I just read in the March 2015 issue where Amtrak will be able to add an extra passener car on the AutoTrain due to replacing older bulbs with LED’s. I started wondering, just how much power does a passenger car require? I take it all the hotel power is supplied by the 2nd engine we usually see attached? I never gave much thought about the actual power supply to those cars until now. When I started thinking about it I soon realized I didn’t know a whole lot about it. Thanks a lot.
Back when Amtrak was getting F40s with 800kW HEP I think they claimed that was enough for 18 cars. (Obvious question: at what outside temperature?) But yeah (in those days at least) all the HEP came from one unit, so if you wanted to run an 18-car train… And supposedly Amtrak was known to run specials to Seahawks games with 18 Superliners (early 1980s?).
This article on the Trains website may prove insightful:
http://trn.trains.com/railroads/abcs-of-railroading/2006/05/head-end-power
Keep in mind that only one locomotive can supply HEP to a train.
Thanks for the reply. Appreciated.
Ty, thanks for the interesting reply. Enjoyed the link.
This article has left out the ACS-64 which has dual 1000 KW inverters.
What is more important is what is the max HEP draw of each type of car. + LED lighting or not.
Amfleet -1, -2 coaches if different.
Same diner lite, Lounge, etc.
Superliners -1, -2 same + Diners when under fulload.
Viewliner -1, -2
Horizon
Baggage cars both Heritage and new V-2s
PVs
Any others ?
Then you can add up load and determine load for each type loco.
Simple? === Yeah.
Our Stadco gensets are good for about 150 amps (480V 3 phase). Someone else can figure out how many kilowatts that is. I can handle DC and single phase AC. Three phase is out of my range of knowledge.
When powering up our trains in cold weather, we have to sequence the cars so they aren’t all calling for full heat at the same time.
I’m pretty sure one genset will keep our entire Polar Express train (12 cars) at 60 degrees, lights off, plus two Kim HotStarts, in freezing weather. We normally split the train into two sections for the actual runs (~70 degrees, plus lights, minus the hotstarts).
Were we not on our winter hiatus, I could probably do a test of a car to see what ours draw. Of course, we aren’t running a kitchen, either.
Larry,
I get about 125kW for unity power factor and 100kW at 0.8 power factor. Sticking my finger in the air (and not in a light socket), call it 120kW, so about 10kW per car.
- Erik
And heat is a huge factor for us in that number - we’ve been known to run an entire occupied train on one genset, but it isn’t pretty and usually involves some rotating of which cars are getting heat so no one gets too cool.
A/C draws a pretty good amount, too.
I really appreciate the responces I received. Boy, needless to say I sure learned a lot. And that is a good thing.
I used to know this…
Here’s what I think I remember:
Each Amfleet car has two 8 ton AC units.
A locomotive has about 10KW of heat available in the cab. (Yeah, that’s a lot!)
The business cars CR built at Reading had about 40 KW of heat in them.
The under car gen sets in the business cars were 60-80KW.
YMMV. Batteries not included. Some settling may have occurred during transit.
Used to be batteries were included – didn’t some Heritage cars run the AC off axle generators and batteries? Mmmm, toasty! And others used gobnormous amounts of trainlined steam to operate steam ejector AC? Mmmm, steamy!
Seeing all of these trucks with “reefer” units, I get to wondering why “they” went with HEP instead of giving each passenger car a diesel genset – the Santa Fe Hi-Levels did just that. The genset was in a bay over one of the trucks, and this skinny exhaust pipe went up the side of each coach to discharge near rooftop.
Because maintenance someone will reply. But what about all of those reefer trucks and reefer freight cars? That each train car is self contained gives a great deal of operational flexibility, and those trucks have these garbage can-sized fuel tanks under the reefer van that you would think keeps the reefer unit going a long time between refuelings?
Don’t know if these podded reefer units do this when they need to provide heat, say, for a lading that you cannot let go below freezing such as fresh produce. But could you not build a much more efficient heating mode by supplementing heat-pump operation of the reefer unit with heat from the engine. The heat you get in the car comes from the engine radiator water, which is only supplemented by running the AC for defogging/defrosting your windows.
Yes, Paul, I had two not-so-good experiences with motion-generated electicity.
The first one came when I rode the combine of the Silver Meteor from Tampa to St. Petersburg in April, 1967; the car ran from St. Pete to Wildwood one day, and sat there for more than twenty hours before coming back the next day to sit overnight. The flagman apologized for the warm air in the car, explaining that it did not run enough to keep the batteries charged.
The second one came in July of 1971, when I rode in the UP’s sleeper, Pacific Castle, from Washington to St. Louis. When I woke in Ohio the morning after leaving Washington, there was no electricity in the car, for the generator had failed during the night. The next day, going to Indianapolis, I noticed that the generator had been repaired or replaced. My next two trips in that car were much better–riding from Decatur, Alabama, to Birmingham with my fiancee in 1972, who had boarded in Chicago when coming to visit me before we married, and traveling from Washington to Birmingham together in the same car, in 1989.
Paul,
I’d guess that the maintenance on the HEP equipment on the locomotive would be far less than the maintenance on individual gensets for each car. Gensets would require fuel tanks on each car, with the hassle of fueling each tank as well as an increased fire hazard. Finally, replacing a failed HEP can be done by swapping the locomotive.
A few of UP’s early “City of” trainsets were equipped with head end power for providing electric resistance heating of the cars and that was found to be more efficient than steam heat.
- Erik
There are all kinds of railroad and especially railroad passenger practices that go contrary to just about what everyone else is doing, and they need to be that way because trains are a special case, I guess.
My office at work is steam heated by a district heating plant some blocks away from the building. The steam pipes run underground between buildings. Steam heat is probably the most energy efficient and cost effective way to implement centralized heating or to heat large structures. Railroads once used it but it was regarded as a pain – leaking steam pipes, valves set the wrong way leaving cars without heat, freezing pipes, the hassle of coupling and uncoupling cars and having to call a properly qualified pipe fitter to make the steam connection, and so on.
On the other hand, using a diesel genset or an alternator tap in the locomotive to provide electricity for electric heat is wasteful of energy by a factor of 2 or 3 compared to steam heat. If the railroad industry (commuter ops and Amtrak) hadn’t given up on steam heat for the operational convenience of an electric plug over connecting steam pipes between cars, it would be this new, environmentally friendly thing for Saving the Planet.
The trucking industry could have run reefer units off the engine alternator in the truck tractor, but no, they made the reefer unit have its own engine and fuel supply. I suppose this gives them enormous operational flexibility. When you uncouple a reefer van, you don’t have to figure out how to keep the reefer unit supplied with power. You can also fuel up the reefer tank and send it intermodal without requiring the railroads to provide a freight-car version of HEP.
If you really want a centralized model, why do individual passenger cars have their own AC units? Why not have a chiller in the locomotive and trainline a chilled water supply? The AC in my office works that way.
If you really want to go green, why not power
[quote user=“Paul Milenkovic”]
There are all kinds of railroad and especially railroad passenger practices that go contrary to just about what everyone else is doing, and they need to be that way because trains are a special case, I guess.
My office at work is steam heated by a district heating plant some blocks away from the building. The steam pipes run underground between buildings. Steam heat is probably the most energy efficient and cost effective way to implement centralized heating or to heat large structures. Railroads once used it but it was regarded as a pain – leaking steam pipes, valves set the wrong way leaving cars without heat, freezing pipes, the hassle of coupling and uncoupling cars and having to call a properly qualified pipe fitter to make the steam connection, and so on.
On the other hand, using a diesel genset or an alternator tap in the locomotive to provide electricity for electric heat is wasteful of energy by a factor of 2 or 3 compared to steam heat. If the railroad industry (commuter ops and Amtrak) hadn’t given up on steam heat for the operational convenience of an electric plug over connecting steam pipes between cars, it would be this new, environmentally friendly thing for Saving the Planet.
The trucking industry could have run reefer units off the engine alternator in the truck tractor, but no, they made the reefer unit have its own engine and fuel supply. I suppose this gives them enormous operational flexibility. When you uncouple a reefer van, you don’t have to figure out how to keep the reefer unit supplied with power. You can also fuel up the reefer tank and send it intermodal without requiring the railroads to provide a freight-car version of HEP.
If you really want a centralized model, why do individual passenger cars have their own AC units? Why not have a chiller in the locomotive and trainline a chilled water supply? The AC in my office works that way.
Paul,
I’ve seen a couple of references that specifically state that back in the 1930’s, the UP found that electic resistance heating where the power was generated by a dedicated HEP diesel engine used less fuel for heating than a similar train steam heated using a Vapor-Clarkson steam generator. A couple of years earlier, the first UP streamliner attempted to use the coolant from the prime mover to heat the train, but that was found to be inadequate.
Keep in mind that the steam lines on a train are exposed to the cold air, where the steam lines to you office are routed underground. I think it would be a fair guess that the mass flow of steam in the pipes to your office buiding is at least an order of magnitude higher than what’s flowing in a train line. One of my NE professors at Cal asked facilities about how much energy (steam and electricity) Etcheverry Hall used and was quoted “about a megawatt”, which was the rated output of the Triga MkIII reactor in the building - which couldn’t be operated for more than 8 hours a day because the N16 gamma flux at the volleyball court over the reactor would be above the dose rate allowed for unrestricted access - the dose rate being on the order of what you get from cosmic rays in pplaces like Leadville.
I’m not entirely convinced that a central steam plant is the most efficient means of heating. Where natural gas or LPG is used for heating, a condensing furnace such as the Lennox pulse does a remarkably good job of getting almost all of the available heat energy from the fuel. A central steam heating may come close if the steam is run through a turbine as part of a topping cycle.
Cooling a train with cilled water would probably be less efficient than the current practice of each car having its own A/C unit - some improvement could be achieved by spraying water (preferably de-ionized) over the condensor coils.
IMHO, the biggest energy waste on a large number of passenger trains (e.g Pacific Surfliner)
Ah, I think many forget the KISS principle. (Keep It Simple Stupid) Steam heat has many issues, plumbing, freezing, water supply, and others. The early diesels had to have both fuel and water tanks. Coupling cars required connecting not just air (brake) lines but also steam lines. I know, today you have to plug the four electic cables into their sockets but that is easier than connecting a hot pipe together. And forget thawing out a frozen steam line. Electric cables don’t freeze. And water connections between cars, get real. They leak. Those picture of passenger trains of yore with the romantic clouds of steam, those were frequently leaks. Electric air conditioning is proven and relative straight forward. Three phase 480 volt 60 cycle power is an industry standard with off the shelf equipment.
Part of the problem is institutional. The mechanical dept has to maintain this stuff. They generally control the specs on the equipment. They will write specs to minimize their headaches and cost.
The transportation dept. pays for the fuel. They often have little leverage with the spec writers. Labor, not fuel, is traditionally budget line item hammered. Fuel cost isn’t something you manage day to day.
That is exactly what drove the change.
Anyone who rode early Amtrak can tell you stories about hot and cold cars as a regular feature of many trains, particularly in the northeast. HEP and Amfleet fixed all of that.