Notices
Results 1 to 8 of 8

Thread: Railroad Car Energy Storage

  1. #1 Railroad Car Energy Storage 
    New Member
    Join Date
    Aug 2012
    Posts
    3
    Wondering if anyone has any comments on the utility of a system like this:

    http://www.thesaturnwire.com/technology-from-saturn-and-neptune/railroad-car-energy-storage-system


    Reply With Quote  
     

  2.  
     

  3. #2  
    Time Lord
    Join Date
    Apr 2008
    Posts
    5,328
    Neat idea.

    Near the end you do face the fact that construction cost is enormous. Existing rails won't serve, because they're laid precisely where the grade is least.

    I think you may be underestimating the operational cost. Consider that even with this infrastructure already built, and in decline, trucks including the drivers' salaries are competitive against rail. Why not simply drive trucks up a hill?


    A pong by any other name is still a pong. -williampinn
    Reply With Quote  
     

  4. #3  
    Brassica oleracea Strange's Avatar
    Join Date
    Oct 2011
    Location
    喫茶店
    Posts
    17,036
    Surely one of the factors is how much mass you can store. You can put a lot more water into a given volume than you can railroad cars or trucks. You can probably get it down (and maybe pump it up) a lot quicker to meet power demands.
    ei incumbit probatio qui dicit, non qui negat
    Reply With Quote  
     

  5. #4  
    Time Lord
    Join Date
    Apr 2008
    Posts
    5,328
    Yeah, startup time for hydro takes no longer than releasing a gate - that's one of its great advantages. Obviously a rail car offers no quick backup to the grid.
    A pong by any other name is still a pong. -williampinn
    Reply With Quote  
     

  6. #5  
    Forum Professor Zwolver's Avatar
    Join Date
    May 2006
    Location
    Netherlands
    Posts
    1,670
    What happened to spinning a flywheel? Or spanning a spring, elastic, bending wood, etc. Why with the train carts. Haha.

    Anyone some original ideas of ways for storing energy, besides mine, that is.

    How well can static energy be stored?
    Growing up, i marveled at star-trek's science, and ignored the perfect society. Now, i try to ignore their science, and marvel at the society.

    Imagine, being able to create matter out of thin air, and not coming up with using drones for boarding hostile ships. Or using drones to defend your own ship. Heck, using drones to block energy attacks, counterattack or for surveillance. Unless, of course, they are nano-machines in your blood, which is a billion times more complex..
    Reply With Quote  
     

  7. #6  
    New Member
    Join Date
    Aug 2012
    Posts
    3
    Wow... such a lot of great feedback in such a short amount of time! Thanks everybody!



    "Existing rails won't serve, because they're laid precisely where the grade is least."

    Good point. These rails should be as steep as possible, not the other way around. However, I wonder what a financial analysis would reveal? Could be that since the existing rails are "free", then they would allow for storing energy at the lowest cost. The storage and retrieval process would be less efficient when tracks are not as steeply sloped as they could be, but the revenue lost to this effect might not be any larger than the money saved by not having to build new tracks. But... you make a good point, and I agree.




    "Why not simply drive trucks up a hill?"

    Absolutely! Excellent idea.






    "You can put a lot more water into a given volume than you can railroad cars or trucks."

    Actually, I was thinking it would be the other way around. Water weighs only 62 lbs/cubic foot, but sand weighs 100 lbs/cubic foot, and gravel weighs 150 lbs/cubic foot.



    "You can probably get it down (and maybe pump it up) a lot quicker to meet power demands."
    "Yeah, startup time for hydro takes no longer than releasing a gate - that's one of its great advantages. Obviously a rail car offers no quick backup to the grid."

    Not sure why you say this. Seems to me both systems would respond very very quickly to fluctuating demands. Water begins to flow downhill as soon as you release the gates, railcars begin rolling as soon as you release the brakes.




    "What happened to spinning a flywheel?"


    As I understand it, you can't store much energy in a spinning flywheel.



    Thanks again everybody!
    Reply With Quote  
     

  8. #7  
    Suspended
    Join Date
    Apr 2007
    Location
    Pennsylvania
    Posts
    8,795
    As I figure it you are talking about 2437 cars per hour for 8 hours, and that means you need 19,496 cars. There are a total of about 460,000 cars in all US class 1 railroads, so your system would need about 4 percent of the freight cars of all these railroads. All this for <300 megawatts.

    You will have a significant capital cost as well as maintenance costs for this much rolling stock. You might be able to use the 2.99 cents per ton-mile of freight revenue to get a ballpark idea of the operating costs.
    http://www.aar.org/PubCommon/Documen...Statistics.pdf
    Reply With Quote  
     

  9. #8  
    New Member
    Join Date
    Aug 2012
    Posts
    3
    Quote Originally Posted by Harold14370 View Post
    As I figure it you are talking about 2437 cars per hour for 8 hours, and that means you need 19,496 cars. There are a total of about 460,000 cars in all US class 1 railroads, so your system would need about 4 percent of the freight cars of all these railroads. All this for <300 megawatts.

    You will have a significant capital cost as well as maintenance costs for this much rolling stock. You might be able to use the 2.99 cents per ton-mile of freight revenue to get a ballpark idea of the operating costs.
    http://www.aar.org/PubCommon/Documen...Statistics.pdf
    Cool... thanks for the numbers. A couple of comments in reply to your post. First, I suppose a fixed (and relatively small) number of flat cars could carry heavy cylinders up the mountain, which would then be rolled off the cars at the top onto some kind of tracks for storage. Second, 30 mph is just a number I pulled out of the thin blue air to get an idea of how much area (square miles) would be required for storing heavy objects at the top and bottom of the mountain, and whether the efficiency of this system would be comparable to pumped hydro storage. I think I found out that the space required to store the weights is reasonably small, and that the efficiencies of the two systems are in the same ballpark. So far nobody has disputed these conclusions, but then again only a few people have seen it, so I guess it's possible that I am still overlooking something. But if these conclusions do turn out to be correct, I suppose the next step would be to figure out how a system like this would be optimized for energy storage rather than for moving freight. Should the train move very slowly and carry a lot of weight, or should it move quickly and not carry so much weight, or should it move quickly and still carry a lot of weight, or what? Should it have very widely spaced tracks or standard railroad tracks? What factors, if any, would most impact the viability of a system like this? I haven't even thought about any of this stuff yet. I like your 2.99 cents idea though... will have to look into that to see what it reveals.
    Reply With Quote  
     

Similar Threads

  1. Repeatable energy storage
    By (In)Sanity in forum Physics
    Replies: 17
    Last Post: February 7th, 2012, 12:01 AM
  2. Ferroelectric energy storage
    By Stanley514 in forum Electrical and Electronics
    Replies: 0
    Last Post: January 4th, 2010, 11:18 AM
  3. Solitons and energy storage
    By Stanley514 in forum Physics
    Replies: 0
    Last Post: July 22nd, 2009, 12:51 PM
  4. Future of energy storage
    By Stanley514 in forum Physics
    Replies: 8
    Last Post: May 7th, 2009, 02:56 AM
  5. Kinetic Energy Storage
    By dap in forum Physics
    Replies: 13
    Last Post: June 7th, 2007, 09:26 AM
Bookmarks
Bookmarks
Posting Permissions
  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •