schlimm Not really sure, but I think I read that Diesel fuel back in the 50's was cheaper than gasoline, so maybe it would have been relatively cheaper in your calculations than now.
Not really sure, but I think I read that Diesel fuel back in the 50's was cheaper than gasoline, so maybe it would have been relatively cheaper in your calculations than now.
The story back in the "Steam-Diesel Transition Era" was that oil was being discovered/developed in Saudi and the US hadn't reached it's 1970 Hubbert Peak, and the United Mine Workers were flexing their muscles with regard to the mine workers getting better pay for the dirty dangerous work they do. Oil was particularly cheap compared to now, and it seems with the low price of oil and the much higher thermal efficiency of Diesel engines, Diesel locomotives had a clear fuel cost advantage over steam.
At the time of the ACE 3000 project -- what was that, mid '70's in response to the 70's Oil Embargo and Middle East tensions -- I believe that a mid teens thermal efficient coal burning steam locomotive had a clear fuel cost advantage over a Diesel locomotive. Even a 5 percent efficient steam engine (the ACE people tested a Northern) had a slight fuel cost savings over Diesel at that time.
Today, the price of coal is increasing along with many other things, but the price of oil in inflation-adjusted terms is not too far off from conditions in the 1970's -- early '80's.
The other thing to remember about the ACE 3000 project is that when was this, early '70's, and when did Norfolk and Western drop the fire of the last mainline steamer, 1960? Yes the railroads were thoroughly Dieselized and the thought of bringing coal-fired steam back -- think of Don Oltmann's shop foreman thinking the best thing to do with a locomotive boiler was to fill it with cement so it could not be put in service and have a boiler explosion accident. But there were probably enough old-timers around the railroads to make this steam thing work, if that was the direction.
Today, we are 40 years away from the ACE 3000, 50 years since the end of steam on N&W, 60 years since when the railroads pretty much pulled the plug on steam. During the steam-Diesel transition, the railroads were "investing" in a hodge podge of 1st Generation Diesels with various levels of maintenance expense. By the ACE 3000, they were competing with the SD-40 and later SD-40-2, perhaps the most "bullet proof" locomotives known to mankind, steam or Diesel.
Ah steam! The dream doesn't die.
If GM "killed the electric car", what am I doing standing next to an EV-1, a half a block from the WSOR tracks?
C&NW, CA&E, MILW, CGW and IC fan
OK everyone, let's chalk this up to "The more I learn, the more I find out how ignorant I are!" The only place I could find definite bulk pricing information, with somewhat current figures, was the U.S. Energy Information Administration's website. The information I chose from there (which may or may not be the proper choices) was Central Appalachia coal, 12,500 BTU's per lb, $71.15 per short ton for a total of 351,370 BTU's per dollar (I know, PRB coal is cheaper, but for goodness sakes it has the BTU content of peat...can you say Wooten Firebox?). For diesel fuel, I chose low sulfer no. 2 that was sold directly to non-highway end users for $2.31 per gallon for a total of 63636 BTU's per dollar. These were based on late 2010 prices. At the previously assumed effieciencies of 10% steam/coal vs 25% diesel, we would get 35137 BTU's of work per dollar out of coal vs 15909 BTU's of work per dollar out of diesel, over 2:1 in favor of steam... but hold of the celebrations for a moment. For some reason, the government calculates the price of diesel as an average that includes transportation. No such luck on the spot price of coal - as far as I can tell - so we don't know if transport costs would increase the price of coal so much as to tip the scales to diesel. For what it is worth, diesel has 20137 BTU's per pound vs coal's 12500 BTU's per pound, which would indicate (based on weight) that coal might cost 61% more to ship than diesel. This would not even reflect any difference in price based on ease of handling of diesel vs. coal. I have no way of calculating a shipping cost for either coal or diesel, so I can't make an apple to apple comparison. No doubt about it, the professional bean counters at the railroad would know the exact price of each commodity delivered on location and would be able to make a better comparison than the barnyard guestimate that I have scribbled out. I suspect that with fuel transport and locomotive maintenance costs figured in, the diesel would still be the economic winner in today's market... otherwise we would have the ACE3000 polishing the rails!
And I never did find any definite prices for coal and diesel from the transition era...
My brain hurts... does anybody have any aspirin? - James
selector Is the price of $15/50 lbs of decent coal what it really costs today? How would the numbers have crunched in 1946? Was the price ratio roughly the same? Crandell
Is the price of $15/50 lbs of decent coal what it really costs today? How would the numbers have crunched in 1946? Was the price ratio roughly the same?
Crandell
The price I quoted is indeed retail for small quantities intended for the live steamer or blacksmith. Certainly, a railroad would negotiate a much cheaper price for large amounts of coal, just the same as they negotiate a much cheaper price for diesel fuel than the price per gallon that I quoted (from our local filling station - including road taxes). I was just using some easily attainable retail numbers as a reference. To get an accurate comparison in today's market, we would need to know what price per gallon large railroads have recently contracted diesel fuel for as well as a bulk price per ton of coal, perhaps from a large utility. I'll have to do some more research to see if those numbers are readily available, as well as numbers from the transition era... when I get some free time later tonight!
- James
ndbprr Since the last steam engine is early 50s technology thereis no "current" comparison. Only speculation.
Since the last steam engine is early 50s technology thereis no "current" comparison. Only speculation.
Speculation, yes, along with a detailed design study from the last living "great steam engine designer" David Wardale http://www.5at.co.uk/. The claim is that one could squeeze out 14 percent thermal efficiency by careful design of a "conventiona Stephenson-pattern" non-condensing steam locomotive.
As to the high coal price, if you are buying coal in small lots for live steam operations, I guess that is what you would have to pay. Even with the runnup in coal prices, however, a major user of coal would work out some supply arrangement and much lower prices.
To put a finer point on cost, let's take a look at a coal burning steam engine vs. an infernal combustion diesel locomotive. I am using a retail cost of $15 for 50lbs of coal and $3.30 for a gallon of diesel. The coal I priced has a BTU content of 14373 BTU's / lb, so we get 47190 BTU's per dollar spent on coal. Diesel has 147,000 BTU's per gallon, so we get 44545 BTU's per dollar spent on diesel. Using efficiencies of 10% for steam and 25% for diesel, we get 4790 BTU's of work for every dollar spent on steam locomotives vs. 11136 BTU's of work for every dollar spent on diesel locomotives. Add in labor and maintenance costs, and it's easy to see why railroads were eager to dieselize. Modern technology could probably replace the fireman, as well as easing some of the maintenance requirements. However, the efficiency of the steamer would have to be raised significantly to make it cost effective against the diesel locomotive.
Yes, economics doomed the steam locomotive.
I still think they are great!
It's sad that Norfolk Southern destroyed their excellent steam excursion program in 1994. It was a truly a flawed and short-sighted decision to save a minor amount of money and lose a tremendous amount of publicity and good will. Shame on you Norfolk Southern Management!
Scraping some random cites from Albert Churella's "From Steam to Diesel" (1998, Princeton University Press):
By the late 1930s, RR executives said diesel could reduce fuel costs for RRs by 75%. Diesels could run further between refuelings, did not need water (a serious concern for railroads like the SP and Santa Fe in Arizona and New Mexico), and one tank car of diesel fuel was said to pack the equivalent of eight hopper cars of coal, thus reducing transport costs. One railroad executive said the cost of new fueling facilities could be paid for just from eliminating the hopper car fleet needed to haul locomotive fuel.
Horsepower and tractive effort: at ten mph, a 600-hp diesel switcher provided more actual tractive effort than a 2,000-hp steam locomotive, while a 6,000-hp steam locomotive produced 135,000 lbs T.E compared to a 6,000-hp diesel packed 230,000 lbs. T.E. at the same speed. This led to the adage that a steamer could move a train at speed that it couldn't start, while a diesel could start a train it couldn't hustle.
I've heard various figures over the years cited for the outright thermal efficiency of steam and diesel locomotives. Suffice it to say that 8-10% for steam is probably realistic, with a "pie in the sky" (or "what are you smoking?") figure of 20-25% sometimes cited. Diesel, on the other hand, would muster 20% on a bad day, with 30-45% being equivalent "wishful thinking". So even in worse case scenarios, you're looking at double the output per BTU for diesel.
Using statistics collected during the early 1940's, the Santa Fe Railroad measured the efficiency of their fleet of steam locomotives in comparison with the FT units that they were just putting into service in significant numbers. They determined that the cost of a ton of oil fuel used in steam engines was $ 5.04 and yeilded 20.37 train miles system wide on average. Diesel fuel cost $ 11.61 but produced 133.13 train miles per ton. In effect, diesels ran six times as far as steamers utilizing fuel that cost only twice as much. This was due to the much better thermal efficiency of diesel engines compared to steam. Persumably the trains used as a milage standard were 4000 ton freight consists which was the normal tannage l at that time.
It would have to be a very well designed and built steam locomotive to get more than 7 or 8% efficiency. Very little of the energy prouced from combustion is turned into mechanical force, most of it goes up the stack. Even condensing steam engines, such as those used in power plants and on ships, have to release a majority of the heat energy in the condensing process.
Internal combustion is somewhat more efficient, but still more energy is thrown off as heat (through the radiators) than actually turns the wheels.
John
If everybody is thinking alike, then nobody is really thinking.
http://photobucket.com/tandarailroad/
There are three things working against the efficiency of a steam locomotive. One is that it is a non-condensing cycle. Condensing is not very practical in a steam locomotive as you are not carrying a cooling pond with you, and the few instances of condensing locomotives (South Africa had some) had limited efficiency gain owing to the inefficiences of an air cooled condensor. A second is the low boiler pressure, and that in part is tied to the non-condensing cycle. You are using water that hasn't been distilled and purified, a necessity for the very high boiler pressures used in modern steam electric power plants. A third is until the very end of steam when some people (Chapelon, Porta and others) started looking at steam engines on a scientific basis, there are a variety of combustion losses, heat losses, and pressure-drop losses to contend with.
The figures I have heard are around 5 percent for the sort of Northerns towards the latter days of steam, maybe 10 percent for Chapelon's compounds where he paid a lot of attention to minimizing the losses I mention above, with maybe 16-20 percent being a theoretical upper bound for the kind of boiler pressures and for the non-condensing cycle. Electric power generation runs in the 30-40 percent range, using condensing cycles, insane boiler pressures, high superheat, and compound expansion in turbines running at near steady-state conditions.
The thing about the steam engine and dwelling on the thermal efficiency, it was a good system back in the day. The cost of labor can be thought of negatively as men wearing out their backs shoveling coal and men getting black lung or worse working in mines. Or the cost of labor could be thought of as men having paying jobs to support familes. However you view it, the system was that you dug what were otherwise worthless rocks out of the ground (lumps of coal), fed them into steam engine boilers, and carried people and goods around. It was an effective system as it carried a lot of people and goods around that would have otherwise stayed put. The moving of people and more importantly of goods, especially food, was transformative in way that is now hard to imagine.
The other thing about the thermal efficiency is that according to Porta, if you optimized the design of the conventional steam locomotive (what he called Generation 0) to produce Generation 1 -- pretty much the same boiler pressure and non-condensing, just better insulation, steam passages, and valve events -- you could at least double the efficiency, in the process cutting water and coal consumption in half. That may have been enough to keep steam around for another 10-20 years, but after that, hey, they have replaced all of the steam powerplants on boats and ships with Diesels as a labor saving measure if nothing else.
For the BTU used to operate one, how efficient is a steam engine. And I'm talking about with the most current technology.
Modeling the "Fargo Area Rapid Transit" in O scale 3 rail.
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