The issue with inductive charging is that you need to speed up the frequency of the electricity going into the charging system in order to have components that will fit into the neccessary spaces. Speeding up frequency requires expensive solid state converters. I believe this may have been researched for light rail applications, but even there, that system does not exist outside of the lab- forget about using it to power a loaded coal train!
W
Gerry Callison, P.E. The issue with inductive charging is that you need to speed up the frequency of the electricity going into the charging system in order to have components that will fit into the neccessary spaces. Speeding up frequency requires expensive solid state converters. I believe this may have been researched for light rail applications, but even there, that system does not exist outside of the lab- forget about using it to power a loaded coal train!
Well, I think the Augsburg test is a little outside of the laboratory, but your point about balancing equipment size, equipment cost, and line losses stands.
I expect, as I've said before, that a lot of the future of auto battery power storage is going to be made by HP, Apple, Dell, Black and Decker, and so on, with R&D spinoffs from high-cost electronics providing the bulk of advances.
If I could wave a magic wand, I think I'd like to see some "fourth rail" systems, where a battery-powered slug could be added and dropped as needed, with the power passed forward through additional segmented rails. Diatto on the cheap. (But still not feasible yet, of course.)
That it is a good point about energy storage, as this could be used to "jump" sections between catenary, possibly avoiding having to raise tunnels, for example. I am very intrigued with supercapacitor technology, as it has faster charge/discharge and could probably go through a lot more cycles than a battery. Apparently there are still issues with reliability of the super capacitors themselves and the ability to "break" direct current. None the less, I say pay attention to that technology, as it could shave substantial money on the buildout of catenary.
.
Gerry Callison, P.E.That it is a good point about energy storage, as this could be used to "jump" sections between catenary, possibly avoiding having to raise tunnels, for example. I am very intrigued with supercapacitor technology, as it has faster charge/discharge and could probably go through a lot more cycles than a battery. Apparently there are still issues with reliability of the super capacitors themselves and the ability to "break" direct current. None the less, I say pay attention to that technology, as it could shave substantial money on the buildout of catenary.
I think there are already real possibilities for transit systems to use storage and regenerative braking to cut back the overall size of the electrical system required as well, if you could ignore feasibility....and, like you said, reliability. There's a lot of potential change 5 or 10 years out now.
Just Watched Mad Money this past Friday and they were interviewing some guy from EMD who said they should have a CNG or LNG unit by this fall.....what ever happed to Fuel Cells that where all the the rage about 4 years ago??
Just to throw in a odd ball...what if...there was low voltage that ran through the existing tracks that could recharge a battery tender anywhere on the system>>>Both with CNG and Eletricty you need tenders if theres no cat. But railroads have the economy of scale....Heck they were thing of nuke powered trains in the 1970s
Fuel cells suffer from a wide range of setbacks: cost due to the large amount of platinum required for the only kind suitable for transportation (in terms of size, operating temperture, and start up time); the ability to store hydrogen (it's volatile, and when you compress it to liquid, you lose 33% of the stored energy in the process); and the fact that hydrogen comes from limited resources (when you use water, you need to PUT energy into the process by separating the oxygen and hydrogen). Fuel cells were always more of a political stunt than a serious option for our energy future.
The problem with batteries is that the technology is simply not there yet. Up front costs and energy storage remain a challenge, and one must also look at the nature of the depreciation. I can buy a new electric car with a battery pack running $10-20k, but in a few years, that pack will be useless beyond a few hundred dollars scrap value. There is not cheap rebuild for a battery like there is for a combustion engine.
Ultimately, the catenary is a proven, economical technology that is ready to be built.
Gerry Callison, P.E.Fuel cells suffer from a wide range of setbacks: cost due to the large amount of platinum required for the only kind suitable for transportation (in terms of size, operating temperture, and start up time); the ability to store hydrogen (it's volatile, and when you compress it to liquid, you lose 33% of the stored energy in the process); and the fact that hydrogen comes from limited resources (when you use water, you need to PUT energy into the process by separating the oxygen and hydrogen). Fuel cells were always more of a political stunt than a serious option for our energy future.
Well, I think you have another aspect, that also partly explains the corn ethanol mess: expanding a niche outside its natural size, Politicians especially seem to have a difficulty understanding that if America needs one of something, that two or two hundred of them isn't necessarily better.
Gerry Callison, P.E.The problem with batteries is that the technology is simply not there yet. Up front costs and energy storage remain a challenge, and one must also look at the nature of the depreciation. I can buy a new electric car with a battery pack running $10-20k, but in a few years, that pack will be useless beyond a few hundred dollars scrap value. There is not cheap rebuild for a battery like there is for a combustion engine.
Something to consider, though: a car's performance is constrained a great deal by battery weight. A locomotive, not so much; the structure is deliberately kept heavier than it could be. Lead acid or edison cells are workable, and they allow a lot more value recovery as scrap than bleeding edge lithium stuff does.
Reforming inspection requirements to allow truly modular locomotion, with separable systems treated as such, would go a long way on this, but it would also make for better use of conventional diesel electric.
Inspection requirements related to modular locomotives are a fascinating issue for one reason in particular:
If we were able to exchange electricity between diesel and electric locomotives, then the system could move seamlessly between track with and without catenary. 25 kV could be stepped down on the electric locomotive's transformer and distributed to connected diesels. When the system was not underwire, the diesels could power the traction motors on the electric locomotive, thus improving adhesion and handling.
Does anyone know if something like this was ever attempted? Did the Milwaukee Road do something like that? Does anybody know what codes and rules might apply to that?
To my knowledge, the system of transferring power between locomotives that you propose has never been used for road locomotives. (Of course in discussing technology, one should never say never). The probable reason is that the motors are sized for the power source and there really wouldn't be any advantage to adding more motors. The closest siimilar application would be the use of yard "slugs" which are locomotives with traction motors, but no traction power system. They are fed from a coupled locomotive's traction power system. This system is used in yards where high tractive effort is needed at low speeds; in this case a single diesel engine can easily develop more horespower than its own motors can handle at low speed.
There are dual mode locomotives in use today, Metro North and Long Island both use Diesel/600vdc third rail types and New Jersey Transit is about to commission a series of Diesel/AC types. In these cases the reason is operation in tunnels and avoidance of fumes.
The Milwaukee Road did use diesel - electric and electric locomotives together and I think they had provision for operating both from one cab, but there was no connection of their traction systems.
Locomotive inspection regulations would most likely treat any traction unit, whether it has a prime mover or not, as a locomotive and it would require the same type of inspection.
However symbiotic, I doubt many railroad rights of way are wide enough for co-location of tracks and high-tension power lines that minimizes exposure to derailment.
It may be almost as easy to take power at points where lines and tracks cross. Furthermore, new power lines can take a more direct route less inhibited by terrain than a railroad.
Gary, Gary, Gary, what kind of Engineer are you? Certainly not electrical since you are clueless on so many levels of Electric Traction Power. Go build a road or a bridge. Everything in your note is wrong. Railroads don't want that kind of EMF induction on their property. Many have it and have huge problems. They are designing their PTC radio Train Control systems now to add to the RF and unductance and noise in their areas. I have first hand experience with all of this. You obviously have none. Adding electric traction power would also mean a 100% completely new Signal System with it. There is no dang way there is an ROI for that expense right after adding PTC. You guys are killing me. What difference does it make who is burning the fossil fuel? You need X amount of energy to move Y amount of tonnage 1 mile. Clean burn is B.S. too. Maybe you can tell me why when I buy a standby generator for a location that needs 10,000 watts, the catalog offers me gasoline, diesel or Natural Gas options. For the NG option it states, "subtract 20% for the wattage output for NG". Finally, you have no idea of the huge maintenance costs of a traction power system. One ice storm and you go dead for hundreds of miles. What do you know about line sag? LNG is a possibility but you have to check the BTUs vs Diesel. Gary, how do you plug in a moving train? You can't be serious. You don't even know that Transmission lines are not "tapped into". EVER!!!! That is why they have transmission lines and Distribution lines. I can take you to places where a voltmeter across the rails will show 600 vac. I can then ground one lead, switch to current and getfrom 1 amp to 17 amps. This is all induced current next to a power line. I have seen many places where an unbalanced distribution line was doing as you said. I will give you one check mark.
Yeah, let us invent a new wheel while we are at it.!!
You can hear firsthand about LNG for high horsepower operations -- rail especially -- at this upcoming event. HHP Summit 2012 in Houston this September will explore the use of LNG in locomotive, marine and other off-road high horsepower applications; details are at www.hhpsummit.com.
Systemsnut- if you could actually take me to a place where I could see "600 VAC" from rail to rail, and then "1-17 Amps" from rail to ground, I sure hope you would be out on your railroad fixing a train stopping, life threatening issue rather than blogging. I would respectfully suggest, however, that the first place you look for the root cause is in the systems engineer/technician, with a penchant for factually-challenged hyperbole, who is blogging about such absurd numbers. 600 VAC is a great deal of voltage, and 1-17 amps is a great deal of current. Extrapolate that rail to rail voltage into a likely rail to ground voltage, and remember that your typical US 120 VAC wall outlet is designed for a MAX of 15-20 amps, and you can see the big picture.
It also pays to bear in mind some of the fundamentals of power line EMI. Differential voltage between rails usually begins as common mode interference driven by the electric field created by a high voltage power line. The difference between the rails comes from different impedance characteristics. Also, bear in mind that this common mode high voltage interference is usually accompanied by small current levels- just like induced current from a magnetic field and conducted current interference are typically accompanied by low voltages. Power, which is the flow of energy over time, is equal to the product of voltage and current, so if you have both high voltage and high current, then you have a “unique” situation! If the impedance from rail to ground is low enough to drive real current, then the rail is electrically too close to ground to have any real voltage difference. Real as power line/rail interference can be, basic design principles present many highly effective countermeasures. Counterpoise, phase arrangement, and physical spacing of the lines on the towers are only a few of the tools available to address this issue. If you’re talking about a new, co-located power line, those principles can be worked in from the beginning.
This is just like icing on the catenary conductors. Proper power line and catenary design will take into account issues such as lightning, wind, and ice, and design structures that are strong enough and protected enough to handle it. Electrification has proven itself in such icy environments as Russia and Scandinavia. The Milwaukee Road ran electric trains across a bridge in Beverly, Washington where wind gusts were known to derail cars (though you might have some electric problems when the wind blew that hard!).
As far as tapping, that is done regularly on transmission lines up to and including 138 kV. Background for the non-power engineering public: a "tap" is where multiple power lines join without a circuit breaker to disconnect them in an emergency- basically, a 3+ terminal power line. The challenge with taps is that if something goes wrong on one leg, then all legs need to be removed, and if the legs are of different lengths, it is very difficult to set up the controls to detect faults somewhere on the tapped line in the first place. For this reason, it's not usually (I've seen otherwise in special cases) done above 138 kV. But this is an important concept with electrification because there are 25 kVAC traction systems that interface to transmission level voltage through taps in the northeastern US.
The bottom line is that studies have shown time and again that mainline electrification pays for itself. Economies of scale in generation and flexibility in fuel sources make electricity cheaper than diesel. Combine that with the higher efficiency of an all-electric locomotive drawing a fraction of the electric energy to move a train that it would need from diesel and savings from its reduced maintenance and improved performance, and all costs- catenary, signal rebuilding, locomotives- are paid for.
The challenge for electrification proponents is to find ways to further reduce the capital costs involved, and thus move it up the capital spending priority list for railroad companies. That's the beauty of power line/ rail co-location.
SIDENOTE: If anyone reading this is really interested in power line/rail interference, they should be sure to catch up with Marv Frazier, Brian Cramer, or Mike House at AREMA in Chicago in September- these guys make a living off of power line/rail interference and know a great deal more about it than I do.
OK, I can accept that an electric locomotive can have lower operating costs than a diesel, mostly because electricity is generated from cheaper fuels, but you're going to have to explain to me why an electric locomotive draws a fraction of the energy of a diesel. They weigh about the same, they use the same power conversion technology; the diesel has limited power transmission line losses; the diesel doesn't require several tranformers in the path between its prime mover and traction motors. The diesel engine itself has about the same thermal efficiency as a central station prime mover. On the other hand, the diesel may use more energy in getting its fuel from the well to the engine, but that is a characteristic of geography.
Bottom line is, you have to look at the situation from well or mine to wheel, and it isn't that much different.
Fair question, John. To understand why an electric locomotive draws a fraction of the energy of a diesel, we should look at the energy process from either side of where the railroad purchases the energy.
From the ground to the railroad, both diesel and electrification involve some similar processes. Oil is mined/drilled, shipped to a refinery, then refined into diesel, which is transported to a locomotive fueling station once the railroad buys it. Electricity begins life likely as coal, natural gas, or uranium, which must also be mined/drilled (unless it’s renewable or falling water), is transported to a power plant, then converted to electricity, which is transmitted to a railroad’s substation, where it is purchased.
Things start to get a little bit different after the railroad purchases the energy. The diesel must go through a combustion engine, which is in the neighborhood of 50% efficient, and then goes to an electric drive system which powers the train. The electricity, however, goes through a transformer, whose efficiency is in the 95%+ range, before it goes to the electric drive system. There is also no idling in the all-electric train, which draws only the amount of power that it needs at any particular moment (assuming no advances in super capacitors, which may be coming, and would make the locomotive a lot lighter on the electrical grid).
So essentially, the railroad saves a ton of money by not having to buy extra diesel to create a bunch of waste heat in its locomotives. This is in addition to the fact that electricity is cheaper to begin with, due to a diversity of fuel sources (most of which require less refining than diesel) and economies of scale.