I'm not sure how to word this... and I'm trying to learn. Please give me a little buffer here...

Doesn't the hybrid drive (and CVT) allow the ECU to put the engine in more efficient RPM ranges and use the excess RPM/power to drive the generator for later EV assisted motion? If you're able to stay at an RPM where the engine is (say) 30% efficient and recapture that 5% of efficiency as electricity for future use, are you not being more efficient across the entire system when compared to an ICE only model which we've said was 25% efficient? Sure, once the 5% reclaimed efficiency is converted to electricy/battery and back momentum via the electric motor, you don't get the full 5% back but you are still going to get efficiency that's better than the original 25%.

I'm not saying you get something for nothing but you're just getting more by using the ICE while it's in a more efficient range.

I could be completely off base here so please be gentle.

 

This was my point in a backwards sort of way.

If we had the real numbers we would be able to accurately quantify the differences but since we don't we are running around using noodles and what not to try to tell others.

By the way I love noodles but I am lost using them here.

 

Let me try to referee if I may.

#1 Comparing Diesel Locos to Steam Locos is a bad idea. I have been an avid railfan for 30 years. Steam locos were actually more powerful, and more capable than any diesel loco ever built. EVER. ( like 5 to 6 times more powerful ) And the fuel economy was fair.

ONE 1945 steam locomotive can pull 150 loaded coal cars.
One 2008 diesel locomotive can pull 25 loaded coal cars.

Steam locomotives were also, a mechanical nightmare.
They required daily maintenence. Not monthly!
In 1945 there were more locomotive mechanics, than engineers.

Diesel locomotives are quite large, they are not "one-third the size" becuase of the electic drive. A 1000HP electric drive motor will require a 1200HP diesel motor due to losses. Modern locos are diesel electric because the diesel can run at max. RPM/Horsepower when the train is standing still or crawling, and there is no "transmission" or gear shifting.

#2 I have never met Stan. I do not know Stan. Stan is not paying me to type this. However, Stan is most correct as I see it.

Electric motors are much more efficient at turning energy into motion, which is why you buy a car. HOWEVER any electric motor that is spun with power from a gasoline engine ( aka FEH, Prius ) is never more efficient than running the gasoline engine alone. This is due to the commonly cited, but sometimes not fully understood "laws of physics, nature" etc.

So why are hybrid cars "more efficient" aka get more MPG?
#3 Timing is everything.

It is MUCH more about TIME than watts, calories, joules, btu, or "noodles".
( Nice try, and I applaud your effort, but I don't care for noodles. )

Let me say it again... TIMING IS EVERYTHING.

Hybrids don't get more MPG because they have an electric motor. Really.
They get more MPG than regular cars, because regular cars do zero work when the tires are stationary. The TIME spent at stoplights uses gas, but does zero useful work in a regular car. The TIME a Hybrid spends at a light with ICE on does useful work. It charges a battery, which in turn, can produce work for you later ( taking off from the light). The TIME a regular car spends coasting downhill burns gas, but does zero useful work for you ( assuming the hill is steep enough for gravity to do all the work ). When a hybrid is going downhill, it is often doing useful work, charging a battery for you. When you hit the brakes in a normal car, the brakes make heat, and that heat goes into the environment. The car's brakes do zero useful work ( scientifically speaking ) for you. They are useful, but literally, they are not doing work for you. In a hybrid, the brakes do useful work for you, they charge a battery.

A hybrid is not Not NOT more efficient because of the electric motor. Nope. The hybrid is more efficient because it has a storage device ( battery ) other than gasoline. The hybrid is more efficient because it has a downsized ICE. The hybrid is more efficient because literally, it uses it's time wisely.

If you had a big lead ( lead is massive ) flywheel, and the ICE spun-up the flywheel when you were at a stoplight, or when braking, or when going downhill, you could discard the battery, discard the electric motor, and probably ( almost certainly ) have an ICE car that was more efficient than the one you have now. Just a battery fits into a more convienient package than a giant lead flywheel.

A hybrid is more efficient because the ICE is doing useful work a high percentage of the time, ( aka little idle time ) and a regular car is doing useful work a low percentage of the time ( lots of idle time).

Quote:
"a small efficient Diesel driving a generator which runs the electric motor as being something worth looking into. You would use the battery pack to add power for starts and hills and passing. Otherwise the genny would power the motor."

This is ALWAYS ALWAYS ALWAYS going to be worse fuel-wise. The senario you diescribe will consume significantly more fuel.

Instead of a diesel motor spining your tires, you now have the same diesel motor spinning a generator, electric motor, and wheels!!! This is impossible to be more fuel efficient... and this is why you don't see one on the road today... it would be easy enough to build. What you describe, like in a diesel locomtive, gives you a mechanical advantage ( aka torque multiplier ) but a fuel economy dis-advantage.

Quote:
"If it takes 1/4 gallon to go 10 miles using the ICE ONLY and this is due to it's inherit inefficiency I think that those same KW's "

You don't have kW's. You have gasoline.

are better put to use in powering an electric motor which even being charged by the ICE will go farther due to it's HIGHER efficiency."

False! What you describe would only work if you had a chemical fuel cell, where you went from liquid, chemical gasoline directly into electricity. Any time you "burn" this gas first in any combustion engine and turn it to mechanical energy first, and electicity second, it will always be less efficient, not more.

You must multiply all the steps. And when you multiply percentages, the net result gets smaller, not larger.

Take a 25% ICE and 90% efficient battery, 90% generator, and a 90% traction motor.

Take 100kW of gasoline equivalent.
You could use the ICE only, and put 25kW to the wheels.
OR
You could use 100kW of gasoline equivalent and spin a generator, which charges a battery, which later is used to turn a traction motor.

You have 100kw x 25% x 90% x 90% x 90% = 18.2 kW to the wheels. You are saying this is more efficient than putting 25kW to the wheels with an ICE direct drive to the wheels???

 

I would actually disagree with that statement. On a single unit to unit basis comparison - yes. Sure, you can throw an Alco 2-10-10-2 at a string of cars and it will outdo one diesel-electric locomotive by far. But steam locomotives can only be run in single units. Diesels can be (and usually are) assembled into coordinated multiple unit operations, and at that point they are essentially one unit in operation with any amount of power needed to pull any length of train.

 

Well, you're free to disagree. You're also free to be totally wrong.
I disclosed "railfan" at the start. I know what I'm talking about. I have actually been at the throttle of both a 1936 steam locomotive, ( restored, I'm not that old! ) and a 2003 Union Pacific modern loco...( and many others ) so I know what I'm talking about.

Would you like a photo of 3 steam locomotives at the head end of a 2 mile ( 200 car ) freight? How many photos would you like, since this was common place? Yes, you need 3 engineers vs. 1, since the units were not electronically linked like today... but you can triple or quadruple head steam when needed, and it is quite impressive to see.

It was earlier implied that steam locomotive were not powerful, and modern locos were more powerful. Not true in the slightest. Like you said, you need several ( relatively small ) modern locos to do the work of one large steam loco of yesteryear.

 

Well, you're obviously a steam aficionado and I'm obviously a fan of diesel electrics (train fan since the age of about 8, and had HO layouts in every house I've been in since then that have had basements - including the current one. Never had a steam loco in my inventory), so this could go on forever and never get anywhere.

I guess we'll just have to agree to disagree.

 

After reading John's very informative post, I think I have a better way of wording what I was trying to say.

The FEH is more FE because it has systems in place to recapture the undesirable overhead in a standard ICE-only system. As I see it in a standard ICE only vehicle, there is overhead in forcing an ICE to work across the full RPM range, overhead in non-moving idle time, overhead in non-regenerative braking, and overhead in engine/compression braking. Some (most?) of this overhead is recaptured on the FEH via the hybrid drive train components and used later to power the vehicle or assist the ICE (including multiple start-ups that could be seen as an overhead of the hybrid system).

The FEH ICE is only more efficient compared to a conventional ICE because of the Atkinson-like cycle and the ECU's ability to take advantage of the more efficient RPM zones (once again I could be wrong on the second part of this statement). The EV portion of the FEH is more efficient only if the power used is from the overhead listed above and not if the ICE was used specifically to create the power.

Oh, anywhere I say FEH, please feel free to substitute MMH and this will be directly related to the thread topic.

 

Don't get me wrong, I love both... but yes, steam is way more interesting to me... but building layouts, I know ( in general ) you need to have one or the other... a diesel / steam combo is just.... strange to me!

I love both in real life. My HO collection has about 28 steam locos.
And the cool thing is, many of them were made in the 40's and 50's... before plastics were made, and hence, they weigh a proverbial ton.
No DCC ( yet ).
-John

 

Huh, I didn't know HO scale has been around that long. I guess I always assumed it was mostly Lionel's O until the mid 60's - but I've never really looked into the history of the scales.

I think I've got 8 locos (almost all Santa Fe Warbonnet vintage - haven't bought any new locos since the BNSF merger) and no DCC yet either. Explored it about 8 or 10 years ago - the technology was just getting popular but still emerging about then so it was expensive and at the time a bit of a task to convert a block layout and the locomotives to DCC. I've just never given it a thought after that (plus I haven't done any major work on my layout in about 6 years - no time these days).

 

The "steam vs diesel" debate has been raging on for at least 3/4 of a century now. There is no single answer that one or the other is better or more powerful or whatever.

In general, though, steam's greatest advantage is at speed, where the mechanics and physics of external combustion, evaporative expansion come into play. In other words, steam engines excel at pulling heavy loads at speed. And therein lies the weak point of steam engines, and the advantage of diesel. You need a lot of low-end power to get a train moving, and the inherent torque advantages of electric traction win out here. That's why, a UP Big Boy 4-8-8-4 steam engine (approx. 6-8k hp) might pull into a yard with 120 cars in tow, and then a pair of 1200 hp diesel yard engines walk off with the whole consist to switch it. They've got the low speed advantage over steam.

Now keep in mind that that is just a very basic comparision in general. There are lots of specific examples that could be cited to try and change the argument.

The real reason you don't find steam engines hauling trains today is not only the low-speed pulling disadvantage, but also the maintenance costs. Steamers, as John said, typically ran only a day or two before needing significant servicing. Diesels typically run months before needing major servicing. And the ability to couple up many diesel locomotives and run them as one by just one crew really helped spell the death knell for steam in a competitive environment.

John said,
"ONE 1945 steam locomotive can pull 150 loaded coal cars.
One 2008 diesel locomotive can pull 25 loaded coal cars."

Don't be fooled by this argument. The cars typically found in steam days generally weighed only around 75 tons loaded. Modern coal hoppers, fully loaded, weigh in around 135-150 tons (some grain hoppers are designed for total weight of 158 tons). For relatively flat terrain, a typical coal train these days runs somewhere around 135 cars, 15k-18k tons, and is hauled by just 2 diesel-electrics (8800 total hp or so). A single Big Boy steamer hauling 150 1940's-era cars of 75 tons each is just 11,250 tons. And I really doubt a Big Boy could pull 150 loaded coal gons. Maybe 150 boxcars averaging 50-60 tons each, but not coal.

So, last time I checked, 135 divided by 2 was around 68, which I do believe is more than 25.

Back to the hybrid topic, there are some switching locomotives known as Green Goats that are basically large battery powered electric engines. They have a relatively small diesel engine that runs an alternator used to charge the batteries. They work well when used for switching, because the typical railroad switching process involves a lot of starting and stopping, and a lot of stationary time. The diesel is able to keep up with the battery charging as long as you use it this way. You couldn't take it out on an over-the-road train because you'd exhaust the batteries before too long. The Green Goats were designed this way to be both fuel and emission efficient. Instead of a large diesel engine idling a lot, accelerating and decelerating, with the resultant poor exhaust emissions, you get a smaller, fuel efficient engine running at a much higher efficiency range.

GE has recently demo'ed a hybrid road locomotive that basically is similar to a conventional diesel electric but with additional battery capacity that can be used as traction power. Diesel electrics have had dynamic braking for years, in which the traction motors were used to generate power while going down long grades. The generated power was simply wasted as heat through grids, essentially just a large toaster (some later models of GE locomotives were even nicknamed "techno-toasters"). The hybrid locomotive is an attempt to capture and use some of this energy just like your FEH does. It may not be a lot of captured power at this point due to battery design, but as you well know any that is captured and then reused to provide tractive effort is better than wasting it as heat.