The fuel efficiency of trains

[MillCreek]

I was just reading an article in today's WSJ about the reopening of short spur rail lines.  A line in the article caught my eye:

In the past 30 years, the number of short line railroads has grown from about 70 to about 550, said David Whorton, a spokesman for the American Short Line and Regional Railroad Association

Increased fuel costs and congested highways have made rail shipping more attractive. "A railroad can move a carload carrying three to four trucks worth of goods 300 miles on a gallon of diesel," Whorton said.

I know pretty much nothing about railroading, but that is some impressive fuel efficiency. 

[brimic]

There were a lot of commercials on the radio about a year ago claiming that freight trains delivered 500 tons 500 miles on a gallon of Diesel.
I always thought they were using some sort of funny math, but I never looked into it.

[brimic]

http://www.csx.com/index.cfm/about-csx/projects-and-partnerships/fuel-efficiency/
Looks like their fuel efficiency is in different units than we are accustoimed to.

"Moving freight by rail is 3 times more fuel efficient than moving freight on the highway. Trains can move a ton of freight nearly 500 miles on a single gallon of fuel. Efficient use of fuel means fewer greenhouse gas emissions for our planet.

Fuel efficiency for trains is measured in terms of ton-miles, because the length and weight of trains varies greatly. We are constantly working to improve our efficiency. In 2009, CSX trains averaged 468 miles per gallon per ton. (Learn more at the American Association of Railroads’ website, www.aar.org .)

Here is the formula for our 2009 fuel efficiency rating: (From the 2009 R-1 Report)

Schedule 750, Fuel consumed (freight + switching) = 446,999,921 gallons
Schedule 755, line 110, Revenue Ton-Miles = 209,248,946,000 RTM
RTM per gallon = (209,248,946,000 RTM / 446,999,921 gals) = 468 RTM/gal"

I'm betting that is with optimal loading, ie a lot more than 1 ton of freight or a lot more than 500 tons for their 500 ton/mile/gal figure.
I'm also guessing that it means for distances over a lot more than a mile too.

I'm betting my car will nearly double its gas milage if I only count the time its going 45 miles per hour.

[MillCreek]

Huh.  I wonder if ton-miles is a common metric used in other types of shipping, like trucks, ships or aircraft.  Or is there another universally-accepted metric.  That would certainly make it easy to compare efficiency of freight handling using different media.  

Of course, all of this ignores capital costs of the vehicle and infrastructure costs, but it would be interesting nonetheless.  I read something years back on the 'physics of transportation' in which trains, by using polished metal wheels on polished metal rails, were amongst the most efficient in turning a unit of energy into a unit of work, once you got up to speed.  It made me think that if we ever get maglev trains running in an underground subway in a vacuum, perhaps all they need is a hearty push at the beginning, and then they can just coast.

[RevDisk]

I know pretty much nothing about railroading, but that is some impressive fuel efficiency. 

That is why I own CSX stock, and will continue to obtain more railroad stock. Railroads will not become obsolete anytime soon. It's not miraculous fuel efficiency, as you noted with capital/infrastructure costs, but it's pretty good.

It's even better in the flat lands. The fuel efficiency drops quite a bit when you start tossing "heavy" grades into the mix. Gravity sucks when you're accelerating hundreds of tons uphill. 

[MillCreek]

I know enough about trains to know about the diesel engines driving electric generators to power the electrical motors that power the drive wheels.  In an attempt to cheat some on the laws of thermodynamics on the downhill, locomotives don't have regenerative brakes, do they?

[Boomhauer]

In an attempt to cheat some on the laws of thermodynamics on the downhill, locomotives don't have regenerative brakes

They use dynamic braking but not regenerative braking in most diesel electrics. Some electric trains use regenerative braking.

[Tallpine]

In 2009, CSX trains averaged 468 miles per gallon per ton.

For a 40 ton / 80,000 lb truck that figures out to 11.7 mpg.

About twice the mpg of the truck 

[RevDisk]

I know enough about trains to know about the diesel engines driving electric generators to power the electrical motors that power the drive wheels.  In an attempt to cheat some on the laws of thermodynamics on the downhill, locomotives don't have regenerative brakes, do they?

AFAIK, for big trains no and for subway ish trains yes.

Normal trains = Electrically propelled locomotives = diesel-electric or gas turbine-electric locomotives
Subway ish trains or commuter trains = electric locomotives

I know it's a big fad to use regenerative brakes on electric locomotives, but for electrically propelled locomotives, it's not. Random guess is electrically propelled locomotives don't have much onboard electric storage capacity.  Electric locomotives can (usually) feed back the electricity straight to their power system. I'll be honest, I have not talked to any engineers specifically to find out why.

[MillCreek]

So diesel-electric or turbine-electric locomotives have the generators power the electric motor drive wheels directly?  There is not a big bank of batteries in the back of the locomotive? 

[Boomhauer]

diesel-electric or gas turbine-electric locomotives

Gasturbines are not common in the locomotive world. Really haven't moved much past the experimental/prototype stage despite being around since shortly after WWII.

So diesel-electric or turbine-electric locomotives have the generators power the electric motor drive wheels directly?

Yep.

[RevDisk]

So diesel-electric or turbine-electric locomotives have the generators power the electric motor drive wheels directly?  There is not a big bank of batteries in the back of the locomotive? 

I stand corrected. GE Transportation does (maybe?) make a "hybrid" train, which is just a rechargeable energy storage system (fancy term for batteries and some electronics), in their GE Evolution Series.

http://www.getransportation.com/rail/rail-products/locomotives/hybrid-locomotive.html

I have no idea what the current production state is. 

So, exists, but is not apparently standard.

[Jamie B]

The key is what they actually charge their customers.
There is also the trucking cost to and from the terminal on each end of the journey.
I would just about bet that total rail cost is slightly more than trucking.
I have not heard of a rash of trucking business being lost to rail delivery in this area.

[Tallpine]

The key is what they actually charge their customers.
There is also the trucking cost to and from the terminal on each end of the journey.
I would just about bet that total rail cost is slightly more than trucking.
I have not heard of a rash of trucking business being lost to rail delivery in this area.

The railroad doesn't deliver to your doorstep 

[RevDisk]

The key is what they actually charge their customers.
There is also the trucking cost to and from the terminal on each end of the journey.
I would just about bet that total rail cost is slightly more than trucking.
I have not heard of a rash of trucking business being lost to rail delivery in this area.

Depends on what you're hauling and where

[birdman]

So diesel-electric or turbine-electric locomotives have the generators power the electric motor drive wheels directly?  There is not a big bank of batteries in the back of the locomotive? 

A 100 car freight train (roughly 10 MILLION kilograms) traveling at 60 mph has roughly 3 gigajoules of kinetic energy (think 1200-1500lbs of C-4), or a million watt-hours.  That is 50-100 tons of lithium ion batteries (costing several million dollars)

A 1000 ft descent or rise would require the storage of nearly ten times that amount.

True hybrids aren't really practical with trains, for the same reasons it's not really practical with ships, they are too heavy.
The light hybrids being investigated use storage for smoothing of power output, not sustained acceleration/regenerative braking.

[lupinus]

The key is what they actually charge their customers.
There is also the trucking cost to and from the terminal on each end of the journey.
I would just about bet that total rail cost is slightly more than trucking.
I have not heard of a rash of trucking business being lost to rail delivery in this area.

Like anything else, there are conditions where it is cheaper and conditions where it is more expensive. Generally it's cheaper for heavier loads that are coming very long distances. Short distances, or in some cases lighter loads or LTL's, are cheaper to truck. For anything LTL it's also going through a terminal anyway, just a trucking terminal rather then a rail one. Trucking it is faster though if you needed it yesterday.

Depending on how a container is packed in the far east (either full of stuff for my DC, or a mixed bag of smaller orders destined for multiple DC's) will depend what's cheapest. If it's a container full of stuff destined for my warehouse in SC it is cheaper for the boat to sail around and into the port of Savannah, where final delivery is then made to me in SC. But the mixed bags that go to our consolidation point in Oakland CA (they'll unload multiple containers, segregate the product, and then build full containers for shipping to the individual DC's) come to us via rail into Atlanta. It's MUCH cheaper per load to load it onto the rail then it would be to truck it. The only one's that are trucked are the ones with freight that needed to be delivered yesterday. Corporate transportation pays the bills so I don't have the exact numbers, but depending on weight trucking it the whole way is upwards of 2-3x as expensive. That includes the terminal to destination cost, which is less then some of our vendors are paying to ship less product the same or shorter distances.

Also vendors that ship us full (or pretty darn near it) trucks from CA or thereabouts are increasingly using rail service. Especially when fuel prices are up, rail is simply a LOT cheaper for heavy loads going long distances.

[RoadKingLarry]

And then there  are the tank cars

[Gewehr98]

Dynamic braking = electric traction motors in axles of locomotive switch to generator mode, and send current into banks of huge air-cooled resistors situated in upper rear portion of locomotive.  Those huge cooling fans and vents back there aren't just for the big diesel engine. 

MU (Multiple Unit) connections between locomotives allow the engineer in the lead locomotive to control the throttle and braking functions of every power unit in the consist, regardless of the type, age and manufacture of diesel-electric locomotive.  That's pretty neat.

What really revolutionized freight rail was the railcar and intermodal method of putting road-mobile trailers and cargo containers on special flatcars, allowing semi tractors to finish that short hop from the railroad terminus to final destination.  That did a fair bit in reducing shipping fuel costs for what would otherwise be a cross-country Great Plains truck ride on Interstates 70/80/90.

[just Warren]

It's interesting, that the premise of the Atlas Shrugged movie was that rail travel had become more competitive due to increasing costs. And here we are with an article saying exactly that.

I'm not making any kind of deep statement here just reflecting on the oddness of it especially since I read in numerous places critics mocking movie because there was now way of rail being competitive again to the point more track was being built. 

All that said, I know the "to your front door" aspect was solved in many places. Central Manufacturing District in Chicago had their entire area set up to facilitate the use of rail cars (not much detail at the link, though).  And where I grew up there was an industrial park where almost every building had a loading dock that at some point had rails going to it. However most of the rails were gone by my time, though there were a few buildings that still got regular service from rail cars. I assume how it worked would be the needed  rail cars would be detached from the train and then taken to the proper building by a much smaller engine of some sort. Which matches up with what a fellow told me once about his job at either the Port of Long Beach or San Pedro where all he did was move rail cars about. And while he didn't go into to details it would make no sense to use a full-sized engine just to move single cars around.

So for maximum efficiency companies need to cluster together. If you can build near a port and have easy access to highways and a nearby airport you would have a major advantage in controlling shipping costs.

[MechAg94]

A lot of the chemical plants and ports down here have rail spurs so you might say they do deliver to your front door if you ship and receive enough tonnage.  Some plants my company has have rail connections and fill rail cars with liquid nitrogen and liquid argon to ship across the country.  A lot of plants ship and receive raw materials that way.

I imagine the fuel efficiency of train transport goes up considerably as the tonnage being transported goes up.  Rail cars are able to ship much larger quantities of material.

[RoadKingLarry]

If you can come up with something like this you've got it made.

http://www.tulsaport.com/

[MillCreek]

The ports of Tacoma and Seattle have huge truck/rail terminals right at the container docks.  The rails connect either to the north/south lines down the coast or the east/west lines across the mountains to the center of the country.  In south King/north Pierce counties, there are enormous complexes of distribution centers and some manufacturing that are served by rail from Seattle or Tacoma, including a regional GSA complex that handles government and military rail freight.  And of course, we have quite the amount of abandoned track that was formerly used to ship logs from the mountains down to the ports.

Probably the biggest rail boondoggle in this area was the building of a special dock in Everett and one of the steepest railroad spur grades in the country going up to the Everett Boeing plant.  This cost millions of dollars, most of which was paid by the state, county and city as an incentive to keep Boeing in Everett.  The plan was to use ships to transport sections of the 787 that were built in Asia.  They would be offloaded at the dock and put on a special railroad for transport up the hill to Boeing.  As the scope of the 787 manufacturing outsourcing debacle became clear, Boeing converted a couple of 747s to fly the parts in from Asia and Europe.  The new dock and rail spur have been used a handful of times. 

[lupinus]

A lot of huge commercial food producers (commercial bakeries, soda producers, etc.) also have rail lines coming in. Sugar, flour, corn or other syrups, grains, and any other big heavy bulk ingredients that they go through load after load of are more economical to move by train then truck, provided it's practical to place the plant near a rail line.

[roo_ster]

It's interesting, that the premise of the Atlas Shrugged movie was that rail travel had become more competitive due to increasing costs. And here we are with an article saying exactly that.

I'm not making any kind of deep statement here just reflecting on the oddness of it especially since I read in numerous places critics mocking movie because there was now way of rail being competitive again to the point more track was being built.

Atlas Shrugged seems to be a "how-to" manual for the statist set.