News: GM Lied: Chevy Volt is Not a True EV

Spectre said:
not using a second electric motor as a generator.
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There are two electric motors, one is used as a generator in charge mode.

In addition, an electric motor can be a generator or a motor, but it cannot do both tasks at the same time. Basic physics limitation, so your explanation as quoted below makes zero sense.
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A little clarification then: The second motor is connected to both the ICE and the wheels when in charging fast-driving mode. It gets all its energy from the ICE. Some of that energy is put into the batteries/first motor, acting as a generator. Some of that energy is used to drive the wheels, acting as a motor.

Finally, I strongly doubt that the range is really 40 miles on electric drive alone 'at any speed' considering that the engine couples to the wheels at (claimed) speeds over 70mph, and electric range drops radically as speeds increase.
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The ICE will only couple to the wheels at high speed with empty batteries. It will not couple to the wheels at high speed while discharging.
Obviously the range drops with very high speed, as you say yourself "basic physics". Popular mechanics tested highway driving at 78mph if I recall correctly, and got 33 miles.
 
argatoga said:
GM should have made the car less fuel efficient, so they could make a pointless distinction between it and the Prius.
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According to Car and Driver, they've got you covered on that.

Either way, one thing?s for sure: Operating an EV can be exceptionally cheap. Assuming 35 miles of electric range for the Volt yields a cost per mile of just 4.6 cents. That?s almost 40 percent less than that of a Volkswagen Golf TDI diesel getting 40 mpg and 24 percent cheaper than a Prius getting 45 mpg.

The economic picture is dimmer when operating the Volt using its gas engine. We averaged 35 mpg for our gas-powered miles and saw 33?34 mpg at a steady, near-80-mph cruise?not exactly spectacular compared with today?s hybrids. Then again, no one should buy a Volt if they plan to run it extensively in extended-range mode.
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If you're going to mostly drive high-speed long-distance, buy a diesel. Nothing new that hybrids don't do that as well as the oil burners.

Hell, my conventional petrol estate can match or even beat 33mpg at near-80-mph.
 
:no: not a diesel hybrid, for long-distance constant-high-speed driving the hybrid part is useless.
A BlueMotion Golf will do high-enough mpg. Improving that will not lead to significantly less use of oil. Improving thirsty vehicles will lead to much greater savings.
 
As Narf said a hybrid isn't a good option if you plan on doing a lot of highway driving. The extra weight will be a detriment.
 
Extra weight, meh - my biggest quibble with the idea of hybrid long distance driving is buying expensive kit without using it. Take plug-in technology, if your car can do 50km at highway speed on the batteries alone then that's great for short commutes because it will take away most of the petrol/diesel consumption. If however your daily drive is a couple hundred km then you will have paid a lot of money for an empty battery. I know mentioning the environment is not always regarded highly here :lol: but you will all agree that the impact of making a car battery that is barely used is quite pointless.



If you're going to make vehicles use less oil, don't waste zillions on improving already-efficient designs. What's better, improving a 60mpg diesel to 200mpg (yeah, right) or improving a 15mpg guzzler to 18mpg?

60mpg -> 200mpg saves 0.012 gallons per mile, 15mpg -> 18mpg saves 0.011 gallons per mile - essentially the same savings.
 
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I fail to see the problem. The system is a pure EV/series hybrid until you run out of juice, at which point instead of just going "Well, shit, no driving at speed for you," the car switches to a hybrid system so you can, you know, keep driving instead of having to pull over on the New Jersey Turnpike. Where's the problem here? I think that's a goddamn fantastic idea.
 
GM's official response:

By Phil Colley, Chevrolet Volt Communications

We've officially started the media launch program for the Chevrolet Volt, and while it is generating strong critical acclaim because of its unique engineering, we want to clear up any confusion as to how the Voltec electric drive unit works among those who have not participated in the program.

The engineering of the Voltec electric drive unit is very sophisticated and as part of the media launch, we're diving even deeper into how the system works than we have in the past. We did not share all the details on how the system works until now because the information was competitive as we awaited patent approvals. Based on a small number of inaccurate media reports, we want to set the record straight.

Here are the facts:

- The Volt has an innovative electric drive system which can deliver power in both pure electric and extended range driving. The Voltec Electric Drive cannot operate without power from the electric motors. If the traction motor is disabled, the range-extending internal combustion engine cannot drive the vehicle by itself.

- There is no direct mechanical connection (fixed gear ratio) between the Volt's extended-range 1.4L engine and the drive wheels. In extended-range driving, the engine generates power that is fed through the drive unit and is balanced by the generator and traction motor. The resulting power flow provides a 10 to 15 percent improvement in highway fuel economy.

Our overriding objective in developing the Voltec Electric Drive was to deliver the most efficient, yet fun-to-drive experience in both pure electric and extended-range driving. We think our unique technology lives up to its most important promise: delivering our customers with the only EV that can be their primary vehicle, with EV operation for normal daily driving, and extended range driving for weekends, holidays, longer trips, all with no range anxiety.

To read a few perspectives on the technology, please click the links below:

Motor Trend - Unbolting the Chevy Volt to See How it Ticks

"On paper, the Voltec drivetrain has more in common with a Prius (and other Toyota, Ford, or Nissan Altima hybrids) than anyone suspected. Each system employs a single planetary gear set, a gasoline-powered piston engine, and two electric motor/generators. But the way Chevy connects them is entirely different, and--if you ask me--superior."

Automobile Magazine - Chevy Volt Surprise

"To trump both the Prius and the Leaf, Volt combines their merits in one handy advanced-technology sedan. It employs cheaper and cleaner electrical energy drawn from the grid. It provides efficient electric drive without the usual compromises. It uses gasoline intelligently in a supporting role. It is a pure electric, a series hybrid, and a parallel hybrid all rolled into one."

The Car Connection - How GM Didn't 'Lie' About The Volt, And Why The Press Is Wrong

"Does that mean it's not an all-electric car the rest of the time? No. It just means that in addition to being an all-electric car, it has some hybrid-like capabilities. So Chevy delivers an EV with 340 miles range and adds in a power boost to maintain highway speeds even when the battery is discharged...and the media complains about it? This does not compute."

I hope this clears up any confusion and be sure to keep following along with our activities right here on Voltage, on Facebook and on Twitter.
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BerserkerCatSplat said:
I fail to see the problem. The system is a pure EV/series hybrid until you run out of juice, at which point instead of just going "Well, shit, no driving at speed for you," the car switches to a hybrid system so you can, you know, keep driving instead of having to pull over on the New Jersey Turnpike. Where's the problem here? I think that's a goddamn fantastic idea.
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Damn right!
Saying it is "just a Prius clone" is a little silly. It has it?s merits. If it?s a good product, GM is crap etc etc etc etc, it?s another discussion entirely.
 
I think this Exhaust Notes blog adequately sums up what I've been trying to say.

Partial Quote:
Eco-friendly transportation is big business these days, and with the electric vehicle universally considered to be the Next Big Thing in the evolution to greener pastures, automakers are hard at work trying to hasten the transition from hybrid to EV. The Chevrolet Volt, General Motors' much-hyped battery-powered wonder car, has long been touted by its manufacturer as the poster child for this tranformation.



The Volt, GM has claimed, uses an electric motor to drive its front wheels, with a gasoline engine present only to generate electricity. The Detroit automaker's cry has been long and loud: The Volt is an electric car, plain and simple.



Only it turns out that's not the case. As part of the Volt's recent media launch, GM revealed that its pride and joy does use its engine -- through a direct mechanical connection -- to assist in providing forward motion. The Volt, then, isn't quite an electric car. What gives?
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Sound like it is an electric car... right up until the juice runs out and you're about to be stranded, then it becomes a hybrid. Do I get a cookie?
 
TomCat said:
Sound like it is an electric car... right up until the juice runs out and you're about to be stranded, then it becomes a hybrid. Do I get a cookie?
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No, actually. Because it uses it for high speed driving as well. I guess you get half of a cookie for being half right.
 
Mr. Nice said:
No, actually. Because it uses it for high speed driving as well. I guess you get half of a cookie for being half right.
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Only at 70+mph, which considering the number of roads with speed limits over 70mph, I don't think it's that big a deal. I suppose GM could have limited it's speed to 70mph to keep it more EVish, but that would reduce the use-ability of the car. Those bastards. :p
 
TomCat said:
Only at 70+mph, which considering the number of roads with speed limits over 70mph, I don't think it's that big a deal. I suppose GM could have limited it's speed to 70mph to keep it more EVish, but that would reduce the use-ability of the car. Those bastards. :p
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As far as legal speed limits go, one would have to agree with your thinking. When was the last time you drove somewhere that you didn't go faster than 70mph? I'm not saying I ever go over the speed limit, just that I've noticed a lot of people do. :D
 
Mr. Nice said:
As far as legal speed limits go, one would have to agree with your thinking. When was the last time you drove somewhere that you didn't go faster than 70mph? I'm not saying I ever go over the speed limit, just that I've noticed a lot of people do. :D
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And if you are one of those people, you could still do so in the Volt. :p

It's kind of funny, but I notice quite a few hybrid drivers around here drive pretty damn fast. For hybrids, anyway. Which makes me wonder why they didn't just get a normal car and drive it normally. Instead they buy a hybrid and drive like crazy. Doesn't that defeat the purpose?
 
Yes, it really does. I once owned a Honda Civic, and when it was new I could get 45mpg on the highway, at a little over 70mph, around 3500rpm (seemed to be its most efficient spot). I would get passed by Prius' (Prii?) all the time, and I could only think they were probably getting around the same or slightly worse mileage than me.

Edit: The Prius cost about $10,000 more than a Civic at that time (2003), so even if they were getting in the upper 30's lower 40's, the added expense of the car negated any savings they had.
 
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