Yard service is a perfect application for these types of locomotives. Diesel fired locomotives tend to sit around idling and burning fuel many more hours than they are being used every day. Diesel locos also tend to not be very fuel efficient when constantly stopping/starting around the yard.
These new locomotives are from Progress Rail, division of Caterpillar, and from Wabtec, which is Westinghouse Air Brake Technologies, 150 years old. They're just Diesel-electric platforms with batteries replacing the Diesel.
"Replacing" may be just that. Few locomotives are built for yard work today. Most US switchers are old road locomotives, often half a century old. Sometimes they have a new power package. Progress Rail started as a locomotive rebuilder, changing out power packages for new ones, usually Caterpillar Diesels. Their electric seems to be a repower job of a classic General Motors Electro-Motive Division GT. Here's a video of their standard new Diesel repower job.[1]
Lithium iron phosphate batteries, at least in the Progress Rail version. The heavier weight of lithium iron phosphate is a feature, not a bug, in a locomotive. Locomotives are built heavy to improve traction.
The end result is not just a yard locomotive. Some of these are in test elsewhere for short-haul lines. Range maybe 300 miles.
Another boring, but useful, technology, from old-line industrial companies. This is what makes the world go.
> Few locomotives are built for yard work today. Most US switchers are old road locomotives, often half a century old.
Here in Germany, we still build new models of railway shunting engines such as the Voith Gravita [1], and we have nearly a thousand (!) of the old V60 in service [2]. Normal open-track models may have superior fuel efficiency at higher speeds, but commonly lack the from-zero traction capability of a specialized shunting engine.
> Is the "electric" part of the diesel electric a commoditized technology?
Not really. You can't use the electric side of a locomotive drive train anywhere else than in a locomotive, and for fully electric locomotives you can't even use the transformers in any non-railway setting simply because the frequencies used are generally incompatible with usage on the normal power grid. Old electric locos sometimes are used to provide auxiliary power for parked cars [1], though that has fallen out of fashion here.
What is commoditized is the engine side of a diesel locomotive, that's your run-off-the-mill CAT, MTU or whatever industrial diesel engine. As long as it fits into the locomotive body and accepts a hydraulic or electric generator at the output, it can be used. IIRC there even were some experiments with gas turbines on French high-speed locomotives, but these had atrocious fuel economy.
> Is it a single motor or one per axis?
That entirely depends on the engine model, and can be inferred from the wheel arrangement code [2].
The usual setup on newer locomotives is that all the wheels are powered by 3-phase motors. Semiconductors the size of bricks control the power, with an AC to DC to variable frequency AC conversion setup. All the wheels are forced into sync by the control system. Multiple locomotives coupled together synch up their wheels.
The motors are down near the wheels on such locomotives. No transmissions, differentials, or clutches.
This locked-together wheel drive is a huge win. No more wheel slipping and spinning. Wheel slip has been a huge headache with locomotives back to the steam engine era. The effect is to almost double drawbar pull. Starting heavy trains on upgrades now works much better.[1]
There are many other classic ways to build locomotive drivetrains, but this won out.
UP 4014 "Big Boy", biggest working steam locomotive: 135,375 pounds tractive effort.
General Electric ES44AC, common road locomotive today, over 3700 units built: 183,000 pounds tractive effort.
Dull, boring, from old companies, and very effective.
> You can't use the electric side of a locomotive drive train anywhere else than in a locomotive, and for fully electric locomotives you can't even use the transformers in any non-railway setting simply because the frequencies used are generally incompatible with usage on the normal power grid.
This is a surprise, because it calls to mind this old story:
A locomotive can still output a transformable voltage if you disconnect the traction motors and instead hook them up to something else. A Diesel-Electric engine really is just a generator riding on top of an electric locomotive.
In this case they took MLW M420W locomotives and just straight hooked them right up to the local grid.
That doesn't sound far off from a PTO generator, assuming you've got the right interconnects exposed seems reasonable. From my limited understanding most diesel electrics go Diesel -> AC -> DC -> AC -> Wheels. If your taking power from the first AC part the engine RPM determines frequency(as with a PTO generator). Most diesels used in these applications with similarly buffered powertrains(some tractors/heavy machinery with HSTs/etc) have good governors to keep the engine from running away.
From the article it sounded like it wasn't ideal(there was damage to the gearbox from driving the engines down the road).
(as an aside this is why I think a diesel-electric tractor or pure electric would be pretty nifty thing)
> (as an aside this is why I think a diesel-electric tractor or pure electric would be pretty nifty thing)
Electric motors on tractors are an absolute rarity (usually, the motors need cooling, which is in conflict with the wheel/tracks being rated for driving through water and mud).
The usual is either direct drive or using the hydraulic generator for the power tools and actuators also for the drive train... and you can get electricity generator packs that you can simply plug in into the hydraulics port for a power tool [1].
> What is commoditized is the engine side of a diesel locomotive, that's your run-of-the-mill CAT, MTU or whatever industrial diesel engine. As long as it fits into the locomotive body and accepts a hydraulic or electric generator at the output, it can be used. IIRC there even were some experiments with gas turbines on French high-speed locomotives, but these had atrocious fuel economy.
The diesel prime mover is usually an EMD or Wabtec/GE engine in the US - very few mainline locomotives use anything else. They are medium-speed engines and two-stroke (EMD) or four stroke (Wabtec/GE with some EMD Tier-4), built to be reliable, cheap and nearly indestructible. You can swap other engine makes in, but usually with worse reliability and performance.
Outside the US other engine makers are more prevalent, but interestingly US engine designs are the most numerous (except in former Soviet states and China). In the US, newer non-road engines may use Tier-4 MTU or CAT engines for eco friendly power, but they're still the exception and not the rule.
A relatively-new player in the US is Siemens. They're building new passenger locomotives, including electrics for the Northeast Corridor and diesels for elsewhere. The SC-44 Charger and its derivatives [0] use Cummins QSK prime movers, which are high-speed diesels comparable to Euro designs.
A bit off topic, but I find it mildly amusing that most of the article is taken by the huge table that is entirely about steam loco wheel arrangements, and moreover all of those various arrangements actually have their own article! Rather thorough for a decidedly obsolete technology.
While you can't use the motors 1:1 from what I understand a lot of the development of VFD AC motors happened in the locomotive space[1].
The traction of a DC drive vs AC drive is significantly different(the below article cites at least 2x better for AC) in part due to the fact that a DC motor will "run away" once it breaks the static friction limit where a VFD(holding a fixed frequency) will self-correct as the wheel overspeeds and is slowed down by the other side of the magnetic field. Since most EVs use AC VFD a lot of that same development can be applied in traction applications.
One motor per axle except in the Wabtec/GE ES44C4 and ET44C4 where it is four powered axles and two idle axles (Progress Rail has a similar locomotive that didn't make many sales)
For context, Progress Rail is what became of Electro-Motive Division when GM split them off, and Wabtec bought the locomotive division of GE a few years ago.
AFAIK, most "diesel locos" are really diesel electric, with the diesel engine feeding a generator. Hybridization of locomotives seems like a no brainer since they can recover so much more energy with regenerative braking and can plan for braking to be recovery efficient.
As I understand, braking occurs across the entire train, not just via the drive axles, so the hybrid regeneration method would be a considerable departure from normal operations.
Yes, but diesel-electric locomotives have a brake mode where the "regenerative" current is shunted through big air-cooled resistors and exhausted as heat. Often used on downgrades to control speed without burning up the brake shoes. Recovering this into battery charge would be an easy win, though you might still need the resistors after the batteries are fully charged or if they can't absorb the charge fast enough.
This is where overhead electric is great, and why the Pennsylvania railroad ran full electric over the mountains back in the steam era. A coal train going down the mountain could mostly power the one going up.
I have the impression that engaging the airbrakes is a little bit all-or-nothing.
They're great for stopping (relatively) quickly on level ground. But not so grest for controlling your speed.
Big diesel-electric locomotives have large, actively cooled resistor banks, usually on top of the engine. When rolling down hill they run the electric motors as generators, and dumping the energy into the resistor banks.
The mechanical brakes can't absorb that much energy - they'd wear out after a few minutes.
The end result is waste heat. Capturing it would be great, but a battery is needed for that. Capacitors are still not up to the task for that amount of energy.
Yep, battery energy density is still far off from fossil fuels.
This is from 2012 but still relevant and why we don’t have electric commercial passenger planes, and probably never will until we make 10x gains in energy density:
“””
Stored energy in fuel is considerable: gasoline is the champion at 47.5 MJ/kg and 34.6 MJ/liter; the gasoline in a fully fueled car has the same energy content as a thousand sticks of dynamite. A lithium-ion battery pack has about 0.3 MJ/kg and about 0.4 MJ/liter (Chevy VOLT). Gasoline thus has about 100 times the energy density of a lithium-ion battery. This difference in energy density is partially mitigated by the very high efficiency of an electric motor in converting energy stored in the battery to making the car move: it is typically 60-80 percent efficient. The efficiency of an internal combustion engine in converting the energy stored in gasoline to making the car move is typically 15 percent (EPA 2012). With the ratio about 5, a battery with an energy storage density 1/5 of that of gasoline would have the same range as a gasoline-powered car. We are not even close to this at present.
“””
Part of the issue is not just the density of the fuel but also the fact that the weight remains the same no matter how much of it you use. With gasoline/coal/etc. when you use the product it then decreases the weight of the amount of fuel stored, you don't get that loss with batteries so while you get "additional" gains with e.g. aviation fuel the further you are along your trip and the more you've burned, you don't get that with batteries.
While I agree about aviation, rail is an entirely different problem, and big heavy things move great.
For freight in the US, the worst case segment I know about is ~700 miles. This can be handled with about 400-500 feet of battery cars, which is probably 5%-10% of train length. So the worst possible scenario is pretty close to feasibility with current tech.
If railroads were to start investing in this level of battery, beyond saving a lot of fuel costs, they'd have a couple hundred MWh of battery at every rail station. This would be a significant grid asset, at least at the moment. In a decade, that level of storage is probably going to be extremely common. But in any case, there's significant opportunity for demand response payments, if not using the batteries for replacing peaking power on the grid.
Rail is 2% of transportation emissions, which is 29% of total US emissions [1], which was 6.558e6 metric tons in 2019 [2]. So rail is 3.8e7 kg of CO2 emissions. Diesel emits 10 kg/gallon [3], so that's 3.8e6 gallons, and at a cost of $3/gallon that's only $10M dollars out of what is an $80B industry [4]. That's so vanishingly small that I wonder if I have done something wrong here...
Eviation is about to start testing a prototype small electric commercial passenger airplane. It will only be suitable for short flights with a few passengers, and it's not clear whether the economics will work out.
For larger airliners there could eventually be a role for plug-in hybrid propulsion systems. Use a fairly small battery pack and electric motors to augment the turbines during take-off and climb, then switch them off during cruise. There would be a weight penalty but it might deliver a net fuel savings for shorter flights.
They won't. If you ever flew in these small aircraft, you know that they are extremely susceptible to weather conditions, and can be easily grounded due to rain, snow, strong winds or extremely hot weather.
Even ignoring the heavy batteries giving them range that's barely acceptable, you'd still need to pay pilot's salaries per every few passenger, a major cost even when divided between the far larger amount of people flying on an airliner.
Put overhead lines on even sections of long range rail lines and you could use it for long haul. Battery could be used to bridge between sections with power.
Then generate power at a coal or natural gas power plant. Until we get further along with renewables, the total environmental impact of replacing everything with electric today probably isn’t worth it.
I remember having a heated discussion with someone about this at work, and it came down to where you were charging that Tesla and if you had rooftop solar (not even discussing the environmental impact of mfg + shipping + installation + support + useable lifetime of the solar panels, home batteries, and support accessories).
And at the end of the day, moving around a 5000# Tesla or 6500# F150 Lightning takes a lot more power in any form than a 3400# Civic / Camry.
My understanding is that bulk power generation is probably more efficient than having the motive power in the locomotive itself.
There are also isolated use cases that the US railroads have been electrified for in the past (a lot of it was de-electrified to artificially boost revenues with asset sales in the midcentury). Namely
* mountain tunnels; a fair amount of Western mountain tunnels can only accommodate one diesel train at a time due to ventilation, and the crews carry respirators and oxygen in case the train stalls inside
* any sort of long sustained slope; downhill trains using regenerative braking can return electricity for those going uphill
Trains are very efficient at carrying weight, especially if they can dump power into the grid (or battery) when braking. That metal-on-metal wheel has super low rolling resistance.
Sure. But you also need a whole lot of them to provide sustained power to move a large train for a decent trip length.
> especially if they can dump power into the grid (or battery) when braking
Smaller benefit here to regen. Sure, a 10000 tonne train has a lot of kinetic energy-- maybe 3 gigajoules or something. But compare to > 50MW to keep that train moving at a decent clip. So a complete stop with 100% of the energy recaptured is only about 60 seconds of rolling resistance energy use.
I think the cost of batteries is going to be a bigger issue than the weight. Which is why hybrid (battery combined with overhead power lines) looks so attractive to me.
> Which is why hybrid (battery combined with overhead power lines) looks so attractive to me.
It may be good for some segments, but consider the number of charge cycles and charge/discharge rate, along with the peak charging currents on the overhead lines.
For, say, 10000 tonne trains, 15MW sustained is a good very optimistic target for how much power you need to put out to keep rolling (before you make this any worse with adding battery mass and before you consider e.g. slopes, braking, etc).
If your goal is a discharge rate of C/1, you're carrying 75 tonnes of batteries-so it masses about 1% more.
Then, what duty cycle are you charging at? 100% coverage from the overhead power lines means you need to bring 15MW into the train. If the goal is a big saving in the amount of overhead power lines needed, 10% coverage from the overhead power lines means you'll instead need to bring 150MW into the train during those spans (and, this is a really aggressive 10C charge rate...)
I think C/1 is too aggressive for good cycle service, 10C is waaaay too aggressive for charging-- and these are best case scenario (flat ground, etc). If you multiply the amount of batteries by a big amount, now the mass change to the train and the rolling resistance contribution to the train from batteries becomes significant).
edit: in the end, I think you're usually better off just electrifying the portions of the train route where it's easiest, and burning diesel the rest of the way, instead of trying to somehow dotted-line-overhead-electrify things and limp through with batteries.
Agree that 10% coverage is too low, but for 50% coverage charging speed falls to 1C, which is totally doable (and as you say, for diesel-electric hybrid it could start making sense at even lower percentages).
The Pareto principle means that even if battery capacity means you need 80% or 95% coverage you could still see large savings over a 100% electrification.
Remember that you can also coast. If it's just about a low bridge or short tunnel you might lower the pantograph a few 100 metres on either side of the bridge. No need to wear the battery at all for such a short stretch - even with the brakes fully applied the train takes about a mile to stop. Trains don't currently do this because they don't have sophisticated position-based pantograph control and if they had to do an emergency stop under the bridge they would be stuck, but with more advanced control computers and battery backup both those problems can be solved.
Where I live they are electrifying 150 miles of track. This means 85 bridges need to be raised, demolished or rebuilt, and it's a big part of the cost. And Denmark is pretty flat - there are no tunnels as far as I remember.
By the way, 50MW seems way high to keep the train moving. The locomotives are 3-4MW peak and I rarely see them use more than 3 or 4 of them on a train. And I would expect them to be using much less than peak when they are not accelerating or hauling up a steep grade. https://en.wikipedia.org/wiki/GE_Dash_9_Series
50MW is too high (I overestimated freight train speed); I revised to 15MW on my previous post (too low).
> The locomotives are 3-4MW peak and I rarely see them use more than 3 or 4 of them on a train.
3-4 locomotives is typical for a "small" 3000 tonne train.
When you get to the 10,000 tonne monsters, you might have 8 GE Evolutions distributed, capable of 24MW sustained.
It's also worth noting this is not really enough. If rail freight was a little faster, it could be used for more things.
> 50%, which is totally doable
The US rail freight market and scale is different from Denmark. I don't think you understand how much goods travels over track which is near nothing and very long. Especially in the Western US. E.g. Los Angeles to San Antonio is just one of many major rail route. It's through 1200 miles of largely desert with nothing around. Estimates are that it would cost $5M/track mile to electrify.
Just to note the scale difference: Banedanmark moves about 2.6 billon tonnes-km according to Wikipedia. BNSF and Union Pacific railroads-- the #1 and #2 rail freight carrier in the US-- move about 1500 billion tonnes-km.
On the other hand, it takes about 12L of diesel to pull a tonne of freight across the distance.
We'd be far better off trying to just move more freight to the existing rail network than to try and electrify it, if we're looking at things from a standpoint of reducing CO2 emissions.
Sorry-- When I quote from earlier ones I lose the window and I sometimes screw up quoting.
ON THE OTHER HAND, you seemed to imply 95% electrification was plausible... so I don't think I got the spirit of your comment wrong. If 50% isn't even plausible, then it's all a bit moot, isn't it?
[Also, note that if you have 50% coverage and are charging at 1C, you're also putting 1 cycle on the battery per 2 hours].
I think you're generalizing from a small market, with much less rail in empty space, to a massive market, with lots of rail in empty space, that moves a very large chunk of goods by rail.
In addition to the other comments, buyers aren't generally deciding between a 1/2 ton pickup and mid-size sedan anyway, or a luxury car and a small compact sedan.
And I agree it really varies where you live and other variables, but that to me doesn't matter when
1) ICE vehicles aren't really that efficient anyway.
2) Even ignoring the first point, it's possible electric vehicle owners are more likely to get much of their electricity from greener sources than non-electric vehicle owners, and the extra demand on the grid requires more energy production to be built, and new energy production is probably going to be a lot greener than old sources.
3) A lot of people are somewhat environmentally conscious but only as convenience and their current lifestyle allow. People know a Civic is probably more environmentally friendly than 99% of cars, and don't care.
Then you can get in how many oil spills have been prevented, etc.,
Even the most perfect internal combustion engine only manages to turn 20% of burned energy into motion. You can understand this intuitively by realizing every gas car has a big radiator whose sole job is to dump energy into the atmosphere quickly.
Two-stroke Diesel engines used in ships have an efficiency well over 50%, up to 59% for those with waste heat recovery systems.
High-temperature gas turbines can also have efficiencies over 50%.
Modern four-stroke internal combustion engines used in cars and trucks can have an efficiency over 40%, up to 45%.
That said, such efficiencies remain low compared to electric motors with efficiencies over 95% and with combined cycle power plants which can reach an efficiency of 65% (while power plants with heat cogeneration may reach efficiencies around 80%).
The efficiency of a modern engine at best is what you say. However in the real world you rarely see the best and so the other claim is also right, your typical car is running around 20%efficient ,but it can get over 40
Sure, hooked up to a bench with ideal temperature, RPM, throttle, auspicious planetary positions etc. Put that same engine in a car that drives around and you won’t see anywhere near that.
> I remember having a heated discussion with someone about this at work, and it came down to where you were charging that Tesla
This sounds like a faulty analysis.
Generally even if 100% of your electricity is something moderately bad, like natural gas, end-to-end power use is better than an ICE with gasoline.
Figure an electric car is 150 watt-hours per mile, and charging is 94% efficient (pessimistic, but makes the numbers round). Natural gas is 0.4 kilograms/(KWhr), so about 65 grams of CO2 emitted for that mile. Compare to 8.5 kilograms of CO2 emitted from burning a gallon of gas, so you'd need to get 130 miles to the gallon to be equivalent.
Considering lifecycle costs makes things closer, but not super close.
> and if you had rooftop solar
Most people charge at night, so your own rooftop doesn't help. (Also, most places the renewable mix is worse at night, but not in all: in some places wind and hydroelectric "win").
> And at the end of the day, moving around a 5000# Tesla or 6500# F150 Lightning takes a lot more power in any form than a 3400# Civic / Camry.
More mass means slightly more tire friction and means more kinetic energy-- a big fraction of which you get back in regen.
The equation is so complicated. The petrol burning car has to get fuel. You have to drive to a station that had to be built, the station has to be staffed and the fuel and staff hauled there.
Obviously electric requires infrastructure too, but it would be good to see a full breakdown and I can’t find one.
It's an initial step. I'm not sure if the technology would work for their main routes, but this at least is a step to test and evaluate how this technology works.
Main routes are better served by combusting manufactured carbon neutral fuels airlines (United recently flew a route with 1 engine burning this fuel) are testing, using hybrid locomotives with smaller batteries for kinetic buffers. A big Chevy Volt essentially.
Electrifying US rail outside of switchyards won’t ever be practical, unless you could drive down the cost of electrified tracks with a third rail (overhead electric at this scale would be obscenely expensive).
> Electrifying US rail outside of switchyards won’t ever be practical
Why is that? Russia, a considerably poorer country beset by endemic corruption and other major issues, has managed to electrify the 9000+ km (considerably longer than any coast to coast US railway route) Trans-Siberian railway. With overhead lines, obviously.
Political and engineering will first, with cost a secondary concern (but still wielded as a reason not to). It makes sense, with enough clean energy, based on the cost of emissions offset by freight rail electrification to expend the capital required. Perhaps issue green government backed bonds to pay for it or print some more money. But we can’t build large infra projects in the US anymore, for a combination of reasons: nuclear power plants, California high speed rail, etc. [1] [2] [3]
Personally, I would prefer electrified freight rail, I’m just unsure if the US knows how or can do it. I suggested third rail if the cost came down because in America, you can usually coax towards the right solution if you can show drastic cost savings/reductions (see the rapid renewables uptake as costs declined over the last decade). At a glance, it seems easier to throw down a third rail while doing track work versus the construction effort for thousands of miles of overhead gantries and 25kv power lines. You could pair this with HVDC transmission lines looking to use railroad right of ways to avoid NIMBYS (the SOO HVDC line in the Midwest, for example [4]), for power accessibility.
I'm not sure that CAHSR is an example of why we can't build infrastructure. They're building it. There are YouTubers that have done drone flyovers of most of the first construction packages, and progress is being made pretty quickly. I have a feeling that too much has been done to cancel the project now. The corresponding Bay Area projects seem to be proceeding as well (CalMod, CalTrain electrification, etc).
Texas Central also seems to be making progress on Dallas-Houston high speed rail.
That said, I agree that the taxpayers don't feel like giving billions of dollars to BNSF and Union Pacific, so they probably won't electrify until there is no other option. Fuel costs just aren't high enough to make it profitable, and the environmental externalities are still free. (But, of course, you'd rather see a 500 car freight train burning fossil fuels than 500 tractor trailers driving down the interstate burning fossil fuels.)
It's pretty troubled project. Way over budget and when it opens in 2025 you will be able to go only as far as Bakersfield. The last section to LA is still in "environmental review" (ie fighting the Nimbies).
Yeah, that's a good assessment. It is troubled, but I don't think you can do big projects without trouble. Think about how high tensions can get when planning a two week software engineering sprint. Now imagine a project that's a million times bigger than that, where people will have their houses torn down. There's going to be some trouble. What is amazing that despite the trouble, some progress is being made.
(There are lots of things working against CAHSR. The route has been chosen politically rather than to minimize SFO-LAX travel times. Given infinite budget, you travelers on that route don't want to go through Bakersfield, as it's out of the way. And, the SFO/LAX city pair is already not a particularly optimal pair, it is kind of reaching the high end of distances that make high-speed rail the best travel option. That's why I look at Texas Central and Brightline for models of what to do in the future. Texas Central is a really good city pairing, in a region where their 16 lane highways can't handle the traffic volume. But I temper my enthusiasm in that not a lot of construction work has been done; I can't find any updates newer than September 2021 when the CEO said pessimistically that there is only a 50/50 chance that construction will start in the next 6 months. We're near the end of those 6 months.)
I just saw a blurb that they've just finished pouring the last foundation for the overhead catenary system.
Currently half of the work going on right now is grade separation that includes both the future high speed rail line and the current freight rail line. So there is some method to their madness. The grade separation provides immediate benefits.
The US government used to be able to create top notch infrastructure but something seemed to just break in the 1970s/80s.
Unless things get so catastrophically bad (see Katrina) it is impossible to convince anyone to spend money.
The government is spending money on infrastructure, it's just not very good infrastructure. You can open up any state's department of transportation website and find billions of dollars worth of ongoing projects for widening roads. These are not the projects people dream about, but they do satisfy the people that are invested in the suburbs. A lot of advocacy revolves around "live in a dense urban core, work in a dense urban core, and travel to other dense urban cores", and people just aren't doing that, so it does make some sense that politicians with 2 year terms aren't champing at the bit to do those projects instead of "widen congested freeway" (even though we know that never solves the problem).
> it is impossible to convince anyone to spend money.
They don't need to be convinced to spend money. They are spending more than ever. But you're dead on about it all being crisis-driven now. Or maybe it always was? WWII was clearly that, then the cold war/space race, then Star Wars, then GWAT (or GWOT?) -- Global War Against/On Terrorism, and now Covid - Build Back Better. Crisis spending is perfect cover for pork and grift, because anyone who questions it can be painted as unpatriotic.
I wonder if they have done studies on what the cost of electrification is for hybrid trains. A lot of the complication of electrification is that you have to raise road bridges to make space for the overhead power lines, you have to make tunnels larger and you have to put power lines 100s of places where they are really hard to install.
But imagine a train that can go for a kilometre or two without power lines, because it's a hybrid. Suddenly every low bridge and most tunnels are handled by just lowering the pantograph (power pick-up) as you go under them. If lines cross in strange ways or go under buildings you just don't put power lines there. At level crossings you skip the power lines, so no tall trucks will hit them.
I think there are probably huge savings to be made by putting the power lines in the easiest places and bridging the rest with hybrid. The battery recharges at speed as soon as power returns. You can even install a small diesel motor on the locomotive that has enough power (with gearing?) to creep to the next overhead power line if the train is unexpectedly stranded.
When a power line is downed by a tree (or a cable thief), the cleanup crew just removes that section. It is put up later when the backlog from the storm has been cleared.
Of course you need the train to know its location and have an updated list of where to lower the pantograph. That seems to me like a totally solvable problem in 2022. It's like 100 times easier than a self-driving car or landing a rocket with retropropulsion.
In the UK we are actively planning in battery electric hybrid trains. The idea is that you can easily retrofit 90-95% of the line with overhead power, and use relatively small and cheap battery systems to cover the other 5%.
You say it is necessary to lower the pantograph before (and re-raise it after) a gap in the line. Isn't it possible to (say) have the line smoothly rise before the gap - sort of lift away - high enough to disengage from the pantograph before the gap - so that the pantograph can be kept in the same position ? I'd think this would save on wear & tear and avoid accidents. How much upward pressure is applied by a pantograph anyways ?
A lot of the gaps will be there because there is not enough head room for the wires. In that case whatever caused the missing head room would rip off the pantograph. Since you need the pantograph-lowering feature anyway you might as well use it everywhere and avoid having to build the smooth-rising smooth-lowering cables.
Third rails are even more expensive for freight railroads.
* Double stack well cars sit very low. There are currently no third rail installations in the US that wouldn't get sideswiped by a well car. So their installation would basically mean forgoing half of freight revenue.
* Third rails have to operate at lower voltages due to the fairly small clearance to the ground, and so they require more frequent substations than higher voltage overhead wires.
Have any resources you’d recommend for learning more about the logistics of third rail power systems? Would you happen to know what the clearance is for double stack well cars?
Edit: excellent resources, thanks all for replying.
Third rail systems typically work at 1500V, can't go very much higher than that due to risk from arcing. Most overhead lines use 25kV, allowing much more power to be transferred, over longer distances.
Which is why third rail systems are usually only seen in metro lines and similar. I'd guess in urban environments sprinkling more substations around isn't such a huge issue, as access to the power grid is seldom an issue. Also metro trains need much less power than a high speed passenger train or a heavy freight train.
with metros the additional consideration is tunneling.
generally speaking, third rail allows for a smaller tunnel diameter than overhead systems. (third rail is located near the wider section of tunnel in the middle whereas overhead requires extending the height.)
There are overhead rails you can use in tunnels. Nothing stops the high voltage arc issue (the whole advantage of overhead is high voltage), but without all the equipment to tension the cables you don't need as much room and the power will be one the middle of the tunnel.
Anyone building new tunnel should allow the little extra room for overhead, but retrofitting may not be worth it.
Grade crossings are fine for passenger multiple units (have pickup shoes at both ends of the train and a gap either side of the crossing) but not great for locomotives.
The other big problem (in addition to the ones you've outlined) is that having miles of live conductor at ground level isn't particularly safe - for track crew, trespassers, or wildlife.
Britain has essentially stopped installing third rail for all these reasons. It's all 25kV overhead now.
> Grade crossings are fine for passenger multiple units (have pickup shoes at both ends of the train and a gap either side of the crossing) but not great for locomotives.
And the same issue also applies to every instance of pointwork.
> Electrifying US rail outside of switchyards won’t ever be practical, unless you could drive down the cost of electrified tracks with a third rail (overhead electric at this scale would be obscenely expensive).
India has electrified almost 50,000 kilometers of track with overhead wires and this is increasing eabout 5000 km a year.
China has almost 100,000 km of electrified rail track.
So very likely whatever barriers to electrification there are in the US are largely self inflicted and maybe corruption or regulatory capture driven.
Here's a Wabtec video [0] about their battery-electric locomotive. They are not limited to yard service; they're also marketing them as "hybrid consist" pullers, which means that if you team them with a standard diesel-electric locomotive they reduce the diesel fuel needed to pull the train and they capture some of the train's braking energy to recharge the batteries.
Left unstated is whether the diesel-electric locomotive in the consist could recharge the batteries of the battery-electric locomotive as the train is rolling. I expect it could but it's probably pointless because it's more efficient to let the diesel-electric pull the train.
Well, if you could store electricity from the diesel to the batteries on a level run, then you could use the stored electricity to help the diesel up a hill.
Since current locomotives are diesel electric hybrids anyway, seems like US Railroads could electrify certain potions of track, maybe steep changes in grade or places where trains frequently stop/start, yielding an opportunity to cut diesel consumption 50% or more on certain routes, since maintaining speed requires modest effort.
Also, while reduced fuel consumption is nice, another major beneficiary would be the environment, specifically when operating in urban centers. I’ve lived near heavy-use railways and currently a switching yard for most of my life, and some days the diesel exhaust is quite strong, depending on the prevailing winds. The engines are usually pretty clean burning for the amount of work they produce, but not always…
"another major beneficiary would be the environment, specifically when operating in urban centers"
But you see, they don't care. If there is no incentive for them to do it, why would they? Good neighborhood-will will pay for a donation to a local charity cause, etc, but will not make meaningful expensive changes to the SOP.
Ideally this is the point where a regulator (of some kind) steps in and nudges the change. We all know what the political problems behind that are - despite mounting evidence of how damaging diesel exhaust particles are to us, and our children.
You are correct, i started to make the point that the environmental argument is probably the best way for legislation to coerce Railroads to modernize where it makes sense. Rather than paint the Railroads as baddies, makes more sense to approach the narrative collaboratively, that technology and some thoughtful complexity could help them save a lot of money and save our lungs along the way.
An un-mentioned advantage for battery-electric locomotives, especially for yard duty - trains are already composed of many heavy modules (locomotives and freight cars) which are pretty quick & easy to switch in & out. If (at least to start) you put the batteries in old gondola cars (roughly, a flat car with low sides, designed to carry heavy scrap metal & such), then it'd be easy to have a few "battery cars" charging on a special siding somewhere, while the locomotive and currently-in-use battery car are working.
Side note on supplying power to battery-electric locomotives from overhead wires (via pantographs): The railroad industry has a lot of experience with pantographs, overhead wires, and the infrastructures needed to power said overhead wires. That stuff is expensive to build and maintain. And if your RR depends on it, then you can be utterly screwed when a large blackout occurs. Or (say) when all the power lines in an area have to be turned off, because the wildfire danger level is too high.
I've seen (non-passenger) railroad yards in Switzerland, and they seem to get along fine with overhead wires. But the infrastructure there is much better in the USA, I get why we can't do it here (nor in Canada or in Australia for many routes).
So ridiculous. Is private rail so dysfunctional that it actually makes sense to buy battery-electric locomotives in the US instead of installing overhead wires?
It would cost hundreds of billions of dollars to string up the overhead wire by themselves, and that's using the lowest cost electrification jobs done world-wide. It would cost hundreds of billions more to actually clear bridges and tunnels for the extra height needed for catenary. Then you'd have to actually buy all of the locomotives (not even going to speculate there). And then there's probably significant extra cost in building out transmission infrastructure to the railroad tracks--I'd guess there's large slices of the West where there's nothing around nearby you could hook traction substations up to. All-in-all, you're talking about a trillion-dollar investment to do so.
At the same time... the performance benefits really aren't worth it for freight trains. Remember that diesel locomotives are already an electric drivetrain--the diesel is merely fueling a generator that's sitting on board to power the drivetrain. The big savings with electrification come with weight reduction--and with freight, the weight of the locomotive is a small component of that weight--or using EMUs that let you have every wheel being powered (and with freight cars, that's again never going to happen).
According to this study from 2012, the cost of electrifying railroads in California is about $4.8M/track mile, and according to google, there are about 140,000 route miles of freight rail in the US.
I'd assume that doing this in bulk might drop the costs substantially, but we're still talking about a huge network.
It's not necessarily doing it in bulk that would make it cheap, it's basically turning it into an assembly line capable of doing a small amount of miles every year for ever cheaper cost.
American infrastructure projects tend to be super big, then don't do anything for 10+ years before you kickstart everything up again. This is a fairly poor idea if you want to keep knowledge around from the last time it was done.
It's one of those things that's kind of useless if you only do a small number of miles a year though - if you don't have the ability to make the entire journey electric, you have to involve two locomotives and the cost to switch them. That might be why Battery-Electric looks good, as you only need to electrify the two stations.
My understanding of how these work is that when not connected to wires directly, a diesel generator supplies electricity instead. So partial wiring is possible with these. Amtrak has some additional constraints (they can't run diesels under the Hudson River) but to some extent a lot of freight operators have similar restrictions but deal with them differently; due to ventilation concerns, most Western mountain tunnels only permit one train in them at any given time, and the crews have to carry respirators and oxygen in case the trains stall inside the tunnel.
It's not too hard to make locomotives that can use electric power in addition to diesel, because the architecture is already an electrical connection between the diesel generator and the wheels.
This is for yard traffic. It makes sense to me. Which part doesn't make sense to you? For ports where they are double-stacking containers onto well cars, overhead wiring would be challenging, and you still need all-new locomotives.
> For ports where they are double-stacking containers onto well cars, overhead wiring would be challenging, and you still need all-new locomotives.
That's not really a big challenge; this is something done globally on a daily basis. Typically you either have an entirely unelectrified siding and shunt in/out of it, or you have only the near end of the siding electrified and propel the cars into the siding.
Yes. Overhead wires make the value of the rail go up and so the taxes the railroads pay is more and thus it isn't worth it.
For the busy routes it would still be worth it, but the is a lot of used just often enough to not abandon the tracks rail. Electric is all or nothing (not 100%,but close) in that if even a small line isn't electric you only run diesel engines so you can run trains one that one line.
It is easier to load and unload without electric overhead.
Still if the cost of diesel went to $15/gallon the us would put up those wires, but until then diesel is cheaper. Don't forget to adjust for inflation.
maybe this is an incremental strategy plan: have battery power and future ability to also use wires, so that you can operate in situations where there is less than 100% coverage
There are around 300,000 km of active rail in the US, essentially none of which is electrified. Then there are 10s of thousands of diesel locomotives that would need to be all replaced. This would cost trillions of dollars, more than any reasonable estimate of rail revenue for the several decades. Then those overhead wires would need to be maintained, which is much more expensive than just keeping rails functional.
There's almost certainly a power law applying to which tracks are getting the most use. If you can electrify 50% of traffic you would make a great upgrade, and it wouldn't require anything near 150,000km of track.
The operational complexity is nontrivial. You would need to attach both diesel and electrical locomotion to every train that has even a small segment in unwired territory, which would be most runs, in exchange for relatively small fuel savings.
Aren't they diesel-electric though? It's not like a diesel engine is turning the wheels. The diesel is just power the electric motor driving the wheels, or are these not the norm?
Yes but the expensive part of the locomotive is either the diesel generator or the equipment to take power from overhead wires (on-board inverters and the pantographs). It's not generally practical to convert one to another.
UP is a freight railroad and has around 32k miles of track, and about 10k trains. Also, they need to operate 24/7 in harsh conditions all throughout the US, west of Mississippi river, so very hot and cold, mountains, desert ect.
How does the overhead wire adjust height to compensate for varying car heights in the case of double stacked intermodal cars? An overhead cable is a limiting factor.
It needs to be high enough to clear the tallest cars (plus enough distance to prevent arcing), and then the pantograph pickup on the locomotives needs to be tall enough to reach the overhead wires.
You missed the point, that those locomotives will only be used in the yard (shuffling wagons). It's not gonna work to long-haul using battery power (too low power density).
It feels like moving around a fixed urban area rather than travelling at high speed through mostly empty areas is probably the more impactful place to remove ICE engines.
Similar to how electric busses usually get assigned to the start-stop routes in the urban centres.
I wonder what the economies are of splitting the difference between total electrification and battery power.
Strategically-located sections of electrified rail to charge trains as they pass through without stopping. Retractable catenary so still compatible with existing clearances. I'm sure someone has had this idea before.
You might not need nearly so much infrastructure, but you invite bottleneck congestion.
The sheer vastness of rural America does not lend itself to using overhead wires. In Europe, a bout of bad weather will tear down the wires in multiple places and make the line unusable even though the tracks themselves are fine. It is always "fun" to commute after a night of heavy wind, but at least the countries here are mostly compact and the locations that took damage are close to one another, so a few crews can fix them in a day or so.
That would be much harder in the flyover country. I am not sure how the Russians keep up their Transsib line; it is long, electrified and goes straight through thousands of miles of wilderness.
My father in Belarus in eighties and nineties used to travel few times per week about 35 milles in one direction by a local electric train with overhead wires (called "elektrichka" in Russian). Not a single time the train was cancelled. Even delays more then 10-15 minutes were extremely rare including on the days with heavy snow or strong wind. Even all maintenance were done at night and never disrupted the traffic.
So if 40 years ago Soviet Union managed that, I am sure US should be capable to build electrical lines that are not destroyed by a bad weather.
Belarus doesn't get winds as strong as western Europe. Other weather is worse (heat and cold).
I think the GP comment was wrong anyway. The trains are delayed due to fallen trees and landslides much more frequently than damage to the catenary. (And neither is common enough that you'd think about it.)
In photos from the USSR, I noticed that forests around the railway tracks are cut down in a pretty broad strip, perhaps 100 m wide?
This is an efficient countermeasure against the trees falling on tracks and taking the wires with them, but some countries aren't willing to cut down that much of a forest.
Not in the U.S., it isn't. There's not much forest left in the interior of the country that wouldn't be snapped up for residential real state if it weren't already privately owned for logging or as National Forest/National Park acreage. Or, it's so mountainous that it would be impractical to use for railways.
Clear cutting an acre gives you about $1500 for wood that took 20 years to grow. This is not an intensive industry in terms of what it generates per acre. I don't see how you are going to have to pay a lot to keep a strip clear on either side of the railroad. $75/acre/year would seem to be enough.
Ah interesting, I was actually thinking less about the cost for the maintenance but rather the cost for land acquisition. Even with imminent domain you're going to be fighting lawsuits for years, if there's any real infrastructure built in the new area you need that's going to be quite expensive to acquire and tear down, etc. but maybe they're already zoned out from building that close to the tracks
The context up-thread is removing trees in a wider strip to avoid them falling on the cables and tracks. It's not about tearing down buildings, which tend not to fall over in the wind.
You've got that right. A sensible passenger train that runs north/south along the Rocky mountains? That would be too easy.
I though taking the train from Montana to Utah would be nice break from driving it - then I saw the only route was to go out to the coast, down the coast and back inland. What should be a one day trip takes three.
Maybe improving rail emissions should be a very low priority, because:
* It's already the most CO2 efficient way to move freight.
* It's also one of the things that's going to be hardest to improve.
Little steps like considered here: battery-electric locomotives for use in rail yards-- make a lot of sense. There may be some specific rail lines that lend themselves to overhead electrification. And otherwise, maybe the focus should be on moving more goods transport to rail instead of making rail more CO2 efficient.
Switzerland is around 40,000 sq km to the US’ 10,000,000 sq km. I don’t think you understand the scale of what electrification of lines in the US would mean.
The relevant metric is population vs rail line length. Switzerland has 8.4M people for 5.7k miles of railway. The US has 335M people for 294k miles of railway. The difference is not too crazy. The total scale is different, but the true problem is probably something between economics and politics. My guesses would be that (1) Swiss railways are pretty much run as a public utility. (2) Swiss railways prioritize on passenger rail, which means more rail near population centers. Diesel is not ideal near population centers. (3) Electrification of rail has been a Swiss priority for a long time, so the marginal cost to add it to new rail installations is low.
This depends heavily on the density of operation; globally at least for heavily used lines the total cost of operation (infrastructure, locomotion, etc.) is much lower for electrified lines, in no small part because each locomotive needs much less maintenance.
From that regard, it's somewhat surprising that none of the busiest lines have been electrified.
Not the first “fireless locomotive” to see service in railyards. Historical versions ran on steam reservoirs or compressed air, replenished by a central power plant. Some are still in use today:
It's almost certainly possible to create dedicated "battery cars" to extend the range of these locomotives enough to use them on long-haul trains. I expect the only downside of that today is cost, but as batteries get cheaper it will probably become a common thing.
Only if they can be charged. Many rail yards are in remote locations. A battery-powered train is useless if you are charging it using diesel generators because your rail yard doesnt have enough grid capacity.
Does anyone know who's manufacturing these locomotives? I'm surprised they didn't name a manufacturing partner. I have to assume it's not a US company.
> The railroad will spend $100 million on the Progress Rail-built locomotives and other infrastructure improvements, the largest investment into the technology ever made by a Class I railroad.
Switching to fuel cells would only achieve a slight efficiency improvement; large diesels are pretty efficient.
Trying to maintain hydrogen fuel systems in railroad environments would be a nightmare; hydrogen leaks out of everything. What it doesn't leak out of, it embrittles.
Fuel cells require ultra-pure source gasses, not something you really find in railroad environments.
It seemed like the future 2-3 decades ago but it just hasn't matured sufficiently, and we'd have to develop an entirely new production and distribution chain for it.
Leaks -- yes, but it's much easier to maintain in regularly professionally maintained commercial-only bulk equipment, than in personal cars and garages.
Embrittlement is a known problem, and pretty much any alloy of steel helps against it. Various coatings are used as well (e.g. organic compounds). It's a well-researched area, so it's possible to estimate and engineer around it.
Re. ultra-pure source gasses, I don't know, maybe, but I don't see any difference with gasoline or Jet-A fuels. Airports aren't ultra-clean environments either.
Well, that at least explains why they laid off so many of their private security personnel, and then helped shaped the "LA train crime" story to their advantage. Those battery-electric locomotives are not cheap.
[ EDIT: have any of you downvoting this actually read the backstory to the LA train crime story? Here are some links to the layoff part:
> Union Pacific plans to purchase 20 battery-electric locomotives for yard service
If all they're doing is moving around a yard, they're not ever very far from a charging station and they're moving at very low speeds.
"Replacing" may be just that. Few locomotives are built for yard work today. Most US switchers are old road locomotives, often half a century old. Sometimes they have a new power package. Progress Rail started as a locomotive rebuilder, changing out power packages for new ones, usually Caterpillar Diesels. Their electric seems to be a repower job of a classic General Motors Electro-Motive Division GT. Here's a video of their standard new Diesel repower job.[1]
Lithium iron phosphate batteries, at least in the Progress Rail version. The heavier weight of lithium iron phosphate is a feature, not a bug, in a locomotive. Locomotives are built heavy to improve traction.
The end result is not just a yard locomotive. Some of these are in test elsewhere for short-haul lines. Range maybe 300 miles.
Another boring, but useful, technology, from old-line industrial companies. This is what makes the world go.
[1] https://www.youtube.com/watch?v=6Kth3i2PGE0
Here in Germany, we still build new models of railway shunting engines such as the Voith Gravita [1], and we have nearly a thousand (!) of the old V60 in service [2]. Normal open-track models may have superior fuel efficiency at higher speeds, but commonly lack the from-zero traction capability of a specialized shunting engine.
[1]: https://de.wikipedia.org/wiki/Voith_Gravita
[2]: https://de.wikipedia.org/wiki/DB-Baureihe_V_60
How expensive is a 10MW electric motor? Asking for a friend
Edit: for context - Tesla Semi is just 4x 250kw motors
Not really. You can't use the electric side of a locomotive drive train anywhere else than in a locomotive, and for fully electric locomotives you can't even use the transformers in any non-railway setting simply because the frequencies used are generally incompatible with usage on the normal power grid. Old electric locos sometimes are used to provide auxiliary power for parked cars [1], though that has fallen out of fashion here.
What is commoditized is the engine side of a diesel locomotive, that's your run-off-the-mill CAT, MTU or whatever industrial diesel engine. As long as it fits into the locomotive body and accepts a hydraulic or electric generator at the output, it can be used. IIRC there even were some experiments with gas turbines on French high-speed locomotives, but these had atrocious fuel economy.
> Is it a single motor or one per axis?
That entirely depends on the engine model, and can be inferred from the wheel arrangement code [2].
[1]: https://de.wikipedia.org/wiki/Trafostation_(Elektrolok)
[2]: https://en.wikipedia.org/wiki/Wheel_arrangement
This locked-together wheel drive is a huge win. No more wheel slipping and spinning. Wheel slip has been a huge headache with locomotives back to the steam engine era. The effect is to almost double drawbar pull. Starting heavy trains on upgrades now works much better.[1]
There are many other classic ways to build locomotive drivetrains, but this won out.
UP 4014 "Big Boy", biggest working steam locomotive: 135,375 pounds tractive effort.
General Electric ES44AC, common road locomotive today, over 3700 units built: 183,000 pounds tractive effort.
Dull, boring, from old companies, and very effective.
[1] http://www.republiclocomotive.com/ac-traction-vs-dc-traction...
This is a surprise, because it calls to mind this old story:
https://gizmodo.com/that-time-a-canadian-town-derailed-a-die...
Was this simply an unusual locomotive, and therefore compatible with the grid? What's going on?
In this case they took MLW M420W locomotives and just straight hooked them right up to the local grid.
From the article it sounded like it wasn't ideal(there was damage to the gearbox from driving the engines down the road).
(as an aside this is why I think a diesel-electric tractor or pure electric would be pretty nifty thing)
Electric motors on tractors are an absolute rarity (usually, the motors need cooling, which is in conflict with the wheel/tracks being rated for driving through water and mud).
The usual is either direct drive or using the hydraulic generator for the power tools and actuators also for the drive train... and you can get electricity generator packs that you can simply plug in into the hydraulics port for a power tool [1].
[1]: https://hk-hydraulik-kontor.de/de/147440-Hydraulik-Generator...
The diesel prime mover is usually an EMD or Wabtec/GE engine in the US - very few mainline locomotives use anything else. They are medium-speed engines and two-stroke (EMD) or four stroke (Wabtec/GE with some EMD Tier-4), built to be reliable, cheap and nearly indestructible. You can swap other engine makes in, but usually with worse reliability and performance.
Outside the US other engine makers are more prevalent, but interestingly US engine designs are the most numerous (except in former Soviet states and China). In the US, newer non-road engines may use Tier-4 MTU or CAT engines for eco friendly power, but they're still the exception and not the rule.
[0] https://en.wikipedia.org/wiki/Siemens_Charger
A bit off topic, but I find it mildly amusing that most of the article is taken by the huge table that is entirely about steam loco wheel arrangements, and moreover all of those various arrangements actually have their own article! Rather thorough for a decidedly obsolete technology.
The traction of a DC drive vs AC drive is significantly different(the below article cites at least 2x better for AC) in part due to the fact that a DC motor will "run away" once it breaks the static friction limit where a VFD(holding a fixed frequency) will self-correct as the wheel overspeeds and is slowed down by the other side of the magnetic field. Since most EVs use AC VFD a lot of that same development can be applied in traction applications.
[1] http://www.republiclocomotive.com/ac-traction-vs-dc-traction...
https://www.up.com/aboutup/special_trains/gas-turbine/index....
They're great for stopping (relatively) quickly on level ground. But not so grest for controlling your speed.
Big diesel-electric locomotives have large, actively cooled resistor banks, usually on top of the engine. When rolling down hill they run the electric motors as generators, and dumping the energy into the resistor banks.
The mechanical brakes can't absorb that much energy - they'd wear out after a few minutes.
It seams like a resistor on a generator would just be a breaking load, and not actually capture any power.
This is from 2012 but still relevant and why we don’t have electric commercial passenger planes, and probably never will until we make 10x gains in energy density:
“”” Stored energy in fuel is considerable: gasoline is the champion at 47.5 MJ/kg and 34.6 MJ/liter; the gasoline in a fully fueled car has the same energy content as a thousand sticks of dynamite. A lithium-ion battery pack has about 0.3 MJ/kg and about 0.4 MJ/liter (Chevy VOLT). Gasoline thus has about 100 times the energy density of a lithium-ion battery. This difference in energy density is partially mitigated by the very high efficiency of an electric motor in converting energy stored in the battery to making the car move: it is typically 60-80 percent efficient. The efficiency of an internal combustion engine in converting the energy stored in gasoline to making the car move is typically 15 percent (EPA 2012). With the ratio about 5, a battery with an energy storage density 1/5 of that of gasoline would have the same range as a gasoline-powered car. We are not even close to this at present. “””
https://www.aps.org/publications/apsnews/201208/backpage.cfm
For freight in the US, the worst case segment I know about is ~700 miles. This can be handled with about 400-500 feet of battery cars, which is probably 5%-10% of train length. So the worst possible scenario is pretty close to feasibility with current tech.
If railroads were to start investing in this level of battery, beyond saving a lot of fuel costs, they'd have a couple hundred MWh of battery at every rail station. This would be a significant grid asset, at least at the moment. In a decade, that level of storage is probably going to be extremely common. But in any case, there's significant opportunity for demand response payments, if not using the batteries for replacing peaking power on the grid.
Rail is 2% of transportation emissions, which is 29% of total US emissions [1], which was 6.558e6 metric tons in 2019 [2]. So rail is 3.8e7 kg of CO2 emissions. Diesel emits 10 kg/gallon [3], so that's 3.8e6 gallons, and at a cost of $3/gallon that's only $10M dollars out of what is an $80B industry [4]. That's so vanishingly small that I wonder if I have done something wrong here...
[1] https://www.epa.gov/greenvehicles/fast-facts-transportation-...
[2] https://www.epa.gov/ghgemissions/inventory-us-greenhouse-gas...
[3] https://www.epa.gov/energy/greenhouse-gases-equivalencies-ca...
[4] https://railroads.dot.gov/rail-network-development/freight-r...
That's in line with my initial expectations, and cutting fuel costs by even, say, 30% could be a big win.
https://www.flyingmag.com/alice-electric-commuter-airplane-p...
For larger airliners there could eventually be a role for plug-in hybrid propulsion systems. Use a fairly small battery pack and electric motors to augment the turbines during take-off and climb, then switch them off during cruise. There would be a weight penalty but it might deliver a net fuel savings for shorter flights.
Example: https://www.reuters.com/business/autos-transportation/when-d...
I remember having a heated discussion with someone about this at work, and it came down to where you were charging that Tesla and if you had rooftop solar (not even discussing the environmental impact of mfg + shipping + installation + support + useable lifetime of the solar panels, home batteries, and support accessories).
And at the end of the day, moving around a 5000# Tesla or 6500# F150 Lightning takes a lot more power in any form than a 3400# Civic / Camry.
There are also isolated use cases that the US railroads have been electrified for in the past (a lot of it was de-electrified to artificially boost revenues with asset sales in the midcentury). Namely
* mountain tunnels; a fair amount of Western mountain tunnels can only accommodate one diesel train at a time due to ventilation, and the crews carry respirators and oxygen in case the train stalls inside
* any sort of long sustained slope; downhill trains using regenerative braking can return electricity for those going uphill
Almost certainly. But this probably evaporates once you need to pull significant amount of battery.
Sure. But you also need a whole lot of them to provide sustained power to move a large train for a decent trip length.
> especially if they can dump power into the grid (or battery) when braking
Smaller benefit here to regen. Sure, a 10000 tonne train has a lot of kinetic energy-- maybe 3 gigajoules or something. But compare to > 50MW to keep that train moving at a decent clip. So a complete stop with 100% of the energy recaptured is only about 60 seconds of rolling resistance energy use.
It may be good for some segments, but consider the number of charge cycles and charge/discharge rate, along with the peak charging currents on the overhead lines.
For, say, 10000 tonne trains, 15MW sustained is a good very optimistic target for how much power you need to put out to keep rolling (before you make this any worse with adding battery mass and before you consider e.g. slopes, braking, etc).
If your goal is a discharge rate of C/1, you're carrying 75 tonnes of batteries-so it masses about 1% more.
Then, what duty cycle are you charging at? 100% coverage from the overhead power lines means you need to bring 15MW into the train. If the goal is a big saving in the amount of overhead power lines needed, 10% coverage from the overhead power lines means you'll instead need to bring 150MW into the train during those spans (and, this is a really aggressive 10C charge rate...)
I think C/1 is too aggressive for good cycle service, 10C is waaaay too aggressive for charging-- and these are best case scenario (flat ground, etc). If you multiply the amount of batteries by a big amount, now the mass change to the train and the rolling resistance contribution to the train from batteries becomes significant).
edit: in the end, I think you're usually better off just electrifying the portions of the train route where it's easiest, and burning diesel the rest of the way, instead of trying to somehow dotted-line-overhead-electrify things and limp through with batteries.
The Pareto principle means that even if battery capacity means you need 80% or 95% coverage you could still see large savings over a 100% electrification.
Remember that you can also coast. If it's just about a low bridge or short tunnel you might lower the pantograph a few 100 metres on either side of the bridge. No need to wear the battery at all for such a short stretch - even with the brakes fully applied the train takes about a mile to stop. Trains don't currently do this because they don't have sophisticated position-based pantograph control and if they had to do an emergency stop under the bridge they would be stuck, but with more advanced control computers and battery backup both those problems can be solved.
Where I live they are electrifying 150 miles of track. This means 85 bridges need to be raised, demolished or rebuilt, and it's a big part of the cost. And Denmark is pretty flat - there are no tunnels as far as I remember.
> The locomotives are 3-4MW peak and I rarely see them use more than 3 or 4 of them on a train.
3-4 locomotives is typical for a "small" 3000 tonne train.
When you get to the 10,000 tonne monsters, you might have 8 GE Evolutions distributed, capable of 24MW sustained.
It's also worth noting this is not really enough. If rail freight was a little faster, it could be used for more things.
> 50%, which is totally doable
The US rail freight market and scale is different from Denmark. I don't think you understand how much goods travels over track which is near nothing and very long. Especially in the Western US. E.g. Los Angeles to San Antonio is just one of many major rail route. It's through 1200 miles of largely desert with nothing around. Estimates are that it would cost $5M/track mile to electrify.
Just to note the scale difference: Banedanmark moves about 2.6 billon tonnes-km according to Wikipedia. BNSF and Union Pacific railroads-- the #1 and #2 rail freight carrier in the US-- move about 1500 billion tonnes-km.
On the other hand, it takes about 12L of diesel to pull a tonne of freight across the distance.
We'd be far better off trying to just move more freight to the existing rail network than to try and electrify it, if we're looking at things from a standpoint of reducing CO2 emissions.
Don't misquote me, dude. Here's what I wrote:
> for 50% coverage charging speed falls to 1C, which is totally doable
I was saying that it's doable to charge batteries at a rate of 1C.
Sorry-- When I quote from earlier ones I lose the window and I sometimes screw up quoting.
ON THE OTHER HAND, you seemed to imply 95% electrification was plausible... so I don't think I got the spirit of your comment wrong. If 50% isn't even plausible, then it's all a bit moot, isn't it?
[Also, note that if you have 50% coverage and are charging at 1C, you're also putting 1 cycle on the battery per 2 hours].
I think you're generalizing from a small market, with much less rail in empty space, to a massive market, with lots of rail in empty space, that moves a very large chunk of goods by rail.
And I agree it really varies where you live and other variables, but that to me doesn't matter when 1) ICE vehicles aren't really that efficient anyway. 2) Even ignoring the first point, it's possible electric vehicle owners are more likely to get much of their electricity from greener sources than non-electric vehicle owners, and the extra demand on the grid requires more energy production to be built, and new energy production is probably going to be a lot greener than old sources. 3) A lot of people are somewhat environmentally conscious but only as convenience and their current lifestyle allow. People know a Civic is probably more environmentally friendly than 99% of cars, and don't care.
Then you can get in how many oil spills have been prevented, etc.,
High-temperature gas turbines can also have efficiencies over 50%.
Modern four-stroke internal combustion engines used in cars and trucks can have an efficiency over 40%, up to 45%.
That said, such efficiencies remain low compared to electric motors with efficiencies over 95% and with combined cycle power plants which can reach an efficiency of 65% (while power plants with heat cogeneration may reach efficiencies around 80%).
Includes energy and emissions calculations that take into account embedded costs.
Might also search for Sustainability Engineering.
This sounds like a faulty analysis.
Generally even if 100% of your electricity is something moderately bad, like natural gas, end-to-end power use is better than an ICE with gasoline.
Figure an electric car is 150 watt-hours per mile, and charging is 94% efficient (pessimistic, but makes the numbers round). Natural gas is 0.4 kilograms/(KWhr), so about 65 grams of CO2 emitted for that mile. Compare to 8.5 kilograms of CO2 emitted from burning a gallon of gas, so you'd need to get 130 miles to the gallon to be equivalent.
Considering lifecycle costs makes things closer, but not super close.
> and if you had rooftop solar
Most people charge at night, so your own rooftop doesn't help. (Also, most places the renewable mix is worse at night, but not in all: in some places wind and hydroelectric "win").
> And at the end of the day, moving around a 5000# Tesla or 6500# F150 Lightning takes a lot more power in any form than a 3400# Civic / Camry.
More mass means slightly more tire friction and means more kinetic energy-- a big fraction of which you get back in regen.
Obviously electric requires infrastructure too, but it would be good to see a full breakdown and I can’t find one.
Electrifying US rail outside of switchyards won’t ever be practical, unless you could drive down the cost of electrified tracks with a third rail (overhead electric at this scale would be obscenely expensive).
Why is that? Russia, a considerably poorer country beset by endemic corruption and other major issues, has managed to electrify the 9000+ km (considerably longer than any coast to coast US railway route) Trans-Siberian railway. With overhead lines, obviously.
Personally, I would prefer electrified freight rail, I’m just unsure if the US knows how or can do it. I suggested third rail if the cost came down because in America, you can usually coax towards the right solution if you can show drastic cost savings/reductions (see the rapid renewables uptake as costs declined over the last decade). At a glance, it seems easier to throw down a third rail while doing track work versus the construction effort for thousands of miles of overhead gantries and 25kv power lines. You could pair this with HVDC transmission lines looking to use railroad right of ways to avoid NIMBYS (the SOO HVDC line in the Midwest, for example [4]), for power accessibility.
[1] https://www.nytimes.com/2021/11/28/us/infrastructure-megapro...
[2] https://www.nationalgeographic.com/science/article/mega-proj...
[3] https://www.vox.com/22534714/rail-roads-infrastructure-costs...
[4] https://www.soogreenrr.com/about/
Texas Central also seems to be making progress on Dallas-Houston high speed rail.
That said, I agree that the taxpayers don't feel like giving billions of dollars to BNSF and Union Pacific, so they probably won't electrify until there is no other option. Fuel costs just aren't high enough to make it profitable, and the environmental externalities are still free. (But, of course, you'd rather see a 500 car freight train burning fossil fuels than 500 tractor trailers driving down the interstate burning fossil fuels.)
(There are lots of things working against CAHSR. The route has been chosen politically rather than to minimize SFO-LAX travel times. Given infinite budget, you travelers on that route don't want to go through Bakersfield, as it's out of the way. And, the SFO/LAX city pair is already not a particularly optimal pair, it is kind of reaching the high end of distances that make high-speed rail the best travel option. That's why I look at Texas Central and Brightline for models of what to do in the future. Texas Central is a really good city pairing, in a region where their 16 lane highways can't handle the traffic volume. But I temper my enthusiasm in that not a lot of construction work has been done; I can't find any updates newer than September 2021 when the CEO said pessimistically that there is only a 50/50 chance that construction will start in the next 6 months. We're near the end of those 6 months.)
Currently half of the work going on right now is grade separation that includes both the future high speed rail line and the current freight rail line. So there is some method to their madness. The grade separation provides immediate benefits.
Lot of info linked here https://www.buildhsr.com/
They don't need to be convinced to spend money. They are spending more than ever. But you're dead on about it all being crisis-driven now. Or maybe it always was? WWII was clearly that, then the cold war/space race, then Star Wars, then GWAT (or GWOT?) -- Global War Against/On Terrorism, and now Covid - Build Back Better. Crisis spending is perfect cover for pork and grift, because anyone who questions it can be painted as unpatriotic.
In any sufficiently big project, I'm coming around to the opinion that there's some amount of timeline that results in an effective "never".
I think it's just that at some point, people stop caring? Or at least feeling like they have any motivation to hustle?
And once that happens, the end result in lethargy and a grinding halt to actual progress. Even if checklist items seem to be getting ticked off.
But imagine a train that can go for a kilometre or two without power lines, because it's a hybrid. Suddenly every low bridge and most tunnels are handled by just lowering the pantograph (power pick-up) as you go under them. If lines cross in strange ways or go under buildings you just don't put power lines there. At level crossings you skip the power lines, so no tall trucks will hit them.
I think there are probably huge savings to be made by putting the power lines in the easiest places and bridging the rest with hybrid. The battery recharges at speed as soon as power returns. You can even install a small diesel motor on the locomotive that has enough power (with gearing?) to creep to the next overhead power line if the train is unexpectedly stranded.
When a power line is downed by a tree (or a cable thief), the cleanup crew just removes that section. It is put up later when the backlog from the storm has been cleared.
Of course you need the train to know its location and have an updated list of where to lower the pantograph. That seems to me like a totally solvable problem in 2022. It's like 100 times easier than a self-driving car or landing a rocket with retropropulsion.
* Double stack well cars sit very low. There are currently no third rail installations in the US that wouldn't get sideswiped by a well car. So their installation would basically mean forgoing half of freight revenue.
* Third rails have to operate at lower voltages due to the fairly small clearance to the ground, and so they require more frequent substations than higher voltage overhead wires.
Edit: excellent resources, thanks all for replying.
Which is why third rail systems are usually only seen in metro lines and similar. I'd guess in urban environments sprinkling more substations around isn't such a huge issue, as access to the power grid is seldom an issue. Also metro trains need much less power than a high speed passenger train or a heavy freight train.
generally speaking, third rail allows for a smaller tunnel diameter than overhead systems. (third rail is located near the wider section of tunnel in the middle whereas overhead requires extending the height.)
Anyone building new tunnel should allow the little extra room for overhead, but retrofitting may not be worth it.
This would probably be the way to go if the US would introduce electrified rail routes.
An overview of Third rail vs. Overhead Wire from a transit perspective, but it's similar with freight https://www.youtube.com/watch?v=LGI9XuHE3P0
TLDR:
Grade crossings are more complicated, if not impossible
Smaller voltage since it's closer to the ground and the grounded rails.
Thus higher current & more losses, needing more power stations.
This is probably way worse for freight, since it weighs more and there are long gaps between civilization on the routes.
The other big problem (in addition to the ones you've outlined) is that having miles of live conductor at ground level isn't particularly safe - for track crew, trespassers, or wildlife.
Britain has essentially stopped installing third rail for all these reasons. It's all 25kV overhead now.
And the same issue also applies to every instance of pointwork.
India has electrified almost 50,000 kilometers of track with overhead wires and this is increasing eabout 5000 km a year. China has almost 100,000 km of electrified rail track.
So very likely whatever barriers to electrification there are in the US are largely self inflicted and maybe corruption or regulatory capture driven.
https://news.ycombinator.com/item?id=30113639
Left unstated is whether the diesel-electric locomotive in the consist could recharge the batteries of the battery-electric locomotive as the train is rolling. I expect it could but it's probably pointless because it's more efficient to let the diesel-electric pull the train.
[0] https://www.youtube.com/watch?v=zIgmNOxa5aI
Also, while reduced fuel consumption is nice, another major beneficiary would be the environment, specifically when operating in urban centers. I’ve lived near heavy-use railways and currently a switching yard for most of my life, and some days the diesel exhaust is quite strong, depending on the prevailing winds. The engines are usually pretty clean burning for the amount of work they produce, but not always…
But you see, they don't care. If there is no incentive for them to do it, why would they? Good neighborhood-will will pay for a donation to a local charity cause, etc, but will not make meaningful expensive changes to the SOP.
Ideally this is the point where a regulator (of some kind) steps in and nudges the change. We all know what the political problems behind that are - despite mounting evidence of how damaging diesel exhaust particles are to us, and our children.
Side note on supplying power to battery-electric locomotives from overhead wires (via pantographs): The railroad industry has a lot of experience with pantographs, overhead wires, and the infrastructures needed to power said overhead wires. That stuff is expensive to build and maintain. And if your RR depends on it, then you can be utterly screwed when a large blackout occurs. Or (say) when all the power lines in an area have to be turned off, because the wildfire danger level is too high.
At the same time... the performance benefits really aren't worth it for freight trains. Remember that diesel locomotives are already an electric drivetrain--the diesel is merely fueling a generator that's sitting on board to power the drivetrain. The big savings with electrification come with weight reduction--and with freight, the weight of the locomotive is a small component of that weight--or using EMUs that let you have every wheel being powered (and with freight cars, that's again never going to happen).
According to this study from 2012, the cost of electrifying railroads in California is about $4.8M/track mile, and according to google, there are about 140,000 route miles of freight rail in the US.
I'd assume that doing this in bulk might drop the costs substantially, but we're still talking about a huge network.
American infrastructure projects tend to be super big, then don't do anything for 10+ years before you kickstart everything up again. This is a fairly poor idea if you want to keep knowledge around from the last time it was done.
Amtrak is currently investing in dual-mode locomotives: https://www.trains.com/trn/news-reviews/news-wire/amtrak-sie...
My understanding of how these work is that when not connected to wires directly, a diesel generator supplies electricity instead. So partial wiring is possible with these. Amtrak has some additional constraints (they can't run diesels under the Hudson River) but to some extent a lot of freight operators have similar restrictions but deal with them differently; due to ventilation concerns, most Western mountain tunnels only permit one train in them at any given time, and the crews have to carry respirators and oxygen in case the trains stall inside the tunnel.
---
Britain also has trains that do this running with a program of incremental electrification: https://en.wikipedia.org/wiki/British_Rail_Class_802
Once the electrification is complete, the equipment can be converted to full electric operation simply by unplugging the diesel generators.
https://en.wikipedia.org/wiki/California_High-Speed_Rail
https://en.wikipedia.org/wiki/History_of_California_High-Spe...
That's not really a big challenge; this is something done globally on a daily basis. Typically you either have an entirely unelectrified siding and shunt in/out of it, or you have only the near end of the siding electrified and propel the cars into the siding.
For the busy routes it would still be worth it, but the is a lot of used just often enough to not abandon the tracks rail. Electric is all or nothing (not 100%,but close) in that if even a small line isn't electric you only run diesel engines so you can run trains one that one line.
It is easier to load and unload without electric overhead.
Still if the cost of diesel went to $15/gallon the us would put up those wires, but until then diesel is cheaper. Don't forget to adjust for inflation.
You missed the point, that those locomotives will only be used in the yard (shuffling wagons). It's not gonna work to long-haul using battery power (too low power density).
Similar to how electric busses usually get assigned to the start-stop routes in the urban centres.
Strategically-located sections of electrified rail to charge trains as they pass through without stopping. Retractable catenary so still compatible with existing clearances. I'm sure someone has had this idea before.
You might not need nearly so much infrastructure, but you invite bottleneck congestion.
Nevermind how vastly more expensive MOW costs are for electrified lines.
That would be much harder in the flyover country. I am not sure how the Russians keep up their Transsib line; it is long, electrified and goes straight through thousands of miles of wilderness.
So if 40 years ago Soviet Union managed that, I am sure US should be capable to build electrical lines that are not destroyed by a bad weather.
I think the GP comment was wrong anyway. The trains are delayed due to fallen trees and landslides much more frequently than damage to the catenary. (And neither is common enough that you'd think about it.)
https://www.esa.int/ESA_Multimedia/Images/2018/01/Wind_speed...
This is an efficient countermeasure against the trees falling on tracks and taking the wires with them, but some countries aren't willing to cut down that much of a forest.
https://www.forest2market.com/blog/how-much-money-is-an-acre...
I though taking the train from Montana to Utah would be nice break from driving it - then I saw the only route was to go out to the coast, down the coast and back inland. What should be a one day trip takes three.
* It's already the most CO2 efficient way to move freight.
* It's also one of the things that's going to be hardest to improve.
Little steps like considered here: battery-electric locomotives for use in rail yards-- make a lot of sense. There may be some specific rail lines that lend themselves to overhead electrification. And otherwise, maybe the focus should be on moving more goods transport to rail instead of making rail more CO2 efficient.
From that regard, it's somewhat surprising that none of the busiest lines have been electrified.
https://en.wikipedia.org/wiki/Fireless_locomotive
https://www.progressrail.com/en/Segments/RollingStock/Locomo...
The batteries are 1,800 kWh or about 18,000 kilo-Teslas.
Progress Rail is at least building them.
https://www.progressrail.com/en/Company/News/PressReleases/C...
> Union Pacific Railroad will purchase 10 battery-electric locomotives from Progress Rail, a Caterpillar Company.
Trying to maintain hydrogen fuel systems in railroad environments would be a nightmare; hydrogen leaks out of everything. What it doesn't leak out of, it embrittles.
Fuel cells require ultra-pure source gasses, not something you really find in railroad environments.
It seemed like the future 2-3 decades ago but it just hasn't matured sufficiently, and we'd have to develop an entirely new production and distribution chain for it.
You're just outdated on your info.
Embrittlement is a known problem, and pretty much any alloy of steel helps against it. Various coatings are used as well (e.g. organic compounds). It's a well-researched area, so it's possible to estimate and engineer around it.
Re. ultra-pure source gasses, I don't know, maybe, but I don't see any difference with gasoline or Jet-A fuels. Airports aren't ultra-clean environments either.
https://www.reuters.com/business/sustainable-business/gm-sup...
[ EDIT: have any of you downvoting this actually read the backstory to the LA train crime story? Here are some links to the layoff part:
https://jalopnik.com/union-pacific-train-thefts-started-righ...
https://www.lataco.com/union-pacific-theft-police-laid-off/
]