Train VS truck efficiency!!

[roofeditor]

Rail vs. Truck Energy Efficiency (In Progress)


Railroad fuel efficiency has increased by 72 percent since 1980. Then, a gallon of diesel fuel moved one ton of freight an average of 235 miles. In 2001, the same amount of fuel moved one ton of freight an average of 406 miles.

UP: Rail Versus Road

COMEBACK AHEAD FOR RAILROADS They have been losing out to truckers for decades. Now they are grabbing business and making shareholders happy. With help from Congress, they should do even better. - June 17, 1991

[roofeditor]

Just for fun!!!

Union Pacific Box car is 50 feet long and 9.3 feet wide.

Our stick down solar panels are 15 inches wide and long and 216 inches long.

So we could put them 8 across and about three long. So that would be 24 panels on each box car. Our panels are 136 watts each!!!


136 watts each x 24 panels would be 3264 watts on each car.

Typical Florida train of 100 cars??? 3265 times 100 = 326,400 watts!

For those of you from Rio Linda thats about 500 HP!!!


Well I don't think 500 hp would push a train all that much.

So Al gore saying switch from oil/gas/diesel directly to electric would not work here at all. The cost of our panels BTW would be 1.6 million dollars!

Solar has it's place but not running a train.

Want to laugh a small Los Angles class reactor would fit in one engine.

A 100 megawatt unit is 134,102 HP. I think that might be enough to push a train along!!!!

10 years on fill ups!

100 megawatts

[clamgulch]

The newer reactors are designed (supposedly) to be able to last their full 30 year life without refueling.

Box cars- that's an interesting idea. True, 500 hp won't push a loaded train car up steep hills very fast, but it would darned sure help a significant amount. It doesn't have to be "all or nothing." I wonder how much the price would drop if there were a dedicated plant manufacturing solar panels for ever single box car in the nation. Also, the beauty of solar panels is they don't wear out- so if they were built robustly enough, they could be transplanted to new cars when the old cars wear out.- or sold for other applications, like housing perhaps?

[AK_Gandy]

Originally Posted by roofeditor

COMEBACK AHEAD FOR RAILROADS They have been losing out to truckers for decades. Now they are grabbing business and making shareholders happy. With help from Congress, they should do even better. - June 17, 1991

1991?!

That is one old article.

I can tell you though that the railroad bidness has been doing very, very well in the last 4-5 years.

[THEBUNDO]

Originally Posted by clamgulch

The newer reactors are designed (supposedly) to be able to last their full 30 year life without refueling.

Box cars- that's an interesting idea. True, 500 hp won't push a loaded train car up steep hills very fast, but it would darned sure help a significant amount. It doesn't have to be "all or nothing." I wonder how much the price would drop if there were a dedicated plant manufacturing solar panels for ever single box car in the nation. Also, the beauty of solar panels is they don't wear out- so if they were built robustly enough, they could be transplanted to new cars when the old cars wear out.- or sold for other applications, like housing perhaps?

The 500 HP was the total for a 100 car train, not per car

[checkthisout]

Originally Posted by clamgulch

The newer reactors are designed (supposedly) to be able to last their full 30 year life without refueling.

Box cars- that's an interesting idea. True, 500 hp won't push a loaded train car up steep hills very fast, but it would darned sure help a significant amount. It doesn't have to be "all or nothing." I wonder how much the price would drop if there were a dedicated plant manufacturing solar panels for ever single box car in the nation. Also, the beauty of solar panels is they don't wear out- so if they were built robustly enough, they could be transplanted to new cars when the old cars wear out.- or sold for other applications, like housing perhaps?

I think roof was just having some fun. Dirt and Vandalism would be a huge problem if we put solar panels on box cars.

I like the idea of partial electrification of the railway better.

Use a smaller engine and use electricity to boost the train where necessary.

There was also a very good snippet posted some time ago where the train puts power back into the grid when dynamically braking on long inclines thus helping another train that is climbing instead putting it into the heat sinks where it's simply wasted.

[NBhunter80]

A 100 megawatt unit is 134,102 HP. I think that might be enough to push a train along!!!!

10 years on fill ups!

100 megawatts

The numbers do sound great; however, installing a nuclear reactor on a train would not be as easy as installing one in a sub. First problem, the sub weighs 6000 tonnes. The only reason this is possible in a sub is because of the buoyancy of water supporting the weight of the vessel. Therefor all the power can propel the sub with very little being wasted just trying to fight friction and gravity. This is not the case with a train...it must fight against gravity and friction to move itself. If you do the math, just the engine itself weighs 6000 tonnes = 6,000,000 kg, therefor on a 10 degree hill to move the engine uphill would require 6,000,000kg (0.17365)(9.18) or ~ 9.5 million N of force. Say the hill was 1km long... then you need to do 9,500,000N(1000m), or 9.5 billion Joules of work to move the train up that hill. Say you wanted to do this 1km hill in 1 minute (meaning 60km per hour or ~ 37mph), the power calculation would be 9,500,000,000J/60sec = 158 000 000W or 158 megawatt. Therefor just to fight Gravity on the engine and move it up this hill the train would use 158 megawatt of power. Keep in mind this is for an unloaded train!!! no cars at all, and this does not include the power required to fight friction and inertia. I'm sure people have thought of this possibility before;however, nuclear powered trains are not possible with the current technology. Another downfall is the cost. A nuclear reactor can cost several billion dollars to build and maintain. You would have to haul an aweful lot of cargo to make back that investment.

[roofeditor]

Originally Posted by NBhunter80

The numbers do sound great; however, installing a nuclear reactor on a train would not be as easy as installing one in a sub. First problem, the sub weighs 6000 tonnes. The only reason this is possible in a sub is because of the buoyancy of water supporting the weight of the vessel. Therefor all the power can propel the sub with very little being wasted just trying to fight friction and gravity. This is not the case with a train...it must fight against gravity and friction to move itself. If you do the math, just the engine itself weighs 6000 tonnes = 6,000,000 kg, therefor on a 10 degree hill to move the engine uphill would require 6,000,000kg (0.17365)(9.18) or ~ 9.5 million N of force. Say the hill was 1km long... then you need to do 9,500,000N(1000m), or 9.5 billion Joules of work to move the train up that hill. Say you wanted to do this 1km hill in 1 minute (meaning 60km per hour or ~ 37mph), the power calculation would be 9,500,000,000J/60sec = 158 000 000W or 158 megawatt. Therefor just to fight Gravity on the engine and move it up this hill the train would use 158 megawatt of power. Keep in mind this is for an unloaded train!!! no cars at all, and this does not include the power required to fight friction and inertia. I'm sure people have thought of this possibility before;however, nuclear powered trains are not possible with the current technology. Another downfall is the cost. A nuclear reactor can cost several billion dollars to build and maintain. You would have to haul an aweful lot of cargo to make back that investment.

By that calculation a train with 4 engines at 5,000 hp each could not climb much of a grade!

I was joking on puting a reactor in a train. My early career after MIT was at The Electric Boat Company in New London. Point I was making is that no matter what Al Gore says Trains will be powered by diesels for a long time.....possibly bio-diesel.

[roofeditor]

[quote=AK_Gandy;1601115]1991?!

That is one old article.

I can tell you though that the

Even back then Trains made more sense, with $4-5 diesel fuel trains must be part of the energy plan!

[NBhunter80]

By that calculation a train with 4 engines at 5,000 hp each could not climb much of a grade!

If they weighed 6000tonnes and only 5000hp then you are right. That's like only having 5/6 of a hp per tonne of weight. Imagine trying to move a tonne of steel with a lawnmower engine. I'm not sure what a diesel train engine does weigh, but probably alot less than a nuclear reactor. Say they weigh 200 tonnes and 5000 hp. That means you have 25 hp per tonne of weight. Our nuclear one was 134khp/6000tonnes, or around 22hp per tonne. Now you said 4 engines @ 5000hp each... the excess power can push your cars. Plus you can afford to have 4 engines easily. To run a 6kilotonne nuclear engine would also require extremely heavy duty tracks to support the pressure. With the weight spread out, the diesel can easily be run on relatively light guage tracks. Also I think momentum plays a large role in a train's ability to climb grades. I dont think many trains can climb a steep grade from a dead stop.

Point I was making is that no matter what Al Gore says Trains will be powered by diesels for a long time.....possibly bio-diesel.

You are right. The new technology and complete overhaul of the system would cost so much that it will be a long time before they can justify a complete changeover to alternate fuels.

[AK_Gandy]

Originally Posted by NBhunter80

I'm not sure what a diesel train engine does weigh, but probably alot less than a nuclear reactor.

A locomotive can weigh anywhere from 100 tons up to 220 tons. A typical "unit train" averages about 15,000 "trailing tons" (110 cars @143 tons each).

Also I think momentum plays a large role in a train's ability to climb grades. I dont think many trains can climb a steep grade from a dead stop.

It's a function of tractive effort as determined by the "factor of adhesion" and the "ruling grade." The newer locomotives with electronic wheel slip technology has allowed locomotives to substantially increase their tractive effort and ability to start up a grade.

EMD SD90MAC Data Sheet

Tractive effort - Wikipedia, the free encyclopedia

[drcampbell]

An entire submarine displaces (has a mass of) 6,000 tons. Not the reactor, which is a small fraction of that.

A typical long-haul freight train (the entire train, not the locomotive alone) is in the neighborhood of 8,000 tons and 8,000 Horsepower. 200 tons is about right for a freight locomotive.

You're probably right that a train would be hard-pressed to climb a 10-degree grade. But they don't ever need to. Outside of the Rockies, trains seldom encounter more than a one per cent (0.6-degree) grade. Even in mountainous areas, anything more than 2 degrees (3.5%) is very unusual.

A train's ability to climb a grade is limited by wheel slip, not horsepower. Locomotives can typically achieve a tractive effort equal to 1/3 of their weight.
Horsepower does, of course, limit the speed at which they can haul a heavy load uphill. At 1 hp/ton, it's only possible to climb a 1% grade at 20 mi/hr or a 2% grade at 10 mi/hr.

Momentum only helps for the first 100 feet. After that, it's sheer muscle.

One factor which does help a long train is that the entire train often isn't on the grade at the same time. For a short hill, such as the approach & departure to/from a bridge, you first have the front half of the train on the grade and the rear half on the level. Then you have the front half going downhill while the rear half's going uphill ...

(Gandy and I must have been banging away simultaneously)

[NBhunter80]

An entire submarine displaces (has a mass of) 6,000 tons. Not the reactor, which is a small fraction of that.

A nuclear sub avoids carrying large amounts of coolant by using sea water as part of it's coolant system. A nuclear powered train would not be able to do this, and would require an extensive cooling system that would add alot of weight.

It's a function of tractive effort as determined by the "factor of adhesion" and the "ruling grade." The newer locomotives with electronic wheel slip technology has allowed locomotives to substantially increase their tractive effort and ability to start up a grade.

A train's ability to climb a grade is limited by wheel slip, not horsepower. Locomotives can typically achieve a tractive effort equal to 1/3 of their weight.

I understand that the heavier the engine, the more traction is experienced; however, I was just pointing out the amount of power required to do the work in that amount of time. Sure you could experience less wheel slip with an extremely heavy train, but you would climb very slowly.

[drcampbell]

Originally Posted by NBhunter80

A nuclear sub avoids carrying large amounts of coolant by using sea water as part of it's coolant system. A nuclear powered train would not be able to do this, and would require an extensive cooling system that would add a lot of weight.

There are better reasons for not putting nuclear reactors into locomotives: CSX-Sucks.com :: Pictures

Originally Posted by NBhunter80

... you could experience less wheel slip with an extremely heavy train, but you would climb very slowly.

Only the weight of the locomotive, not the entire train, affects how much tractive effort is available.
The weight of the entire train affects how much tractive effort is needed.

[THEBUNDO]

I thought their was a lot more friction in water. Fire a bullet into water.....