No, TOFC's aren't as good as containers. Nor are 79 mph trains as good as drags. But then, a hot shot trucker driving 90 isn't doing all that well either, nor is one hauling post holes...
And if my experience is any guide, most trucks sit around the truck stops with their engines idling, not off, in spite of the signs -- so that argument on efficiency won't wash, either.
It's real hard to beat the fundamental physics (as usual): a steel wheel on a steel rail has far less rolling resistance than a rubber tire. All else being equal, a train will be more fuel efficient than a truck. What we are looking at here in these various posts are the unequals.
jchnhtfd wrote:Oltmannd's figure of 11 to 18 loaded trailer miles per gallon is the one ... So there really isn't any comparison -- a train is anywhere from 4 to 6 times as fuel efficient as a truck.
So there really isn't any comparison -- a train is anywhere from 4 to 6 times as fuel efficient as a truck.
Depends where you're hauling the trailers. Put 100 trailers on flatcars in Denver and haul them to Omaha on a slowish schedule, and maybe you'll use a sixth the fuel you would with trucks-- or maybe not. But don't plan on doing that well on a TOFC round trip, there or anywhere else.
Didn't directly answer Ramrod's question, but: Oltmannd's figure of 11 to 18 loaded trailer miles per gallon is the one you want to go with; well documented and researched. Which you can compare to a modern over the road truck at, at most 3 to 4 trailer miles per gallon. So there really isn't any comparison -- a train is anywhere from 4 to 6 times as fuel efficient as a truck.
All else being equal.
Which it never is! A longer train of double stacks will be slightly more efficient, for instance, than a shorter one, or one which is a mix of doubles and singles (aerodynamic drag). A slower train will be somewhat more efficient than a faster one (though not as much as you might think, and the difference is much less than it is for a truck -- again, aerodynamic drag).
Newer diesels (either truck or rail) are more efficient than older ones, simply because they have much better controls for the prime movers.
snagletooth wrote: Isn't it true, thuoght, that even that new loco eat more fuel per say, ( as say, an SD70, compared to an SD40-2) that they use less using two SD70's compared to 3 SD40-2's to hual the same tonnage? Wasn't that what they sold railroads on in the 70's on the 40 series compared to the F's? "Yes, a single SD40 eats more fuel than a single F, but 4-6 F's eat more fuel than two SD40's to move the same tonnage!"?
Sorta...
On the fuel side, it's not strictly units x fuel burn rate, but the specific fuel consumption. That is, how many HP-HRs do I get out of the beast when it burns a gallon (or more properly, a pound) of fuel? This calculation works out OK on a large RR when you can also reduce the number of locomotive proportionally to the HP rating of the locomotive so that you wind up with the same HP/ton, on average, on your trains. If you wind up with more HP/ton on the average, you can negate the fuel efficiency gain by going faster.
On a small RR, you might have to look at the actual trains operated to see if you can practially reduce the number of locomotives and what the performance against the schedule would be if you did.
Reducing fleet size also reduces the amount of idle fuel consumed and maintenance/inspection costs.
-Don (Random stuff, mostly about trains - what else? http://blerfblog.blogspot.com/)
oltmannd wrote: What you're looking for is a trailer mile per gallon figure, or equivalent.Way back in 1984, we did some NJ to Chicago fuel consumption tests to generate the relationship between ton miles per gallon and train HP per ton. We were using 3 or 4 GP40-2s and/or B36-7s on trains that were in the 50-60, 89' flat car range, operating through PA. As I recall, we calculated about 15 loaded trailer miles per gallon and about 25 for empty trailers. I'll have to see if I have a copy of that report around somewhere.Today's intermodal trains are generally larger and have lower HP/ton and have lighter tare wt. equipment, so fuel economy should be a good bit better that that from our 1984 test.
What you're looking for is a trailer mile per gallon figure, or equivalent.
Way back in 1984, we did some NJ to Chicago fuel consumption tests to generate the relationship between ton miles per gallon and train HP per ton. We were using 3 or 4 GP40-2s and/or B36-7s on trains that were in the 50-60, 89' flat car range, operating through PA. As I recall, we calculated about 15 loaded trailer miles per gallon and about 25 for empty trailers. I'll have to see if I have a copy of that report around somewhere.
Today's intermodal trains are generally larger and have lower HP/ton and have lighter tare wt. equipment, so fuel economy should be a good bit better that that from our 1984 test.
Found a copy of the report:
For TV11 with three locomotives, the fuel economy was 11 loaded trailer miles per gallon, 18 for empties. For TV12M, it was 16 loaded trailer miles per gallon (train was usually close to 100% loads, so no empty trailer miles per gallon could be calculated.
Gross ton miles per gallon averaged 440 for TV 11 and 630 for TV12M (with 3 locomotives per train). HP/ton for the TV11 ranged from 2.4 to 3.5. For TV12M is was 2.0 to 2.5.
Another interesting result was that the B36-7s were 12% more efficient in generating net traction HP (electrical output of generator headed for the traction motors) than the GP40-2s.
According to the AAR, today's locomotives will move one ton, 432 miles, with one gallon of fuel. Modern locomotives have a fuel capacity between 4,000 and 5,000 gallons. That's usually good for about 1,000 miles.
We have a computer program that tracks the fuel usage. The computer estimates the miles run and calculates the fuel usage. It's remarkably accurate. But we do get a visual reading to confirm the fuel level.
Nick
Take a Ride on the Reading with the: Reading Company Technical & Historical Society http://www.readingrailroad.org/
Usually the foriegn power is at full throttle while the home units are enjoying the assist at idle.
railroadjj wrote:On the newer locomtives the lead unit can see how much fuel is on every locomotive that is MUed to it. When a train comes into a major yard like CHI, or KCK, then if the train is continuing on and needs a new crew the yard controller will usually ask how much fuel they have. If it is to low, the fueling truck will be called to refuel all motors.
On the newer locomtives the lead unit can see how much fuel is on every locomotive that is MUed to it. When a train comes into a major yard like CHI, or KCK, then if the train is continuing on and needs a new crew the yard controller will usually ask how much fuel they have. If it is to low, the fueling truck will be called to refuel all motors.
What newer locomotives have this capability to see how much fuel is on every engine in consist? I've run SD70aces, and GEVO's and haven't ran across any of these that do this. When the tower or dispatcher wants to know how much fuel we have we check it the old fashioned way and visually check gauges on each unit.
Fuel usage is figured by Gallons Per Hour(GPH) at idle and full throttle.I imagine that locomotive fuel capacities today are probably 5,000 gallons.During the 1970's locomotives such as the SD45,SD40-2,U30C,and U33C were generally 4,000 gallon.A lot depends on the RPM's of the engine at idle and max.For example,the SD40-2 had an idle RPM of 315 and max of 900 with it's 645E3 engine.Succeeding engines had less idle RPM's thru the 645E3B AND 645E3C engines,the last having a 215 RPM idle speed,but all maxed at 900.Number of cylinders will also greatly impact fuel usage.The SD45 was a fuel hog because of it's 20 cylinder engine,the SD40-2 was better with 16 cylinders.
I know there are figures out there for GPH use for different locomotives as I remember reading about the differences with the SD45 and SD40-2.I can't remember the figures,nor find them online.Maybe someone can help with this?
As for the comparison between trains and trucks.Look at the different sizes of engines between the two,the amount of tonnage pulled,then factor in grades,speed,weather,operator habits,etc.I think trains win out in all aspects.
Have a good one.
Bill B
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