Main Line Electrifications

[gfjwilmde]

I've read some of your messages and it has me confused. Although I'm a machinist, I've also been in some training classes learning about electricity(for safety training[required]). My understanding about the subject is, that it's easier to move(transport)electricity when it's ac rather than dc. I was taught that you can dump up ac to a higher voltage than dc, thus making it better to transmit across greater distances. Another thing I've learned in the 12+ yrs that I've been working around electric locomotives is that all they are no more than converters and 'step down' transformers. Ac cannot be used directly to the traction motors because of the pulsations in them. So the converters change ac over to dc and at the same time smoothes out the pulsations. Once this is done then its changed back to ac(or stays dc) and then 'stepped down to a safe and usable voltage for the traction motors. In fact...many of your modern diesels operate similarly. The diesel locomotive's generator(altenator) is actually producing ac current and is changed and 'stepped down' silmilar to what I explained earlier. The one downside to European or Asian rail systems is this, their electric locomotives are very lightweight. Most of the electrics barely weigh over 100 tons. Trying to pull a heavy train with those is an effort in futility. On the other hand...when electric freight operations were in their heyday, many of the railroads had very big, very heavy and very powerfull(at that time) electrics pulling most anything with very little in the way of mu'ing. Anyway...I believe there should have been an extensive network of both diesel and electric rail lines in this country ages ago. Many of the northeastern cities were very concerned about pollution caused by the steam locomotives, so railroads like Pennsy and New Haven electified much of their eastern or urban territories to cut down on smoke emmissions. Well, don't think for one minute that diesels don't put out a significant amount of fumes either. That's one reason why there should be more use of electric rail lines across the country than ever before. Surely...there are many in urban areas whom have no choice, but to live near(or right next to) an active rail line that has significant traffic flow. Surely to hear the rubble of the high horsepower diesels and the stench of diesel exhaust as they blast(or crawl) through a residential area is very uncomfortable. Sometimes, the smell of the exhaust lingers long after the train has departed. No to mention if the train is just sitting there waiting for traffic to clear so it can be on it's way is very inconsiderate to the surrounding populace. When I was a teen, I used to hangout in the Conrail yards near Jersey City, New Jersey. Many of the trains crept through the city, usually blowing out huge plumes of smoke, blackening everything around. Sometimes, if there was a cylinder that was bad, there would also be oil flying out with the exhaust as well. Yes...maybe some day we'll return to moving heavy freight trains with electics again...some day.



GLENN
A R E A L RAILROADER!!!!!
A R E A L AMTRAKER!!!!!

[Anonymous]

MichaelSol:

I will auto correct myself. Spacing on the polish system ( 3kV dc) is between 5 and 20 miles - depending on the traffic density. Typical substation is about 4,5 MW continuus and currents may reach 2,6 kA when ET42 (6600 hp) class loco is working hard.

Considering that a single Little Joe was 5500 hp - that is about the same - buuut - with longer substation spacing (28 miles - as yau claim) the loss of voltage might be higher. I suspect that currents could go up to 3 kA then... impressive to say the least.

As for the 'giant' savings. Maybe the better word would be 'substantial'. Electrification pays off when the line is havily trafficked. With longer segments and euro-style traffic density (think 3 minute headways) with longer segments there are, ferinstance more chances to regenerate energy. If one really tried then 25 kV would suffice for 200 or so miles - with low enough traffic density. BTW - spacing of 25 kV system is about 40-60 miles.

But nonetheless - in the US type of railroading electrification does not make sense at all. The traffic density is too low (there are too few places with really tight spacing), trains are, by euro standards, underpowered and speeds are moderate.

EDIT: as for clearances - what is the problem to step down from 25 kV to say - 8,33 kV? That would be the same as clearances for 3 kV DC.

Isambard:

When polish electrification was coined there was a plan to electrify a coal line from Upper Silesia to the Gdynia seaport - in that tume that line run along the border with Germany. Also - electrification started in 1935 - the war started in 1939. By 1939 there were only 8 locos and several EMUS in service. Obviously later it was a moot point.

When the war ended communists simply started with what was there - so 3 kV DCsystem was there to stay - esp since the BIg Brother also electrified with 3kV DC

[arbfbe]

The easiest way to regulate the speed on an AC motor is to vary the frequency of the current. Today there are different alternatives. I believe the N&W AC system in it's earliest forms had units that had three throttle positions, stop, half speed and full speed. Imagine the lunging between throttle postions there! I suppose the speed control was the reason for the low frequencies of some systems.

[martin.knoepfel]

Hugh Jampton is right. When Germany started electrification, 50 Hz didn't seem practicable for railway purposes. Germany, Austria, Sweden, Norway and Switzerland run on 15 kv 16,7 Hz AC. The Swiss federal railways recently admitted, they would use 25 kv 50 Hz AC, if they could start from scratch. However, Hungary successfully tried out 50 Hz very early, in the twenties or thirties of the 20th century with the Kando engines.

I know of natural-gas-fired and nuclear power plants in the Netherlands.

[Hugh Jampton]

16 2/3 Hz was originally chosen as it's easy to make, being 1/3 of 50Hz,, and commutated motors will run at this frequency, which means that simple resistance control can be used.

[Isambard]

QUOTE: Originally posted by uzurpator


BTW Poland (and a few other countries) had chosen 3 kV DC because Germans used 15 kV 16,6 Hz system. It was 1935 then so obviously it was a national defense issue :)

By choosing 15 kV 16,6 Hz, German equipment would be prevented from running on Polish rails in the event of an invasion? Was it in fact a consideration in the Polish decision? In view of the predominance of steam power at the time I would have thought that this would not have been a significant consideration.

Apart from that can anyone comment on the use of 16,6 Hz transmission by Germany rather than a higher frequency? Was this an inheritance from the early days of AC transmission? Was use of 16,6 Hz general elsewhere? Is it still used?

As an aside, I understand that Ontario Hydro choose 25 Hz over 60 Hz for domestic purposes in the early days of AC, due to concerns that 60 Hz was more dangerous to personnel and customers. As a result in the 1950's Ontario had a massive project to convert all domestic and industrial equipment in southern Ontario from 25 Hz to 60Hz, the by then prevailing standard in the rest of Ontario and North America. Think of it-every vacuum cleaner, refridgerator and so on!

As other questions for anyone:
What is/are the source(s) for electrical power for the Dutch railway system- fossil fueled power stations or nuclear, domestic Dutch or imported?

Is the transmission frequency for electrified North American railroads usually at 60 Hz, the standard domestic frequency?

[jchnhtfd]

Pause for thought...

The considerations for using AC vs. DC differ depending on whether one is talking about transmission, distribution, or powering motors.

First, transmission. Until relatively recently, AC was the only form of electrical power which was really usable for transmission. Why? Because it is possible to transform AC from one voltage to another using a simple static device: the transformer, which is dead simple, highly reliable, and very very efficient. And it is necessary, economically, to use very high voltages for transmission, since power losses are inversely proportional to the square of the voltage -- but you don't want to either generate or use electricity at high voltages. More recently, solid state converters have come into use for conversion of AC to DC, or vice versa, at very high voltages. With these converters, which are not cheap and are nowhere near as reliable as transformers, it is possible to get the advantages of very to extreme high voltage transmission of power with DC, which has some real advantages.

For local distribution -- say in a city -- I do not see an advantage to DC, if for no other reason economics: you still need moderately high voltage for distribution (23 kV is typical) but you don't want that in the individual user's establishments (anything over 480 is regarded as very high in the user's environment, and takes special handling). So each user, or group of users, would need the converters rather than transformers.

For power use, the advantages of AC are almost overwhelming for most applications. A three phase (or single phase, in small applications) AC motor is, again, a near zero maintenance, dead simple, device. A DC motor is neither.

Railroad applications are just a wee bit different. First, although there were a very very few multi-phase AC overhead systems, they were horribly complex and difficult to maintain, so you were limited to single phase at some frequency or other (it really doesn't matter, within reason). But large single phase AC motors aren't practical, so the railroads used DC traction motors. In the bad old days, this meant motor-generator sets to convert the AC (stepped down via a transformer) to get DC. Some outfits ran the numbers and decided that complexity wasn't worth it, and used DC for distribution -- with lots of substations. Others decided that it was, and used AC at much higher voltages (like 11 kV) for distribution. Again, however, solid state devices get into the equation, and with them it is now quite practical, and 'best practice', to use solid state devices to take either DC or single phase AC, at some voltage compatible with the catenary or whatever, convert it in the locomotive to DC, and reconvert it to frequency controlled three-phase AC to drive the traction motors.

Do you use AC or DC for your power distribution (catenary/third rail)? That would be a decision grounded in economics. My bet would be that in most cases, AC would win, if you were starting from scratch. If you are using existing infrastructure -- run what you brung.

[CSSHEGEWISCH]

Although dual-mode (FL9-type) locomotives to cover a tunnel-type electrification sound like a good idea to improve utilization, they still have their limitations. Amtrak generally does not allow its P32's to stray beyond Albany, which pretty much restricts their range to not a whole lot too far beyond the end of third rail. Dual-mode locomotives on a tunnel electrification could not be allowed to stray too far from the mainline that has the tunnel, which would restrict their utilization to some extent. They would also be more expensive than conventional diesel-electrics, which would make it hard to justify their purchase when their operating range would still be restricted.

[Anonymous]

arbfbe,

Thanks for providing your insights into the Milwaukee electrification decisions. I have a few followup questions (and Michael Sol, please chip in if you want):

1. Was there any significant difference between the current used by the New Haven et al with their FL9's and the 3600 v DC used by the Milwaukee that prevented them from utilizing an FL9 type locomotive on the PCE? Did the Milwaukee ever consider an electric/diesel hybrid like the FL9 for the PCE? Do you know if the FL9 was a considerably more expensive locomotive than standard diesels or an electric like the Little Joes?

2. With regards to the possibility of fulling electrifying the mainline from Harlowtown to the Puget Sound, when the Milwaukee received trackage rights into Portland, wouldn't that have put a crimp into having a dedicated electric fleet west of Harlowtown? You can't put catenary over someone elses track. If as I had speculated the Milwaukee could have requested (and received) trackage rights over the SP&S between Spokane and Portland as well as the I-5 corridor, that also would have required a substantial fleet of diesels in the PNW. Any run through freights would have to have been fully dieselized or run in electric/diesel combos, so there would be the added cost of adding/taking out electrics at certain points in the case of the latter. And since mergers were an ever increasing fact of life for the railroad industry, there is some credibility to the argument that the uniqueness of the electrification may have scared off potential suitors, especially in an industry that practically worships at the alter of standardization.

Don't get me wrong, I believe in hindsight that for the Milwaukee (or the GN for that matter) to have given up on electrification was a bad idea, given today's diesel fuel costs (and BNSF's current capacity constraints through the Cascade Tunnel). If either entity had kept their electrification (and assuming the Milwaukee had survived into the present), said electrification would be paying huge divedends right now.

[arbfbe]

QUOTE: Originally posted by futuremodal

QUOTE: Originally posted by arbfbe

To feed trailing diesels from a lead electric would require quite a substantial bus system. The spring loaded bars on the GN Y -1 class electrics come to mind. There are some problems with that between units account the high voltages in the areas where crew members are working. The MILW boxcabs did bus the power between units but those units were almost permanently coupled and the feeders were above the roof line.

As I percieve such power MU'ing, the combined electric and diesel loco lashup would act as each other's road slug depending on which power source is being utilized. Road slugs don't need such heavy duty bus bar connections, right? If I understand correctly, the bus bars were used to transmit "unconverted" 3600v DC current to the trailing units, while a road slug connection transmits "converted" current to the trailing unit(s).

QUOTE:
All the opportunities MILW management had to make their railroad work and they repeatedly chose the wrong course.

Can you be more specific? For posterity's sake, what would you have done differently regarding Milwaukee's decision nexus circa 1970 as to what to do with the electrification, save it, scrap it, modernize it, and/or expand it?

My long held belief was that Milwaukee should have scrapped the catenary back in the 1950's when dieselization became commonplace, e.g. the inherent savings of standardization. That belief has been modified in recent months with the information provided on this forum regarding the operating cost savings of electrification and the seemingly permanent price increases in diesel fuel, to the point where I now think electrification of certain segments would have made sense if a bi-modal power solution could be had "on the fly", e.g. some sort of emulation of the FL9 concept. For the Milwaukee in the 1970's, that FL9 technology concept existed in conjunction with Milwaukee's own innovations in running diesels and electrics together. Perhaps Milwaukee should have kept the wires between Harlowtown and Butte, as well as Haugen and Avery, but also considered taking down the wires between Butte and Haugen since that was basically water level gradient. On the Cascade segment, keep the wires between Beverly and Kittitas for the Saddle Mountain crossing as well as between Hyak and Maple Valley for the Snoqualmie Pass grade.

*********************************************************************************************

The problem with the bussing of power from a single source are many fold. Note the slug units you refer to are commonly a single unit feeding one or both ends of the slug of diesel powered locomotives. We are talking 600v DC with a max of about 1000 amps per traction motor on the slug. That is still a lot of watts to carry through the wires. Now carry that over to your suggestion for the MILW and you are looking for the head end electric to provide 3000+vDC to 12 or 18 trailing traction motors if they are electric locomotives. But they would be diesels, with 600vDC traction motors which the Joes could not provide. So in all likely hood, you would be building a new class of 600V DC electric units to lead the trailing diesels. It would be far simpler to build a new class of diesels with pantographs with 3000 volt traction motors. However, that would mean a complete redesign of the units to these specs using non-standard main generators, traction motors and control circuitry. Prohibitively expensive and far out of reach to the MILW. Also, trying to feed three or four locomotives from one pantograph just begs to have an arc between the pan shoe and the trolley wire in the heavy frost which would burn through the wire causing massive delays until the wire is repaired.

There is just not likely any feasible substitute for an existing electrification than to build purely electric locomotives for the line voltage in use. Changing DC voltages in the MILW era would involve motor generator sets on each locomotive if the 600v traction motors were retained which would have made the diesel units too heavy for the bridge structures on the MILW. The ideas of short stretches of line with electrification in mountain grade territory seems to run counter to rebuilding the entire existing electrical system in it's entirety to more fully utilize the specially built electric locomotives that would be necessary.

Now as to poor business judgement by MILW managers at the highest levels...
The topic that has arisen on this thread is the idea MILW could have had a total upgrade to the electrification to state of the art standards at NO COST to themselves. What a deal! Instead, they elected to pass on that gift horse. The reason I have heard was the proposal from the consortium included GE and there was a clause that the MILW could only purchase their locomotives from GE during the first 20 yrs of the contract. While it would be unlikely EMD or any other supplier would design a competing locomotive at a competitive price in that time and the life span of the original electrics could easily exceed that 20 yr period, MILW management was unwilling to accept such a restriction. Come on now, someone offers to build you a new house for free and the only restriction is the next two cars you buy have to be Fords and you walk away from that offer?!?!? Is that short sighted or what?

As to the other chances the MILW management had to redeem themselves, I can refer you to the previous threads you have participated in on this forum. Specifically the Booz, Allen & Hamilton assessment that the profits were in the long haul including the Pacific Coast extension and not in the granger lines of the MILW. Yet, MILW management abandoned the profitable lines and kept focused on the lines that were losing them money. You can search the other MILW threads on this forum to refresh your memory if you like.

What would I have done with the electrification in the 1950's and 1960's? Expand it, of course. Each MILW boxcab has the same rating as the current F, SD or GP 9 series units of the 1950's. The Joes, at 5500 hp were equal to almost 4 GP9s in mu. It would take the diesel builders until post 2000 to come up with a single prime mover of 6000 hp to best the Joes. (The DD series of UP units do not count as they are just two diesels on a single chassis. All the eliminated was the drawbars between two units.) The Black Mesa & Lake Powell units of the1970s were far ahead of the diesels of that era. There were serious alternatives to motor generator types of substations that the MILW could have used to increase the load capacity of the electrification of the existing lines at a far lower cost than building mg substations. So I say, electrify the gap in Idaho, replace the trolley poles using concrete or steel structures and buy new locomotives. Leave all the diesels save for branchline power east of Harlowton until you can electrify the rest of the mainlines. If the power companies and suppliers will do this for you at no substantial charges to yourself, welcome them into the board room with open arms.

Unfortunately, MILW management was bent of getting out of the railroad business by merging the MILW with any other railroad that would take them. Their primary choice seemed to be the C&NW which was not the strongest line in the pile. In order to make themselves more attractive to a suitor, the managers decided that standardization was desirable and electrification was nonstandard no matter how well it worked. Well, Plan A with the merger scenario did not work but Plan B, make the MILW the best transcontinental line to Seattle using other people's money to upgrade the electrification was dismissed in favor of pursueing Plan A2, A3 and finally Plan C, dump the money making parts of the system to look again at Plan A3, A4 and who knows how many other merger related ideas. The one finally pursued with relish was inclusion into the BN system since BN was required to consider it as part of their original merger authority granted by the ICC. On it's death throes, the final Plan A was with the GTW but the Soo Line snatched that opportunity away. Instead of the MILW lines being abandoned in the midwest in favor of the merged railroad's trackage, it became a situation where the Soo Line trackage was abandoned and spun off in favor of the MILW lines. Yes, indeed what happened was the SOO Line managers came to run what was left of the MILW granger lines.

[MichaelSol]

QUOTE: Originally posted by uzurpator
Obviously these are giant saivngs.

Still nervous when engineering cost analysis is structured entirely on words like "giant."

With 1973 technology, rectifiers and inverters, Milwaukee Road studies found that 25 kv Ac and the 3600 vDC systems cost approximately the same to operate. While there were endless arguments about the idea that AC "should" cost less to operate, in fact it didn't. We looked and looked.

The difference in construction costs were small .... DC cost about 10% more, overall, to construct at the time. For existing DC systems, we could find no economic incentive to change systems unless someone just wanted to spend a lot of money for political reasons. And that was the bottom line when we actually looked at numbers ... replacing an existing DC electrification with an AC system invariably generated a negative rate of return unless you could obtain the money for free.

This is the single reason why Italy did not convert to 6kV DC and why most nations have been extremely slow to convert to an AC "standard" that affects, at best, a few international trains. While there are operating advantages to both the higher voltage DC and the AC, they simply were not worth the cost of replacing the existing systems. That is, nothing is realistically being purchased that justifies the cost. Holland has a unique situation of a system operating right at capacity for which a hgher voltage something, DC or AC, is the only feasible solution.

For a long system tapping from multiple AC supplies, the "clean" nature of DC avoided both loss of phase and phase problems as trains ran through power from those multiple suppliers. For existing rail installations, safety clearances came down in favor of the DC systems.

DC has evolved considerably since the early 1970s. DC is now the preferred means of long distance high voltage power transmission. Inverter and rectifier technology has improved by leaps and bounds, and their costs have dropped substantially. I suspect that the small advantage that AC systems had in construction costs thirty years ago has disappeared over shorter distances. At very high voltage, DC now has the cost advantage at transmission distances of approximately 400 miles or more and this cost advantage increases with distance. Likewise, DC's superior utilization of the carrier cross section reduces power losses and increases transmission efficiency substantially over AC.

As hgh voltage AC supply lines are gradually converted over the next twenty years to high voltage DC, the irony will be that rail systems which are utilizing AC at any voltage will be stranded.

They will have to invest in inverter and rectifier substations. At that point, the construction cost advantage will clearly be with DC railway electrification and AC will be viewed as an archaic and expensive albeit interesting relic.

Best regards, Michael Sol

[MichaelSol]

QUOTE: Originally posted by uzurpator

3 kV system capable of 6 MW output requires something about 3 mile substation spacing. 25 kV will happily work with 30 miles.

Milwaukee Road's 3600 vDC substations, which had continuous ratings typically of 4.8 MW or 7.2 MW, were all spaced 28-30 miles.

Best regards, Michael Sol

[Anonymous]

There are more advantages to the 25 kV/50 hz system then just industry standard (despite the fact that it cuts the cost right there - off the shelf equipment rocks).

Higher frequencies mean smaller transformers - good for EMUS when you want to mount a transformer underfloor (and keep the weight down).

Higher voltage means less substations. 3 kV system capable of 6 MW output requires something about 3 mile substation spacing. 25 kV will happily work with 30 miles. The reason why BMLP or Sishen-Saldanha run at 50 kV is because it saves the substations. I believe that whole BMLP is fed from a single 'outlet' :D. (BTW whole 600 miles of sishen-saldanha use just 8 substations - voltage may drop as low as 25 kV between then) Obviously these are giant saivngs.

And lastly - higher voltage means less maintenance and machinery for the catenary. 3 kV system pretty much requires two contact wires - while 25 kV will work with a single one - and of a smaller diameter.

Once multi-system equipment starts to be widely avalible there will be a giant pu***oward 25 kV/50 Hz system all over Europe (esp in DC countries).

BTW Poland (and a few other countries) had chosen 3 kV DC because Germans used 15 kV 16,6 Hz system. It was 1935 then so obviously it was a national defense issue :)

BTW - in the case of the US the 50 kV transcons and 25 kV everywhere else would make sense. But frankly - I can't really see a justification for the expense in the current operating schemes. Wires provide benefits that would not be used by US freight railroads.

[martin.knoepfel]

The Dutch are building a new freight-only-line, the Betuweljin, from the big port of Rotterdam to the German Ruhr-region, which is still heavily industrialized. It will run with
25 kv 50 Hz
As to the other railroad-lines in the Netherlands, they study the conversion to AC. But you have to know, that the Dutch have a very large passenger business and they run their railroad practically like a big nationwide suburban-system. Freight is less important because of competition from trucks and especially barges.

The decision to electrify the Betuweljin with a new system - it connects to 15 kv, 16,7 Hz in Germany - hast to do with technical progress. Now, it has become much cheaper to build multi-system-electric-engines than a few decades ago. Most probably, this played a role when Denmark electrified with 25 kv 50 Hz. 50 Hz has a large advantage: the European grid-system runs on this frequency. No need for specific railroad-systems.

[Anonymous]

QUOTE: Originally posted by arbfbe

To feed trailing diesels from a lead electric would require quite a substantial bus system. The spring loaded bars on the GN Y -1 class electrics come to mind. There are some problems with that between units account the high voltages in the areas where crew members are working. The MILW boxcabs did bus the power between units but those units were almost permanently coupled and the feeders were above the roof line.

As I percieve such power MU'ing, the combined electric and diesel loco lashup would act as each other's road slug depending on which power source is being utilized. Road slugs don't need such heavy duty bus bar connections, right? If I understand correctly, the bus bars were used to transmit "unconverted" 3600v DC current to the trailing units, while a road slug connection transmits "converted" current to the trailing unit(s).

QUOTE:
All the opportunities MILW management had to make their railroad work and they repeatedly chose the wrong course.

Can you be more specific? For posterity's sake, what would you have done differently regarding Milwaukee's decision nexus circa 1970 as to what to do with the electrification, save it, scrap it, modernize it, and/or expand it?

My long held belief was that Milwaukee should have scrapped the catenary back in the 1950's when dieselization became commonplace, e.g. the inherent savings of standardization. That belief has been modified in recent months with the information provided on this forum regarding the operating cost savings of electrification and the seemingly permanent price increases in diesel fuel, to the point where I now think electrification of certain segments would have made sense if a bi-modal power solution could be had "on the fly", e.g. some sort of emulation of the FL9 concept. For the Milwaukee in the 1970's, that FL9 technology concept existed in conjunction with Milwaukee's own innovations in running diesels and electrics together. Perhaps Milwaukee should have kept the wires between Harlowtown and Butte, as well as Haugen and Avery, but also considered taking down the wires between Butte and Haugen since that was basically water level gradient. On the Cascade segment, keep the wires between Beverly and Kittitas for the Saddle Mountain crossing as well as between Hyak and Maple Valley for the Snoqualmie Pass grade.

[Anonymous]

Ragarding electricity, here is how things are here In Croatia right now:

137km of 3000V DC electricity
984km of 25000 AC electricity

[MichaelSol]

QUOTE: Originally posted by 440cuin

heard the Dutch Railways (NS) are in the process of converting from DC to the 25kv European standard. I thought it was because the older DC system would be inadiquate for future loads on the railway. Why else do you think they would go through such a big expensive conversion?

Well, it's not happening soon. The costs of upgrading the entire system (both rolling stock and the infrastructure) to a high voltage are phenomenally high, and even excluding the costs of rolling stock, would cost more than 2 billion Guilders, oops, euros. Considering this cost barrier, it is unlikely that conversion, if it happens, is going to happen very soon.

The problem is that the Dutch system is very densely utilized. When a 1500 vDC train is accelerating, it can use up to 6 MW of power or more, corresponding to a load current of 4000 amps. This is HUGE and requires a substantially more robust system than a 3000 or 3600 vDC system. This is totally unlike American freight electric railway practice, such as it was, where there is little power demand, by comparison, because the trains spend most of their time at speed.

In contrast, Dutch trains spend most of their time either accelerating or slowing down unless you are out in the "country" going to Eindhoven or some such place. The current demands of all these trains constantly accelerating is in dramatic contrast to what we think of as piddly little trains on a light electrification. The power demands are in reality enormous because of the low voltage and high acceleration demands on the system by large numbers of such trains.

France recognized the same dilemma and started 25 kV electrification more than 40 years ago. Yet, France still has 50% of its electrified railways powered by 1500 v DC.

New Dutch railway construction is prepared for 25 kV AC, but continues to be operated at 1500 vDC and probably will be for many years to come, although international routes operate at the AC standard, or dual/ 3,000 vDC for trains to Belgium.

Best regards, Michael Sol

[TH&B]

Michael;
That is very interesting what you say about electric railways. I heard the Dutch Railways (NS) are in the process of converting from DC to the 25kv European standard. I thought it was because the older DC system would be inadiquate for future loads on the railway. Why else do you think they would go through such a big expensive conversion?

I also know that Denmark electrified seemingly idioticaly with 25kv when the only other railway systems it conects with at each end of the country use 15kv , Germany and Sweden.

Based on all this information it suddenly sounds like it would be obviously more cost effective to electrify in the USA, but none is doing it. I would also think one standard for the whole country would be the best, but would that realy be best? Or should each company choose for itself what it thinks is best?

If BNSF or any other class 1 was to electrify what would be the best choice of electricity?

[arbfbe]

The first major component in 25K and 50K electric locomotives is a transformer to bring the voltage down to a lower level. That is not needed in a DC fed loco. While the transformer can be expensive you do need some weight to ballast the units for pulling.

According to one SP study, about 85% of all the components need for an electric locomotive are found on a Diesel Electric. The SP was considering the cost of converting SD45 units which would become surplus by an electrification on Donner Pass to electrics needed to operate the line under catenary.

To feed trailing diesels from a lead electric would require quite a substantial bus system. The spring loaded bars on the GN Y -1 class electrics come to mind. There are some problems with that between units account the high voltages in the areas where crew members are working. The MILW boxcabs did bus the power between units but those units were almost permanently coupled and the feeders were above the roof line. The best way to use bimodal units would be to follow the FL9 model and put a power pick up on all the units. Diesels coming into Harlow would have the prime movers knocked in the head (railroad terminology for shutting down the diesel) and the pantographs raised. The controls to raise and lower tha pan would be included in the 27 pin mu cables. That would make those some expensive, custom designed diesels so it would likely be best just to change diesels out for electrics in the long run. The life span of the electric will exceed that of the diesel by a factor of 3-5 times so you would be scrapping the electric components in the bimodal units along with the diesel components which seems like a waste of capital and resources.

All the opportunities MILW management had to make their railroad work and they repeatedly chose the wrong course. Their blind obsession to make the MILW a plain vanilla railroad with no deviation from industry standards so as to make the railroad a merger candidate with any other broken down midwestern granger line has cost the investors, the employees and shippers from Louisville, KY to Seattle dearly over the years. Someone should go to jail to protect them from being strung up from a 3600 v DC trolley pole in 16 mile canyon in the dark of the night..............and then grounded between the copper and the steel. No ratlesnakes will be injured in the making of this movie.

[MichaelSol]

QUOTE: Originally posted by martin.knoepfel

A point for the AC-system. When South Africa built a new ore-hauler, the electrified it with high-tension AC 50 HZ

50kvAC almost always exists under specific circumstances:

1) wide open country with no clearance problems,

2) a single tap available for the orginal AC supply.

Best regards, Michael Sol

[martin.knoepfel]

Even these days, crude is stil cheaper than 25 years ago during the second oil crisis. That is why I don't expect any large-scale mainline-electrification in the US oder CDN soon.

In Italy, they made some studies to increase tension from 3 to 6kv DC, but they did not (yet?) convert any railroad-lines to that system.

A point for the AC-system. When South Africa built a new ore-hauler, the electrified it with high-tension AC 50 HZ

[MichaelSol]

QUOTE: Originally posted by Townsend

QUOTE: quoting Michael Sol
DC is better over long distances. I don't know where the idea comes from, but it is only a truism that AC is a better means of transporting high voltage power. It's previous advantage was only in the ease of conversion to different voltages, but in fact, DC is a superior form of long distance, high voltage electric power transmission. As technology has reduced the cost of converting DC power, its advantages have increased to the point where high voltage DC is now the preferred means of long distance electric power transmission.

I am not to sure on that. In Britain 1500 volts was the standard before the Second World War, with the exeption of the Southern Railway, but the railways did not have the money for large scale electrification. When the money became available Post War in the 1950's it was decided to electrify at 25kv industrial frequency. For new electrification since the 1950's 25kv has been the way the go. Other voltages have been extensions to existing systems. If the difference is so small way have new projects all been high voltage AC. In addition i dont now of good loco standard motor that can handle much over 1200 volts so how would high voltage DC be used in motors.

The statement referred to DC transmission, not railway electrification.

But, with regard to step down from transmission voltage to operating voltage, you might ponder how Milwaukee Road used 3600 volts DC to supply the GE 750 series traction motors on the Little Joe electrics.

Best regards, Michael Sol

[MichaelSol]

QUOTE: Originally posted by futuremodal
What I am getting at is if it is possible for an electric loco to feed power to MU'ed diesels (and vis versa) while going through long tunnels, e.g. a hypothetical re-electrification of BNSF's Cascade Tunnel. This would make it possible to eliminate the need for time consuming ventilation of the tunnel. The thought I had was that there would be no need to electrify entire subdivisions, rather concentrate the catenary in those places with the long tunnels or steepest grades, then run a combined consist of electric and diesels as a segregated FL9. The diesels would feed the electric sans catenary (e.g. the electric loco would act as a road slug when there was no catenary), while the electric(s) would conversely feed the diesels' traction motors short term in the tunnel (where the diesels would act as road slugs).

Requires some modified diesel units, but its a very interesting idea. Take it one step further -- those modified diesels enter electric territory. The diesel engine shuts down but, behind an electric providing both power and pick-up, the diesel units continue to operate, more efficiently because the diesel engine limitations are not present, and more cheaply because electric power costs are cheaper than the cost per equivalent gallon of fuel. The Diesel units become, for the duration of their run under a wire, straight electrics with no wear and tear on the component most prone to failure, the diesel engine. The number of straight electrics required is considerably reduced.

The diesel-electrics no longer lose power to altitude, temperature and engine age; they are, for their run under the wire, more powerful than when running on their own.

Interesting idea.

Best regards, Michael Sol

[Anonymous]

QUOTE: Originally posted by mvlandsw

QUOTE: Originally posted by futuremodal

QUOTE: Originally posted by MichaelSol

AC would probably be used, but regarding DC, Milwaukee Road used a 3600 vDC system. It's 5,500 hp Little Joes used approximately 1200 amps, or 1400 if the Joe went to its overload capacity of 7000 hp. The catenary used two 500,000 cm copper wires, with auxilliary feeder cable augmenting the catenary through either a 500,000 cm copper feeder, or a 750,000 cm aluminum feeder cable, with 4,000 or 6,000 kW substations located at approximately 28 mile intervals. The system could typically handle two 5,500 hp Little Joes and a four unit Boxcab helper, 7000 hp, without overheating the catenary.

It routinely paid for itself, even with relatively light usage, every 8-10 years.

Best regards, Michael Sol

Michael,

In the Milwaukee thread, you had mentioned the MU'ing of electrics and diesels by the Milwaukee. Was this strictly one man control from the cab of the electric, or was there ever a situation where the diesels could draw current from the "mother" electric?

The diesels produced their own power. They did not drawany power from the electric locomotive or the overhead wire.

Diesels produce their own power??!!?? Well, DUH![}:)]

What I am getting at is if it is possible for an electric loco to feed power to MU'ed diesels (and vis versa) while going through long tunnels, e.g. a hypothetical re-electrification of BNSF's Cascade Tunnel. This would make it possible to eliminate the need for time consuming ventilation of the tunnel. The thought I had was that there would be no need to electrify entire subdivisions, rather concentrate the catenary in those places with the long tunnels or steepest grades, then run a combined consist of electric and diesels as a segregated FL9. The diesels would feed the electric sans catenary (e.g. the electric loco would act as a road slug when there was no catenary), while the electric(s) would conversely feed the diesels' traction motors short term in the tunnel (where the diesels would act as road slugs).

For the Cascade Tunnel, it would allow a "back to the future" scenario for the Stevens Pass line wherein the wires are only strung through the tunnel itself, as was done in the original electrification of the old Cascade Tunnel. However, instead of needing separate crews (and subsequent crew districts in an isolated area) as was done with the old GN operation, you would have only your road crew throwing the switch enroute when the catenary is reached (and subsequently ended).

Certainly, the technology exists without expensive complications.

[MichaelSol]

QUOTE: Originally posted by dehusman

I doubt whether any railroads have active electrification plans. It is incredibly expensive initially. It requires huge permanent physical plant investments and it requires new locomotives that are restricted to just one portion of the railroad. There are very few locomotive savings because you still need virtually the same number of engines to haul the trains away from the electrified portion and you have the added delay of changing engines at the boundry point.

Bottom line is the costs are greater to electrify than the savings in fuel.

Admittedly, I get nervous when engineering and economic decisions are founded upon adjectives such as "incredibly," and "huge," as opposed to use of specific numbers.

However, let me offer a couple of suggestions. When Milwaukee decided to abandon its electrification in 1973, I discussed it with retired Milwaukee Road Electrical Engineers L.W. Wylie and H.R. Morgan, as well as with British Rail's expert, H.F. Brown, and engineers familiar with both the Milwaukee and GN electrifications, Walter Gordon, E.E. Van Ness, Gordon Rogers, and others. The last three named and I participated in a formal study on the project, consulting with Wylie, Morgan and Brown.

At that time, diesel fuel was 8 cents a gallon, but had begun its historic rise. Historically, the increase in diesel fuel costs was always faster than corresponding electric power costs, partcularly in the U.S. West with its large installed base of hydroelectric power. This has remained true.

I had discussed the matter with the Montana Power Company, and someone else on our team discussed it with Puget Power & Light, which was the electric power supplier for Milwaukee Road's Coast Division.

One of the big surprises in our study was the offer by the Electric Utilities that, if the Milwaukee felt that it needed to completely rebuild its system around an AC concept, and scrap entirely the DC system, that they would be glad to participate and fund the physical plant.

Why?

Utilities were already seeing that the future prospects of transmission line construction were becoming dimmer and dimmer, with land acquisition costs, lawsuits, condemnation proceedings, environmental reviews and the like making the prospects of new power lines less and less likely, and more and more expensive.

It was cheaper for the utilities to construct a high voltage line on the railroad right-of-way, AND construct the contact wire and distribution system for a railroad electrification, than it was to go out and try and acquire its own right of way from scratch.

At that point in time, the Milwaukee's big bargaining chip was that it owned the existing 110 kAC line in Montana, Idaho and Washington, and leased power transmission use to the power companies. In turn, because of the historic and strategic location of the Milwaukee's AC lines, they were heavily used by the power companies and by the BPA. This is one reason that Milwaukee Road obtained its electric power for trains for free.

So, these companies were very nervous about Milwaukee's intentions. Had Milwaukee asked, the power companies would have gladly stepped in, done a major rebuild to upgrade the AC line capacity, and installed contact wire and supply for an AC railroad electrification for free.

As it was, the 800 miles of right-of-way was a huge prize. The scrap value of the copper in the existing system, alone, was worth $23 million.

We were all quite surprised, then, when Milwaukee not only failed to take advantage of the rebuilding offer, but turned around and sold the lines. Montana Power Company bought the Montana AC transmission system, including right of way, for $3.5 million. The scrap value of the copper alone in the AC lines of the Montana portion of the system was worth $6 million. Later, I asked the president of the Montana Power Company about that, and he said they were all kind of flabbergasted. "We were ready to pay a much higher price," and suggested they had thought they could pay as high as $20-25 million.

QUOTE: Originally posted by dehusman

There are very few locomotive savings because you still need virtually the same number of engines to haul the trains away from the electrified portion and you have the added delay of changing engines at the boundry point.

This is not true. A 1968 study at the Milwaukee showed that because of higher hp per unit available, higher overall availability, as well as substantial overload capacity, 40 electric units would offer the same capacity to the Milwaukee as 120 of the highest hp diesel-electric units then available.

When economic service life was considered, 240 to 360 diesel units would be necessary to match the 40 electric units, because of the historically short service life of diesel-electric units in heavy mainline road service, which at that time was about 8-10 years, whereas the DC Electrics had an economic service life of more than 30 years in heavy mainline use.

Changeover times were not a factor. Because of the FRA 500 mile inspection rule, generally, power changeovers certainly could accompany such an inspection. Too, on the Milwaukee, the operation of electric power generally always resulted in faster transit times than diesel-electric operation for a variety of reasons.

Best regards, Michael Sol

[Anonymous]

Hi Alan, actually DC is better over long distances. I don't know where the idea comes from, but it is only a truism that AC is a better means of transporting high voltage power. It's previous advantage was only in the ease of conversion to different voltages, but in fact, DC is a superior form of long distance, high voltage electric power transmission. As technology has reduced the cost of converting DC power, its advantages have increased to the point where high voltage DC is now the preferred means of long distance electric power transmission.


I am not to sure on that. In Britain 1500 volts was the standard before the Second World War, with the exeption of the Southern Railway, but the railways did not have the money for large scale electrification. When the money became available Post War in the 1950's it was decided to electrify at 25kv industrial frequency. For new electrification since the 1950's 25kv has been the way the go. Other voltages have been extensions to existing systems. If the difference is so small way have new projects all been high voltage AC. In addition i dont now of good loco standard motor that can handle much over 1200 volts so how would high voltage DC be used in motors.

[dehusman]

I doubt whether any railroads have active electrification plans. It is incredibly expensive initially. It requires huge permanent physical plant investments and it requires new locomotives that are restricted to just one portion of the railroad. There are very few locomotive savings because you still need virtually the same number of engines to haul the trains away from the electrified portion and you have the added delay of changing engines at the boundry point.

Bottom line is the costs are greater to electrify than the savings in fuel.

Dave H.

[RhB_HJ]

QUOTE: Originally posted by mark_in_utah

I'm not an expert on electricfication, but it appears to be used the most where you have lightly loaded trains running on a frequent basis, such as commuter rail and light rail systems. This is probably due to the limitations of an overhead catenary.

The light rail system in Salt Lkae uses a 700 VDC optimum voltage. This of course floats around due to a wide assortment of things. If we assume 700 VDC, we get a few numbers that can be scary:

A 4400 hp locomotive will consume roughly 750 watts X 4400 hp = 3.3 megawatts, or 3,300,000 / 700 volts = 4700 amps!!!!!! Even if by chance the system voltage is kicked up to 2800 volts, you're still looking at close to 1200 amps.

Not many wires can carry this current. Imagine if you have multiple engines pulling a coal drag..... Get the idea? You also have a substantial voltage drop along the wire, so you have to space the substations (DC power supplies) fairly close along the route.

You'd have to run a LOT of freight to pay for such a system.

Mark in Utah

Hi there,

I was born and grew up in Switzerland aka the Land of Electric Railway Pioneering - never mind chocolate, cheese and yodeling! [;)][:D]

OK to electrify with a return on your money it is best to do that with high-voltage i.e. Austria, Germany and Switzerland at 15kV 16.666 cycle. It helps if you're running relatively short trains at relatively high speeds and can keep the differential between freight speed and passenger speed to a minimum or get the freight on separate tracks.
The propulsion technology that is being used in modern AC engines has been around since 1972 - at least that was when I was trained on that technology albeit for a differnt application - but at that time lacked the sophistication that comes with the modern computers.
Using that technology in conjunction with recuperative braking makes for very efficient energy use.
BTW the catenary is not really a limiting factor in modern electrification - think AC! - modern electric engines are in the 10'000HP+ range, frequently run in MU and have tremendous acceleration. All criteria which will tax the catenary and yet are standard conditions on modern electric lines.

Of course it really helps to have hydro-electric generating capacity to feed the catenary.
The reason the Swiss electrified in a big way?? WW1 - and to some extent WW2 - with severe coal shortages (all of it needed to be imported!), in short there have been other energy crises, but people seem to forget. [;)][:)]

[MichaelSol]

QUOTE: Originally posted by arbfbe

The a.c. vs d.c. argument is really sort of a bugabo anyway. AC current travels long distances better than DC but DC has always been easier to control at the locomotive.

Hi Alan, actually DC is better over long distances. I don't know where the idea comes from, but it is only a truism that AC is a better means of transporting high voltage power. It's previous advantage was only in the ease of conversion to different voltages, but in fact, DC is a superior form of long distance, high voltage electric power transmission. As technology has reduced the cost of converting DC power, its advantages have increased to the point where high voltage DC is now the preferred means of long distance electric power transmission.

Best regards, Michael Sol

[Anonymous]

I understand the Lake Powell and Black Mesa, a landlocked RR, uses 50,000 volts (?), hauls very heavy coal trains at a moderate speed.

With that kind of voltage, does it have to be AC? 'Cuz if AC motors are getting more efficient the way AC diesel-electrics are, that would be one more reason to prefer AC.