ton per axle in the US.

 

IF a US railroad company for some reason ?(skyrocketing fuel costs, electricity prices down low ,copper cheaper than ever etc etc)  would ever electrify I'm guessing GE or someone else would build something even more powerful and specific for the US market. That is something I would personally like to see. But since capital investment isn't a big thing for US railroads of today I'm guessing this is something we'll never see.

 

Greetings from Hans from Sweden

[CNW 6000]

Well why don't we just settle this discussion and make up 2 trains that have identical weights & lengths.  We'll hook up an SD70ACe to one and the GG-1 to the other.  We'll time them and monitor speeds and train control performance.  If there's any GG-1s that run anyways...

If the GG-1 was that great...wouldn't they still be in use?  Wouldn't straight-electric freight engines be rampant if they were that great?  Other than AM(mostly on)TRAK who else in the US uses straight-electric locos?  I think that they aren't used for a reason.

[timz]

Correct-- because they cost $. Doesn't mean they can't pull.

On a 1000-ton train the GG1 will beat the SD70-- on the level, anyway. On a 12000-ton train the SD70 will win.

[Railway Man]

[In reference to electrification of freight railroads]: But since capital investment isn't a big thing for US railroads of today I'm guessing this is something we'll never see.

Not trying to hijack the thread, and perhaps something got lost in translation, but could you explain this for me, please?

RWM 

[Frisken]

Well there was one railroad operating a large Electric system however they had managment hellbent on destroying thier own railroad ... double maintanence posts in book keeping, renting their own cars from others. Showing fantasy earnings by totally ignoring track maintanence etc etc. Yeah you know the one.

 

Probably it is the capital investment that's the mayor hurdle these days, not seen any calculations on it but would probably pay itself in a couple of decades however not sure anyone want to make that sort of investment. Not seen any figures, probably also needs a minimum amount of  freight before it really becomes profitable.

 

Some streches that would have enough traffic and pops into my head is NS from Pennsylvania to Cleveland and on to Toledo & Chicago, Probably the CSX line parralleling it from Cleveland to Chicago also has enough traffic to warrant electrification. In the East probably UP from Chicago to Ogden, maybe UP:s streches in southern California into AZ and on to Texas, BNSF:s line through Southern Calf through AZ and on to St L. Down South Jacksonville,FL -> Manchester, GA on CSX also probably has enough traffic to warrant electrification. NS:s strech from Macon GA to Cincinatti, OH (maybe all the way to earlier named Cleveland -> chicago route however traffic is slower the last part there) would probably also have enough traffic. However that is just looking at tons/mile carried there are ofc other factors as proximity to cheap &reliable electric power along the line.

 

Back in the Steam days switching to Electrics would probably cut maintanence in half(have heard numbers as low as 10%) and number of locomotives needed cut down to 1/3 of the steam figure. Trackside maintanence is somewhat increased with the catenary and ofc also the electrical equipment associated with it. Also the cost of building your own power grid would probably put a dent into the economy aspect of things.

The formula for deciding wether to switch from diesel to electrics would look something like: electrics bill + catenary and support eq maintanence bill + loan repayments with intrest on new cat over 40 years + electric locomotives + maint on electric locomotives for 40 years IF this is bigger then the cost of new diesels + diesel maintenance for 40 years + diesel fuel for 40 years

then you probably shouldn't electrify said strech of rail. (Never seen any such figures thrown around so ...) 

The prices are probably hard to say but fuel beeing the expensive part for diesels and catenary system the most expensive one for electrics, a electric locomotive would probably be cheaper then a diesel locomotive of the same size, however don't quote me on that

 

Electrification is widely used in the rest of the world however the "diesel salesmen" probably stopped any such developments in the US. Might have been short-term profits aswell stopping it, don't know for sure. However I've always felt that short term profits and a major capital biz as railroading is isn't really a good match is it?

 

And please stop comparing GG-1:s (a 1930:s cutting edge locomotive) with a SD70ACe (a 1990:s cutting edge diesel) Electrics also has anti-slip and such features these days (even 1940:s designs had early variations of that here in Sweden)  GG-1 where excellent machines with low maintanance and all, probably lower then a SD70ACe even ... however Amtrak decided to "upgrade" to 25kV on the Eastern Corridor and GG-1:s got thier transformers made for 11,25kV filled with cement (might be one or two left but still no OH to run under with correct Voltage) so your purposed test will probably never be.

 

Ok ok I guess this is a boring post ... congratz you at least read this far down! Then I probably didn't wasted your time too much then then!

 

In response to Railway Man: with the big capital investments needed to electrify you have got to have the money on hand which I bet railroads like CN or UP might have at least partially or you got to borrow money, either of those options could make your short term profits drop  (money on hand probably means they are working to produce more money for you already or if you borrow you put further expenses to the balance sheet and no new incomes) which would make shareholders annoyed and it would ofc also be detrimental on the short term in the stock market, further reducing your odds at good extensions on loans etc for the major investment you have made. Thus I'm saying no major Railroad would be willing to do this. It would be a major "green" publicity thing and the green lobby would applaud it probably but financially it would at first be a economical nightmare.

 

Greetings Hans from Sweden 

[YoHo1975]

Europe is significantly smaller then the US and has much newer infrastructure (due to a certain world war destroying most of the old stuff)

The cost to electrify the transcon for instance would be astronomical. And lets not forget that the US already has an electrical generation and transmission issue. So it's not just the capital costs for the railroads, but the capital costs to build the power generation and transmission lines. And what kind of green generation plants will they use? Nuclear power is billions and billions per station. It would be an interesting Chicken and egg issue if they built coal and the green movement would have kittens.

Even the increased cost of MOW, because you'll need to have more crews stationed in remote locations. I can't even begin to imagine. 

 

So no, it's not as simple as railroads not willing to shell out the capital. As if they don't already spend billions maintaining their infrastructure. 

[Frisken]

 

Probably it is the capital investment that's the mayor hurdle these days, not seen any calculations on it but would probably pay itself in a couple of decades however not sure anyone want to make that sort of investment. Not seen any figures, probably also needs a minimum amount of  freight before it really becomes profitable.

However that is just looking at tons/mile carried there are ofc other factors as proximity to cheap &reliable electric power along the line.

Trackside maintanence is somewhat increased with the catenary and ofc also the electrical equipment associated with it. Also the cost of building your own power grid would probably put a dent into the economy aspect of things.

The formula for deciding wether to switch from diesel to electrics would look something like: electrics bill + catenary and support eq maintanence bill + loan repayments with intrest on new cat over 40 years + electric locomotives + maint on electric locomotives for 40 years IF this is bigger then the cost of new diesels + diesel maintenance for 40 years + diesel fuel for 40 years

then you probably shouldn't electrify said strech of rail. (Never seen any such figures thrown around so ...) 

The prices are probably hard to say but fuel beeing the expensive part for diesels and catenary system the most expensive one for electrics, a electric locomotive would probably be cheaper then a diesel locomotive of the same size, however don't quote me on that

 

Electrification is widely used in the rest of the world however the "diesel salesmen" probably stopped any such developments in the US. Might have been short-term profits aswell stopping it, don't know for sure. However I've always felt that short term profits and a major capital biz as railroading is isn't really a good match is it?

 

In response to Railway Man: with the big capital investments needed to electrify you have got to have the money on hand which I bet railroads like CN or UP might have at least partially or you got to borrow money, either of those options could make your short term profits drop  (money on hand probably means they are working to produce more money for you already or if you borrow you put further expenses to the balance sheet and no new incomes) which would make shareholders annoyed and it would ofc also be detrimental on the short term in the stock market, further reducing your odds at good extensions on loans etc for the major investment you have made. Thus I'm saying no major Railroad would be willing to do this. It would be a major "green" publicity thing and the green lobby would applaud it probably but financially it would at first be a economical nightmare.

 

 

Well I thought I had answered some of those questions already and I really hate quote:ing myself but well it was a rather huge post, and I don't blame you for not reading it all through. Some things I could ofc clarify.

 

First I didn't want to write in plain text that the US probably has a too crappy powergrid for electrification but now I've done that aswell

 

And on the Maintanance issue ... well there isn't much about it. Costs would ofc be slightly higher for maint but about having ppl placed on remote locations etc, well if that was the case  then there probably already is ppl placed there and as such they are already needed and already beeing payed for. Catenerary (sp?) has a very long lifespan and if nothing happens outside the ordinary (de-railings etc) then its just a streched piece of copper wire. And its beeing constantly polished from below by carbon all day.

Some of the regular MOW crews ofc need High Voltage Educations, and a couple of ppl handling refueling of diesels are probably out of work and could be re-educated and some additions to the regular MOW train as a over head wire access car. And the optical inspection vehicle (usually used for track inspections) probably needs a new video camera pointing upwards looking at the OH-wire aswell. But this would ofc be a minor cost.

 

Well examples of green power is probably unessacary but Hydropower is one, windpower probably could be used if you could smooth things over with the help of the local power grid (see previous note on US Power Grid ) when the wind doesn't produce enough power. Nuclear is ofc another option if the power usage motivates it. Its cost efficent for sure. One other thing is that even if you build your own Nuclear plant / hydro damms / wind power farm the obvious advantage is ofc that the cost is almost a constant (or at least not as much affected by the oil price) which is not the current case with fuel prices which seems to fluctate heavily over time, on the other hand you could probably buy 40 years worth of fuel to make sure you pay the same price for the fuel for the next 40 years, this is essentially what you would be doing if you where to build your own Power plant of any kind. Intrest rates is then the major player here instead of fuel rates

 

I'm not 100% sure electrification is a solution to  anything atm. However raised fuel prices could probably be offset by it. And sitting on your hands probably won't produce anything results. Decreasing pollution to cope with new demands in pollution legislation, which at least some states seems intrested in raising the bar on (probably those without many coal power plants)

 

I would love to do a comparison but any real numbers on this is hard to come by. A Euro vs US comparison is also hard since here Axle loads are lighter and what I've found so far not even the swedish Ore traffic @30 metric ton / axle comes close to US axle-load limits of roughly 32.8 metric ton / axle. The extra axle load makes it hard to do a comparison between them in terms of efficency.

 

Say for instant that CSX decided to electrify ( right) all thier major mainlines and build power generation for it. If this is somewhere around 65% of thier total traffic and fuel usage, That would reduce thier fuel bill with roughly 750 Million dollars leaving those money to be put into paying of thier latest and probably world-record sized loan, so what does 750 million dollars in intrest and downpayments over the next 40 years give us then ? Well according to the formula

a = K _n * p/100
( 1+ p/100) ⁿ - 1

 

I'm not that good at economical terms in english but this should be self explaining i hope. Paying 750 Millions for 40 years at 8% intrest (those loaners would probably want something for their money) 

 

K _n = 750 * (

[Krazykat112079]

As I see it the question hasn't really been answered.  I see the SD70ACE being compared to the GG1.  I assume that the SD70ACE is the most powerful diesel (I admit, I haven't followed that aspect of diesel technology) since it is used in the comparison, but is the GG1 really the pinnacle of brute electric locomotive power?  I refuse to believe that in 65 years something more powerful hasn't come along.  What about the Toasters?  Aren't they rated at 7k HP?  That is almost double the GG1 and higher HP than even the DD40.

I envision that the spirit of the question is similar to that of the world's strongest man competition.  Just keep on adding weight until one drops out. 

[Rail1435]

The power of a diesel-electric locomotive is limitetd by the power of diesel engine built in!

The maximal power at wheelrim is approximately 30% of the nominal power at engine output axle.

On an electric engine, you can for a short time request 150% of the nominal power, which is not possible with diesel locomotives.

 

For people wich can read french, please use followink link (only the figure is in english):

http://documents.epfl.ch/users/a/al/allenbac/www/TF49.htm

select "Thermique ou electrique" : comparison between electric and diesel-electric locomotives withe same weight and same mechanical part.

 The most powerful single body locomotives will run in China next year (or yet in 2008?): 9,6 MW at wheelrims on CoCo! Three different series are now in building phase by 3 different pairs of constructors.

Jean-Marc, Switzerland

[blade]

the big boys were pretty masssive and powerful at 4-8-8-4 wheel arrangement.