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Just Curious About Electric Cars

03/17/2012 8:00 PM

Hello folks, this may be simple for many of you folks but something dawned on me yesterday. I was watching that commercial for CSX stating that they can move a ton of freight 500 miles on one gallon of fuel. If that is the case then why can a car not be built to do the same, an average car is between one and two tons. It seems to me that instead of messing with batteries to run electric cars, Why not run a generator, which to me would seem to use less fuel and a wider variety of fuels could be used, to run electric motors. Seems to me the technology should allow us to run farther this way in the same general way that diesel electric trains run. I did not get much as far as electrical knowledge in college so this is a bit out of my general knowlege but seems like it would be more efficient to use fuel to generate electric than internal combustion (same basic principle with the valentin technology ingocar that uses an engine to run a hydraulic pump to operate hydraulic motors on the wheels and the car is said to get 170mpg.)

I am just curious regarding this and have no real need I just wantet to pick some brains as to why something like this is not being worked on.

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#1

Re: just curious about electric cars

03/17/2012 8:11 PM

Nope.

An engine can drive a mechanical drive system with much more efficiency than transferring power through a hydraulic pump/motor system.

Locomotives use diesel electric power and can move massive amounts of weight with relative economy.

Economy of scale.

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#2

Re: just curious about electric cars

03/17/2012 8:15 PM

What makes you think their gallon of fuel has the same energy as what our vehicles get or that their engines are of the same design and efficiency as our vehicle engines or that they have to meet any emissions standards or have emissions systems for that matter other than a simple spark arrestor screen in their muffler?

My job is as a fuel tech for the local rail yard and I can confidently tell you their fuel, engines, and emissions compliance rules are not like what the rest of us have to use.

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#3
In reply to #2

Re: just curious about electric cars

03/17/2012 8:27 PM

TMC I do not know what type of fuel they use or that their engine is the same design, I am merely inquiring as to why it is not possible to make a car that runs on a generator rather than battery and use the generator to run the car itself, it seems to me that it would be more fuel efficient than an internal combustion engine.

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#6
In reply to #3

Re: just curious about electric cars

03/17/2012 9:09 PM

The chevy Volt is the best of both worlds...It has an onboard generator that charges the battery pack when the batteries become depleted....Owners report on average better than 100 mpg.....The majority of the time you can run on electric and recharge from home....If you rarely drive more than 30 miles in a day you may only have to fill the 8 gal fuel tank once a year or so....

http://www.chevrolet.com/volt-electric-car/

http://gm-volt.com/forum/showthread.php?6941-GM-should-be-advertising-real-world-MPG

http://www.motortrend.com/features/auto_news/2010/1010_127_mpg_chevy_volt_diaries/viewall.html

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#31
In reply to #6

Re: just curious about electric cars

03/19/2012 10:19 AM

The major problem with the Volt is the Cash. You will not ever recoup the delta in the expenditure, especially when you look at the cost of money. If you're OK with that, that's fine with me. I've driven my 2005 VW Jetta 122,000 miles and purchased about $11,000 in gasoline. I paid $15,500 for the car brand new. I'll be able to spend another $11,000 in gasoline before I even approach the price of the Volt.

Cheers !

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#38
In reply to #6

Re: just curious about electric cars

03/19/2012 12:52 PM

The Chevy Volt also is used just like a diesel locomotive when ever the speed exceeds 65 mph. In that mode (officially called Mountain Mode), the small gas engine drives an electric generator which powers a 2nd motor to assist the primary drive motor. Fuel economy is definitely sacrificed in that mode. One editor of a major magazine published data that revealed 33 mpg for a 80 mph trip. That is really pretty good at that speed!

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#66
In reply to #6

Re: just curious about electric cars

03/23/2012 3:26 AM

We'll talk again when Volts start coming here to die, like Cavaliers. S.M.

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#67
In reply to #66

Re: just curious about electric cars

03/23/2012 5:47 AM

You know why they named them the "volt"?

Because just like with electricity you typically need a lot of them to do anything useful!

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#11
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Re: just curious about electric cars

03/17/2012 10:51 PM

Well first off their fuel is 500 PPM high sulfur marine/locomotive diesel which is more potent than the standard #1 or #2 diesel fuel you buy at the local truck stops. Basically it has more energy per gallon than what the rest of us can buy.

Second large locomotive and marine diesel engines do not have to comply with the same emissions standards that our vehicles do that that again adds more efficiency to their engines.

Third they run high compression huge displacement engines with very low RPM. The engines I have been around produce around 4400 hp at 900 - 1000 RPM with fuel efficiencies approaching roughly 45 - 50% at full load. That comes from simple volumetric efficiency. The more displacement an engine has and the slower it turns the better it converts fuel energy into mechanical energy.

Fourth their drive trains are all electric with generator and drive motor efficiencies around 95 %.

Also depending on what the train is transporting their power to weight ratio can be as low as .4 Hp/ton for a fully loaded grain train up to 6 hp/ton for an empty flat car train.

So take your average car engine with emission compliance that runs in a 15 - 25% efficiency band coupled to a with a drive train with a 90% at best efficiency all powered by a fuel that has about 50 - 75% the energy per gallon as train fuel and do your math from there.

Personally I strongly believe that with the right fuel, the right engine and drive train designed for fuel efficiency opposed to emissions compliance I don't see why most vehicles could not be running at 2 - 4 times their present numbers while still maintaining equal drivability and power that they have now.

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#60
In reply to #11

Re: just curious about electric cars

03/22/2012 9:42 AM

Don't forget the rolling resistance of steel wheels on rail (wasn't it something like 0.06?) and don't the locomotives have regenerative braking also?

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#35
In reply to #3

Re: just curious about electric cars

03/19/2012 12:09 PM

Dudette,

Where does the energy to recharge your battery (at home) come from? Some stinky electric plant perhaps? And what is the charge to your home electric bill add up to? Bet it runs pretty much the same as just using gas to fuel a car...

Some things require two level thinking ~sadly not many people use that trait.

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#36
In reply to #3

Re: just curious about electric cars

03/19/2012 12:33 PM

You're not really serious, are you?

"use the generator to run the car itself"

What makes the generator turn? Please tell me you're joking.

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#41
In reply to #36

Re: just curious about electric cars

03/19/2012 3:20 PM

Lyn, my point is, and again i know little of electrical engineering, if I can run say a 5kw generator for an hour on say half gallon of fuel, and if say I could hook that up to a car with electric motors, and, just for sake of argument I run 20 miles, then I would be 40 mpg. I do not know numbers to do so or if these numbers would even be good but it would, if possible, be better than the 20 I get now. I know, as stated, that there is a vast difference between a train and a car, and that yes, there are quite a bit of difference, my question was simply to get a better understanding. As for the other comments, I think people are getting a bit edgy about this. It was a simple question to perhaps educate myself, yet some of you feel the need to attack a person for being inquisative. I think it was a very good question. for all it matters even 100 miles per gallon would be good. I know about rolling resistance, and economy of scale, i do not need lectured on the difference in momentum once moving and that cars stop and go where trains do not stop as much. It was a simple question to generate some basic understanding. It seems to me it would be smarter to run the motors off the generator than to run a generator to charge batteries to run the car, because you lose power charging, so all I was asking is why is this not done. The reference to the train was simply because the commercial was what got me thinking about it. Electric motors are far more efficient than internal combustion, and because ice run most efficient at a narrow rpm range, it seems more efficient to use that to run a generator and then use the generator to run the motors.... also, did anybody look at the ingocar website, I watched the video by ingo valentin and he seems to have a good bit riding on the hydrostatic car he is developing.

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#42
In reply to #41

Re: just curious about electric cars

03/19/2012 3:55 PM

Shawn,

You have to take into account all the losses you get from every system used to make the vehicle move. And in the case of the ingo car braking too. Electric cars can also utilize regenerative braking.

In the end, the present ICE/transmission vehicle is pretty good for passenger cars of today. That's not to say that something better won't come along, but I haven't see it yet.

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#43
In reply to #41

Re: just curious about electric cars

03/19/2012 4:03 PM

Actually the constant speed engine driving a generator that drives the wheels concept has been around fore very long time and has proved itself to be highly efficient and reliable in the large construction equipment and mining industry. Diesel electric drive tech has been the primary drive systems in large scale mobile earth moving machinery since the 1960's give or take.

Same with warehouse forklift and goods handling tech that to has been a solid proving ground for full electric drive system technology for many many decades now.

Efficient electric drive is not new its just new to public transportation in the private ownership area. If any automobile manufacture wanted to truly win the EV and hybrid tech race all they would need to do is partner up with any one of the electric drive system companies that make the systems for industrial applications. To them a simple automobile drive system would be a very simple stripped down type of system to design.

Given a typical automobile only sees 2000 - 4000 running hours in its life time and at most an hour two or less of use 5 - 6 days a week that pretty soft service work in comparison to even a basic warehouse forklift that gets built to see 8 - 20+ hours run time 6 - 7 days a week well into the 20,000 - 30,000+ running life ranges!

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#4

Re: just curious about electric cars

03/17/2012 8:30 PM

The rolling resistance of steel wheels on steel rails is WAY less than that of rubber on pavement.

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#18
In reply to #4

Re: just curious about electric cars

03/19/2012 1:09 AM

In addition to the huge reduction in rolling resistance made possible by smooth steel wheels on smooth steel rails, much less energy is wasted as heat because of frequent braking, and locomotives pulling (or pushing) trains tend to run for extended periods of time at a constant speed.

It is possible to reduce fuel expenditure very considerably by keeping your tires inflated at the maximum recommended pressure, by keeping the engine and drive train supplied with clean lubricants, and by driving intelligently rather than impulsively.

Also, for short trips, ride a bicycle or walk.

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#28
In reply to #4

Re: just curious about electric cars

03/19/2012 8:58 AM

The rolling resistance of steel wheels on steel rails is WAY less than that of rubber on pavement.
You beat me to the punch.
Ron

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#30
In reply to #4

Re: just curious about electric cars

03/19/2012 10:10 AM

Also, think about the aerodynamics. A freight train is like 100 or more semis all drafting each other about 3 feet apart. They only have one frontal area to push through the air.

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#5

Re: just curious about electric cars

03/17/2012 8:50 PM

Like Tornado said, railroads roll a lot easier. The ad has to be taken with a grain of salt. They probably got that mileage number from a load that was already up to speed, on flat land, under optimum conditions for the locomotive.

I definitely favor hybrids for city traffic. When you are gridlocked, you use no gas, no electric. You move a few feet on electric, very efficient. Going downhill you actually generate power stored in the battery. When needed, the gas motor fires up to optimum operating speed and charges the battery. Much like the locomotives, the gas motor may not even be directly connected to the wheels. (not real sure about that, but it's what I would do for a small car)

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#7

Re: Just Curious About Electric Cars

03/17/2012 9:18 PM

Diesel-electric locomotive sacrifice some efficiency in order to have a standard engine type that can accommodate a wide variety of track conditions, grades, loads, etc. The locomotive could be more mechanically efficient just running diesel power through a transmission, as in an automobile, but the transmissions wouldn't last. In the long run, the diesel-electric is more cost effective.

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#8

Re: Just Curious About Electric Cars

03/17/2012 9:37 PM

While everyone here has contributed accurate information, there is no reason that an automobile could not have the indirect drive configuration of the diesel electric hybrid design of many locomotives. I don't expect that this will be the holy grail of fuel efficiency that a locomotive can reach for precisely the reasons that has already been stated.

IMHO the primary reason that a car will never approach the efficiency of a train is the details of Lyn's comment of economy of scale. The tremendous mass that a train moves means that rapid acceleration and deceleration is impossible. This is why there are train crossing guards and fencing around train tracks. A train always has the right of way because it cannot stop quickly.

Getting back to your point though, there may one day be a combination of indirect drive where an engine drives a generator that produces a consistent mechanical load for the engine to work at maximum efficiency. The electrical energy then either gets stored or immediately used to maintain speed. Technology to do this efficiently in the size of a car though is not there yet because batteries take too long to efficiently recharge or lose to much power when quick charged. Capacitors efficiently take and release a quick charge but even the new ultra-capacitors do not have the same power densities as batteries.

Who knows what the future will bring.

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#9
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Re: Just Curious About Electric Cars

03/17/2012 9:48 PM

"....there may one day be a combination of indirect drive where an engine drives a generator that produces a consistent mechanical load for the engine to work at maximum efficiency. The electrical energy then either gets stored or immediately used to maintain speed. "

Welcome to the future....

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#10
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Re: Just Curious About Electric Cars

03/17/2012 9:57 PM

I love it when a plan works that smoothly.

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#12
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Re: Just Curious About Electric Cars

03/17/2012 11:16 PM

I'm just a cog in the machine of life....

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#14
In reply to #9

Re: Just Curious About Electric Cars

03/18/2012 11:58 AM

It all looks great.............................as long as you don't factor in the fuel that is burned to create the electricity to charge the car.

tcm is correct. As long as our focus is on saving the planet rather than hitting peak efficiency, we'll be mired in things that "sort of" work.

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#39
In reply to #9

Re: Just Curious About Electric Cars

03/19/2012 1:02 PM

The Volt is really still a concept car, but you can buy one if you have plenty of money. In addition to its low profile Mountain Mode, it has a very advanced system for cooling the batteries, engine, and occupants. ALthough not stated as such in the document I read, it seems to be a heat exchanger.

I am hoping the Volt technology makes it through to a next generation, and is priced close to the hybrids, such as the Prius.

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#61
In reply to #39

Re: Just Curious About Electric Cars

03/22/2012 9:51 AM

The Volt's are available now. (not a concept car)

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#13

Re: Just Curious About Electric Cars

03/18/2012 10:17 AM

Aerodynamic drag is a huge factor, also railroads were designed to minimize steep hills and sharp turns.

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#15

Re: Just Curious About Electric Cars

03/18/2012 10:26 PM

Together will all that has been said about steel wheels and rolling resistance, economy of scale, wind drag, level "roads". They also don't have to stop and start at every intersection - we do - for them!

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#16

Re: Just Curious About Electric Cars

03/18/2012 10:41 PM

There is nothing more efficient that a steel wheel rolling on a steel rail...well except perhaps maglev. Once moving, a single human can keep a boxcar rolling on flat ground. Railyard workers carry around a wheel jack used for overcoming the initial friction of wheel bearings, and once moving, they can roll the car down the track.

Rubber tires are made for comfort and are loaded with rolling resistance, even radials. This is why a tire inflated to rock hard will give better mileage, and under-inflated costs extra fuel.

Perhaps fuel is different, but you wouldn't see that by looking at the engine's exhaust...looks just like any other diesel exhaust.

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#17

Re: Just Curious About Electric Cars

03/19/2012 12:26 AM

I too was skeptical when I first heard this, so I asked an automotive expert mechanic, and parts designer about it. He informed me that the secrete to this amazing statistic, has a two fold answer:

Firstly, is the fact that the rail car wheels have so little friction to overcome especially compared to that of a rubber tire on asphalt, that the ratio is practically 1000% less of an impediment to the progress of the load. Secondly, the majority of the energy expenditure for moving such a gargantuine load is just getting up to speed. Maintaining the momentum to keep that massive load moving on flat ground is negligible in comparison to an automobile. All this is evidenced by the fact, that long trains may take as much as two to five miles to stop.

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#19

Re: Just Curious About Electric Cars

03/19/2012 1:13 AM

Here's a bit of information you may not have heard about...

http://www.youtube.com/watch?v=bEZsumCk9Sk

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#20
In reply to #19

Re: Just Curious About Electric Cars

03/19/2012 1:20 AM

Yeah, the car manufacturers all have this conspiracy and agree never to have good fuel economy - even if it sends them broke - please....

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#40
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Re: Just Curious About Electric Cars

03/19/2012 2:00 PM

I wouldn't say they are in a conspiracy per say but they (US auto makers) definitely have a 'our sh!t don't stink and doesn't need to change' attitude over fuel economy in far too many of their products.

I don't need to go into details but I know a vast number of people including many here and myself would testify that the fuel economy's of most of todays vehicles are less than or equal to many models that were around 30 - 40 years ago before emission compliance and what not and many of those vehicles were of equal or greater weight and engine power too.

Don't get us started on the foreign market vehicles that have been walking all over the US made stuff in economy, power, factory options, quality, price, for about as long either.

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#21

Re: Just Curious About Electric Cars

03/19/2012 2:16 AM

Hi Toolman,

It is very easy to push a 1 ton rail car, you could even push a ten or twenty ton rail car, but just try to push an F250 or a truck and trailer unit, it takes a lot more energy, and I just don't have it.

Hard rails, beat pneumatic tyres all the time mate.

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#22

Re: Just Curious About Electric Cars

03/19/2012 4:30 AM

Why not run a generator.
Isn't this almost the same as what we call, a 'hybrid' and it's already being done.
Del

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#33
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Re: Just Curious About Electric Cars

03/19/2012 12:01 PM

Doooode!

If I took my gas hog Dodge Ram pickup (12 mi/gal.) filled it up with M&Ms, drove it 12 miles, the cost to transport ONE m&m would be too small to measure...get the picture?

That train is using hundreds of gallons of diesel, and transporting hundreds of tons of goods.... Dude!

How far up a snake's a$$ can you see in the dark?

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#34
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Re: Just Curious About Electric Cars

03/19/2012 12:07 PM

That is known as economy of scale. Dude!

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#37
In reply to #33

Re: Just Curious About Electric Cars

03/19/2012 12:36 PM

Cat's have excellent night vision so, I expect Del could see pretty far up there.

I also expect he has a better grasp of the problem, and solutions, than you!

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#55
In reply to #33

Re: Just Curious About Electric Cars

03/21/2012 6:03 PM

I'll bite. How far?

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#79
In reply to #33

Re: Just Curious About Electric Cars

05/03/2014 12:33 PM

EXCEPT, that the CSX's ad specifically states that they are transporting a TON of freight 468 miles on a GALLON of fuel. Fill your car with M&M's which weigh a ton apiece, and even try moving your car, let alone go 12 miles. You are not using the right proportions in your flawed analogy Dude.

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#23

Re: Just Curious About Electric Cars

03/19/2012 4:54 AM

Hello everybody,

CSX is a Railroad company: so the explanation is simple:the rolling resistance on railroad tracks (between steel wheel and steel rail) is between 15 and 30 Newtons/ton of load, but on road (between rubber tyre and macadam or concrete) the rolling resistance is between 150 and 300 Newtons/ton on average. That means up to 10 times more!!! Thats all the benefits to use railroad for mass transportation...

It explains also the difference in fuel consumption between railroad and car to move 1 ton on 500 miles: 1 gallon for the train and 10 gallons for the car.

But the electric transmission of the power of the diesel or gasoline engine to the wheels cannot help the car reducing his fuel consumption: in the contrary: the system is too complicated and so too expansive and heavy for the limited power of a car. On the railroad, in the contrary, the electric transmission of the diesel engine to the wheels is needed because of the very high power (high torque also) thay must be transmitted to the wheels (6000 HP for a locomotive in comparison with 100 HP for a car). And we know that for the railroad the weight of the complete system is not a so important problem than on the road....

That's all the difference between rail and road transportation...

I hope I give you a first explanation...

With kind regards

Léon-Jean LAKAIE

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#24

Re: Just Curious About Electric Cars

03/19/2012 7:18 AM

Just go down to the rail yard and watch a fully loaded train start moving! The amount of energy expended (watch the smoke and listen to the noise) is quite large compared to rolling down the tracks when up to speed. (heck I'd like to go back to steam!)

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#25

Re: Just Curious About Electric Cars

03/19/2012 7:57 AM

Thanks all, I am familiar with the gas/electric hybrids and yes I do understand momentum and friction and that once the rail car is moving it tends to stay moving. It still seems to me that the world is focused more on the environment. If an engine is worse for the environment but burns much much less fuel then in the big picture it would be better for the environment. look up the ingocar and see what they are doing. I do not know what stage they are in yet but they use a small engine to presurize hydraulic fluid in an accumulator and then use that to run hydraulic motors in each wheel. It looks pretty straightforward. check it out at www.valentintechnologies.com

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#26

Re: Just Curious About Electric Cars

03/19/2012 7:58 AM

see Prius, Volt. It's commonly called a hybrid.

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#27
In reply to #26

Re: Just Curious About Electric Cars

03/19/2012 8:23 AM

PFR, If you had read my post, I am familiar with the hybrid which is not the overall issue I was referring to. For one, generating electricity to charge a battery is one thing, my issue is why not generate electricity to run motors directly, thereby eliminating losses due to charging. This also eliminates the transmission and other parts of the ICE and you are merely running the motors directly from the generator. There are tradeoffs in everything but my question since I am not an expert in electrical engineering that it seems to me it would be more efficient to run electric motors directly from the generator, than to charge batteries then run motors.

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#32
In reply to #27

Re: Just Curious About Electric Cars

03/19/2012 10:27 AM

You are confusing production with demand, which is why you must have a storage device to effectively (efficiently) use an engine/generator configuration. Demand curves are not linear (acceleration, braking, etc) but efficient production (generation) is.

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#47
In reply to #32

Re: Just Curious About Electric Cars

03/20/2012 8:02 AM

I agree. I own a 2011 Prius and have done quite a bit a research to understand how it works. First off there is not a mechanical linkage between the engine and the wheels. It is all electric. The ICE runs only to turn a motor/generator. In fact there are 2 motor/generator units. The larger one is used to move the car. The traction battery is used to operate the traction motor. If I understand it correctly the battery is also used as a boost for hard acceleration along with the ICE generator set-up. With all of this said I think it is a bit of smoke and mirrors as to how cost effective it is versus mileage. Sure in the summer I get around 54 mpg. My best has been 56.1 on a 2 hour trip that was filled with hills to climb and coast down. In the winter the car uses hot water for heat so the ICE runs to do that when the motor/generator is not really needed. So, the MPG dropped to around 45. I made up a simple ms excel spread sheet when we were car shopping. We were parking my 15 mpg Chevy Silverado 4x4 to save on gas. In comparison to it once we were looking at mpg ratings in the 30's the savings started to drop off dramatically. We could have purchased a year round 40 mpg car for far less money than the Prius. Along with that a much less complicated electrical system. With this said I saved around $4,000.00 in fuel over the past year. This is true savings as I did include the fuel expenses to run the car. In my case this is a free car. The money saved in fuel has more than covered the payments.

As a side note I have to mention how much I miss my truck. So much so that I have purchased a hicth and 4x6 trailer for the Prius. All said and done it is all free after fuel savings as well. Most of the trips we were making to the lumber yard and home stores are easily within the load limits of the little Prius. And the stores we goto are a 40 mile round trip = 1 gallon in the Prius vs 3 gallons in the truck.

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#48
In reply to #47

Re: Just Curious About Electric Cars

03/20/2012 8:22 AM

My post was already to long so I wanted to add this separately. I think you asked a good question. Sure there are some apple to oranges comparisons with rolling resistance, drag, and so on. But still a valid question. I have to think we are spoiled. The car companies get blasted every time. "Why did you take a mustang and turn it in to Shetland pony?" "Why would I buy this truck that can only pull this when that truck can pull that?" They will make what we demand. Living in a rural area I see kids and adults driving jacked up 4x4 trucks that rarely see a dirt road or pull a trailer. If we really want people to think mileage then we need MPG readouts in the dash with the rest of the gauges. There was an out cry for the third brake light several years ago and now it is on every car and truck. I drove a Dodge Ram with a manual tranny and had a blast trying to see how high I could get the MPG average to go. Same with the Prius. I have found in town I can spend more time coasting and not slow down the flow of traffic than I thought possible. Granted I do not live in a city where it is bumper to bumper.

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#49
In reply to #48

Re: Just Curious About Electric Cars

03/20/2012 8:52 AM

I know much is due to demand, which I think is why this country is a bit backward as far as mileage. I am not much on government regs but I think in this case they really need to press for better mileage. I am all for the environment, but if an engine uses 50 percent less fuel but is a bit worse for the environment then the tradeoff is visible, I am not sure we can have 100% environmentally friendly AND high mileage, at least at this point in time. I guess my point is that sometimes things can be way overengineered and it seems to be the thing these days, why buy a jaguar when a smart car will do, or why use a laser measuring device with accuracy to the thousandths when a simple tape measure will do. If we can run a simple system to run a vehicle that will get us from point A to B in reasonable time, then it seems to me a better option than, say, a tesla which costs an arm and a leg.

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#50
In reply to #49

Re: Just Curious About Electric Cars

03/20/2012 9:37 AM

I have found several things in life that are counter to what I thought would be logical. I have found with the Prius when I was driving slower and accelerating slowly my mileage was worse than just taking off and getting up to speed. Sure the initial burst was heck on the mileage at that point but I then spent more time maintaining speed and therefore the overall mileage was better. I also found I get about the same mileage at 65 on flat ground as I do at 55. There may be some small variation that a long road test will prove but for me it is close enough to call the same in this instance. My thought behind the MPG readout is to retrain our way of thinking about how we drive. I think environment and mileage can be one and the same. We just need people willing to go against the norm and try new things. As a Prius owner I get laughed at. Throw a trailer on it and you really turn heads. But at the end of the day my car gets better mileage than my motorcycle. (2004 HD Electraglide Classic 30-32mpg)

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#64
In reply to #49

Re: Just Curious About Electric Cars

03/22/2012 7:57 PM

Increased highway injuries and fatalities should be factored into the regulations. Many people complain there are no studies showing people die from 2nd hand smoke.There are numerous studies that show the increased casualties for every 100 lbs reduced.

In addition, substituting plastic for glass or steel adds maintenance and environmental issues that are not addressed. How many of you drive with fogged out plastic headlights? Ever price replacements.

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#65
In reply to #64

Re: Just Curious About Electric Cars

03/22/2012 10:10 PM

I just replaced the headlights on my 90 Ranger, I couldn't see a thing at night. Luckily, I got them wholesale through a friend. I see plenty of fogged plastic headlights, and I doubt the miracle polishes sold on tv work. A friend told me the headlights for his big pickup cost over a thousand dollars. I could not believe that!

I see older vehicles with the old round or rectangular glass headlights. They are very cheap, last a long time, and are easy to change. I guess that was just too good a thing for the car manufacturers, they just had to mess it up expensively. Get the car out of the showroom, and have these little bombs go off regularly to keep the service money coming in.

I refuse to purchase any vehicle with plastic headlights. I will shop for one with glass lights, even if I have to purchase an older vehicle.

I might have heard of aftermarket glass lights, will look in Google.

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#77
In reply to #49

Re: Just Curious About Electric Cars

03/30/2012 3:11 PM

I am not sure we can have 100% environmentally friendly AND high mileage, at least at this point in time.

In fact, despite what the conspiracy theorists say, engine efficiency has continually increased at the same time that emission controls have been implemented. In the last 30 years, peak efficiency of car engines has gone from 25% to 33% (or 37% in the case of the Prius). 30 years ago, general aviation aircraft engines were 25% efficient, and are still 25% efficient, because they do not make use of the precise combustion control techniques used in cars. If they were required to comply with car emissions standards their efficiency would be much higher.

In 1960, the VW Beetle advertised 25 mpg fuel as being a very good thing, and tests of early compacts like the Ford Falcon (by magazines like Popular Mechanics, Car and Driver, Motor Trend) showed numbers in the mid to high teens. Now huge, heavy sedans get better than 25 mpg. The Prius, which is twice the weight of an original Beetle, gets twice the MPG figure. Its engine is 50% more efficient than the 1200cc VW engine.

The conspiracy theorists are never able to supply BSFC charts for these mythical old engines that (they claim) are more efficient than modern engines. (BSFC -- Brake specific fuel consumption shows the amount of fuel burned per hp hour, or kWh).

Motorcycle engines, which are subject to much looser emission controls, are substantially less efficient than car engines on a BSFC basis. (In other words, when a Prius produces 20 HP it consumes 2/3 the fuel of a Honda CBR 600 motorcycle engine producing 20 HP.) Thus, the 400 lb Honda gets worse mileage than the 3500 lb Prius. (There are actually a lot of factors involved here.)

Honda is capable of making highly efficient motorcycle engines but they do not because they are not required to do so.

A BSFC of 220 grams per kilowatt hour is considered very good (for a gasoline engine) today. In the mid 70's a Kawasaki Z200 engine peaked at 335 g/kWh (250 g/hp-hr), and at half HP output (but still full throttle) was 400 g/kWh. (300g/hp-hr). At partial throttle, the numbers get even higher (i.e., worse). The Z200 was an economical commuter bike, built with fuel efficiency in mind. It had essentially no emission controls whatsoever. 400 g/hp-hr translates into dismal efficiency: 13.1 kWh/kg (gasoline) x .4 = 5.24 kWh input for 1 kWh output. 1/5.24 = 19% efficiency. Part throttle... even lower.

String together four of these z200 engines, and you'd have an engine of just under 80 hp -- about the same as a Prius engine. The Prius, when producing 35 HP, would consume about half the fuel of this old pre-emission-controls engine would at 35 HP.

(35 Hp is about the center of the 220 g/kWh island for the Prius.)

Bad old days (Kawasaki):

Modern (Prius):

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#56
In reply to #47

Re: Just Curious About Electric Cars

03/21/2012 6:17 PM

Unfortunately your research led you astray on the reality that the petrol motor in the Prius IS coupled to the drive train and the car really can't go above about 35mph without it running. Your comments are more true of the GM Volt - at least below 70mph and above 70mph with some caveats.

See this - try the simulation:

http://eahart.com/prius/psd/

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#57
In reply to #56

Re: Just Curious About Electric Cars

03/22/2012 7:14 AM

I just watched the video again and I missed that the first time I saw it.

http://www.youtube.com/watch?v=ZmHpSyTsfm0&feature=related

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#63
In reply to #47

Re: Just Curious About Electric Cars

03/22/2012 12:24 PM

This article states that the Prius engine CAN power the wheels independantly from the motor:

The power split device is the heart of the Toyota Prius. This is a clever gearbox that hooks the gasoline engine, generator and electric motor together. It allows the car to operate like a parallel hybrid -- the electric motor can power the car by itself, the gas engine can power the car by itself or they can power the car together. The power split device also allows the car to operate like a series hybrid -- the gasoline engine can operate independently of the vehicle speed, charging the batteries or providing power to the wheels as needed.

The VOLT, however, never uses the engine alone to drive the wheels, For greater horsepower, the engine can drive a generator, which drives a second motor to assist the main drive motor.

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#68
In reply to #63

Re: Just Curious About Electric Cars

03/23/2012 6:56 AM

I have to respectively disagree. The video that was posted in #47 explains how it works very nicely and states that the ICE is not connected to the Motor Gen #2 which is what drives the wheels. I'm willing to listen to any argument but please point me to something that show how the ICE is connected to the wheels at any time.

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#69
In reply to #68

Re: Just Curious About Electric Cars

03/23/2012 1:03 PM

Here is a site that explains the Prius drive train:

http://www.ecrostech.com/prius/original/PriusFrames.htm

One line specifically says (paraphrasing) "the ICE can be mechanically connected to the drive train through the PSD.

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#76
In reply to #69

Re: Just Curious About Electric Cars

03/24/2012 8:08 PM

Thanks...that's a much better explanation than the other video. So I stand corrected and better educated...the ICE does in fact power the wheels at times.

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#29

Re: Just Curious About Electric Cars

03/19/2012 10:03 AM

what they arent saying is that 1 locomotive engine (16 or 20 cylinder emd) is burning 2000 gals in a 24 hour period give or take. but nitrogen takes most of youre heat so maybe if you put a nitrogen scrubber on youre air intake this may take care of the problem. also thru electrolisis you can separate hydrogen and oxygen from water as a fuel. david klein from tampa fl made systems that do this. but he got bought or killed good luck finding him. heres a fun fact emd engines are 2 stroke. yeah no sh#t. good luck Arturus

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#44

Re: Just Curious About Electric Cars

03/19/2012 4:22 PM

At what average speed? I wouldn't be satisfied driving across the country at 35 mph, although freight doesn't care.

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#45
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Re: Just Curious About Electric Cars

03/19/2012 4:42 PM

Grain trains are restricted to 45 MPH due to their weight and related wear and tear on tracks but high priority freight units tend to push 70+ MPH track speeds and Amtrak "unofficially"gets into the 80 - 90 MPH levels fairly often.

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#51
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Re: Just Curious About Electric Cars

03/20/2012 2:16 PM

officially 89 mph speed limit for Amtrak 30 years ago, when the bed would support it. and the steel to steel is correct, that's why they have to use sanders on all wheels to stop

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#46

Re: Just Curious About Electric Cars

03/19/2012 7:37 PM

Besides all the good information here about rolling resistance and aerodynamics plus economies of scale it could still be advantageous to do what you propose from the point of view that the average car engine puts out about 250 hp but only 200 gets to the rear wheels. But when the car is cruising down the freeway that engine is just barely ticking over at 1800-2000 rpm and the engine is only putting out about 100 hp. An electric motor has its torque from 0 rpm and to maintain a car at highway speeds does not require much more than 50 hp. So a 125 hp gas engine can power a generator which will put out 100 hp which will run an electric motor at 80 hp so there could be a net savings in fuel costs.

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#52

Re: Just Curious About Electric Cars

03/21/2012 7:40 AM

I got to thinking last night and remembered there is a diesel motorcycle the military is using that gets great mileage. I found it on the net this morning and am including the link. It gets around 110mpg while making 28hp. While this is a little off topic in the sense it is not addressing the generator only vs generator and batteries, it does address the environmental and economy working together issue that has been brought up.

Here is an excerpt from the article: "Although the motorcycle is about 20-30% more expensive than a comparative conventional motorcycle, there would be cost savings for riders and environmental benefits in that the diesel motorcycle can do 110 miles per gallon - a little over twice the range of a conventional motorcycle," said Fred.

Found on GIZMAG

http://www.gizmag.com/go/4272/

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#53
In reply to #52

Re: Just Curious About Electric Cars

03/21/2012 8:05 AM

This is pretty cool too. As the article mentions though, the EPA does a pretty good job at hobbling exploration into alternative fuels. If the government wants the true innovators to innovate, they need to get off their backs and let them get to work.

The cylinders in the video look safe to me.

http://thekneeslider.com/archives/2011/04/11/natural-gas-conversions-for-motorcycles-would-you-buy-one/

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#54
In reply to #53

Re: Just Curious About Electric Cars

03/21/2012 9:22 AM

Do think that we don't have CNG cars because the government is on the back of innovators? The link you provided does mention the problem with tank safety, is that what you are referring to? I'm always curious about the regulation restraint, and I would write my Congressman to ask for help if I could identify one.

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#59
In reply to #54

Re: Just Curious About Electric Cars

03/22/2012 8:30 AM

I was referring to this:

The EPA makes you jump through all sorts of hoops to do a conversion, the kit has to be approved, the tech doing the work has to be certified, but even with all of that, what if one of the motorcycle companies built kits for recent engines and received the proper certification then trained their techs to install the retrofits, there's a whole new market where they might find demand even in a down economy, you know, going a little outside the box instead of calling new graphics and paint a new model.

And this:

Cylinder safety, something many are concerned about, is far less of a problem than commonly believed.

My point was.................that we need to eliminate most of the bureaucratic hoops if we truly want to make progress.

It didn't take much reading to know that I won't be attempting any conversions any time soon. Conversions are relatively easy, getting through the bureaucratic maze is not worth the time and effort, for most.

http://www.epa.gov/otaq/consumer/fuels/altfuels/altfuels.htm

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#58

Re: Just Curious About Electric Cars

03/22/2012 8:05 AM

...but the ICE only "assists" and never actually drives the wheels as it's NOT CONNECTED to motor generator 2, which does DRIVE the wheels.

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#62

Re: Just Curious About Electric Cars

03/22/2012 10:44 AM

Back in the mid 90's there was a lot of research done on getting cleaner burning diesel for highway trucks. They developed a much cleaner fuel but low and behold they had to burn twice as much to cover the same distance. Now we get the story that plug in cars are the cleaner way to go. Here is in interesting paper on the subject.

http://motivepower.wordpress.com/blowing-the-lid-off-the-235-mpg-electric-vehicle-hoax-or-when-is-a-gallon-not-a-gallon/

Running a fixed load fuel engine to power a generator and then store excess may be the best way in the future but just going off and making one type of system and expecting it to be the panacia is shortsighted. It will require several types of systems depending on the availble (local) fuels so a massive new infrastructure is not needed and the decades it takes to establish. The key is whatever method or system is developed , must be able to overcome the billions of manhours and development costs that has gone into the present ICE system.

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#70

Re: Just Curious About Electric Cars

03/24/2012 11:52 AM

a diesel/electric locomotive engine is designed for optimum efficiency within the small parameters needed to pull freight. a car engine is designed to operate over wider parameters that's needed for highway driving resulting in a give or take situation.

unfortunely, the train rails where scrapped decades ago when the low price of fuel made trucking a better alternative.

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#72
In reply to #70

Re: Just Curious About Electric Cars

03/24/2012 3:17 PM

Actually unions did as much damage to the small town rail industry as anything else. Running the trains is cheap paying the people who run them is not.

The private owned freight truck runs at a as low of profit as the owner can handle while the unions run at as low of work load and high of pay as they can get a way with.

Where I work and with what I do relating to fueling trains is a one person job for non union labor such as myself however if done by union rules there would be 3 - 5 people required to do my job and each one making what I make or more an hour and I am paid well for what little I actually do in a typical day.

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#73
In reply to #72

Re: Just Curious About Electric Cars

03/24/2012 3:29 PM

I've mentioned this before on here. I never would have believed it.

I was working on a union construction job one time, getting paid prevailing wage as a non union worker. I had to paint a bathroom that had no light in it, so I ran an extension cord and a drop light. I didn't even know it was against the rules.

Long story short................the light got unhooked, and I sat on my butt for almost 2 days and waited for a union electrician to run a light for me. It was disgusting.............................I would actually prefer to work, over sitting and doing nothing.

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#74
In reply to #72

Re: Just Curious About Electric Cars

03/24/2012 3:32 PM

Why has unions become such a pariah? Like all things in life there are good unions and bad unions. A union gave us the forty hour work week instead of the seventy hour work week. A union made employers liable for on the job injuries instead of dumping a wage slave off the roster like some damaged raw materials. As I started there are unions rules and operations that make no sense today (bad unions) but they are not all bad.

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#75
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Re: Just Curious About Electric Cars

03/24/2012 6:13 PM

I never said all unions are bad however given the history of what they first represented over what they now largely represent and show themselves to be is two vastly different things.

In the beginning they represented the power of numbers to make things better as a whole for everyone but now much of that power has largely been corrupted and twisted to what ever legal limits it can get a way with to protect the greedy and dishonest over the people that it was truly intended to work for.

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#71

Re: Just Curious About Electric Cars

03/24/2012 2:12 PM

Something I just wanted to throw in here, was the fact that our auto's, in addition to producing direct locomotion, also are busy producing a fair amount of electricity. Not to mention some hydraulics.

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#78

Re: Just Curious About Electric Cars

03/30/2012 4:46 PM

In either hydraulic or electric series hybrids, there must be a storage system to compensate for the losses in the system. Otherwise, the system is less efficient than mechanical transmission. Mechanical transmissions are about 95% efficient from engine to differential. Electric motors and generators are about 90% efficient, so together are 81% efficient. Hydraulics are about the same.

(Hydrostatic transmissions are used only when their infinite speed variability can outweigh the cost and losses. Even small units like on a Cub Cadet have cooling fans -- an indication of losses going out as heat. )

In a series hybrid like the Volt (or like my Zing) the losses of converting from mechanical power from the engine to electric power and back to mechanical are compensated by having the engine only run when highly loaded, where its efficiency can be 3 times as high as when it is running with a light load. (This poor efficiency at light load is why a Lamborghini gets such awful mileage: when you are operating a 2% of maximum power a lot of the time, efficiency is terrible.) Hydraulic hybrids, like the UPS trucks, also try to run the engine only at high load, and must store energy to allow that to happen.

Without a storage device, you cannot operate the engine at high load. (If you only need 10 hp to travel along at 40 mph, you cannot operate the engine at 100 hp, unless you have something to absorb the excess energy.)

Both hydraulic and electric hybrids store braking energy, (in addition to allowing the engine to run at high load). They are about equally efficient in that respect.

To travel efficiently at 40 mph, a typical car might need a 10 hp engine. The problem with installing a 10 hp engine is that you can't go up hills or drive faster than 40 mph. So hybrids are a compromise, with stored energy making up for a small, efficient engine.

On the Zing, the HP required for acceptable performance (hill climbing, acceleration, top speed) is 40. But cruising at 60 only requires 6 HP, at which level a 40 hp engine would be very inefficient. So instead, a small engine runs periodically at full load, to keep batteries charged. The electric motor can then supply bursts of 40 hp as required. The efficiency gain from running only at full load far more than compensates for the losses of going from mechanical to electric and back.

Where this falls apart somewhat is at constant cruise on a level road. Then, with the engine driving a generator and the generator feeding a motor, you are incurring conversion losses you would not have with a shaft from engine to differential. In my case, it doesn't matter: 115 mpg vs 100 mpg makes little difference -- either way you use very little fuel (and most of the time you run on electricity from the grid, which is about 1/5 the cost of running on gasoline). But for the Volt, their mpg number was embarrassingly low, compared to the Prius, so to them, 15% was worth the additional complexity of implementing direct mechanical drive to the wheels. Even so, they still fell well short of the Prius, and have an incredibly complicated, expensive, system.

Trains run on tracks and have an incredibly small frontal area relative to the load carried. They don't stop for stop lights or traffic. Whether the train is straight diesel or diesel electric is somewhat secondary.

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