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OK, you've probably seen this thing about the Chevy Volt doing 200 MPG. Is this really possible with a relatively conventional steel car body, rubber tires, gas engine? Or is it some devious marketing hype?

I know how to make a 200 MPG car. You're talking bicycle tires (3 maximum) a tube frame and plastic body made basically out of thin sheet, no air cond, one or MAYBE two passengers in tandem seating, empty vehicle weight about 250 Lbs, keep speed below 40 MPH or so. Really not too difficult. With that, you could make a decent electric or series hybrid, too.

But, to meet federal safety standards, with conventional auto construction techniques (think sheet steel, stamped and welded together), 4 big balloon tires, seats 5 in palatial comfort, I just don't see how they can do this. And, especially with the typical lead-footed American driver, it seems like they are going to make a LOT of people REALLY mad.

So, what the HECK is up? Thanks in advance for any "Insight" (pun intended) on this.

Jon

It's a Chevy! If it does half of what they claim with in the realm of Joe 6 pack it will be a winner!

While I have caught heat over the years for slamming GM. and I would purchase a new Corvette or CTS-V over Volt. One thing GM knows about is hybrids, less the battery. One has to look no farther than there old Locomotive and Marine works. All that is missing over all is the battery. GM has the ablity to raise the bar to levels nobody has ever seen.

Question is???? Is Volt the start of that higher level or will it just be another main stream hunk of junk? Volt has top come out of the gate being able to meet all the insane claims and set the world on there keister. Or it's all for not.

Jon, the first generation Insight (with MT) is capable of 200mpg at low speeds. I did it over a 6mi round trip near Larry's house in Elkhart. Wayne managed a solid 220mpg in my car over a longer round trip later. No battery power was used to achieve these numbers. 200mpg was achieved more than once with two occupants (my trip was one and Laurie hit 212mpg with a passenger as well IIRC).

As for the Volt, the vehicle is not capable of that number using just the gas generator. The numbers GM has been crowing about are achieved by using the full AER (all electric range) and then a short distance on the generator… without taking the electricity energy equivalence into account.

As an example to illustrate this, imagine if you will that a fully charged Volt is driven 51mi. If we assume an average FE of 50mpg when in range extended (or "Charge Sustaining" in GM parliance) mode, you'll get 40mi of no gas plus 11mi using 0.22g to complete the trip. 51mi/0.22g = 231.8mpg

It should be obvious that this is somewhat disingenuous. If you drive a shorter distance that still requires the generator, you'll get higher mileage. Longer distances will result in lower mileage. If you take a road trip, the average will approach the efficiency of the generator (50mpg in our example above).

Using this same method, we already have a member (Jay — TheForce) who has achieved 299mpg over an entire tank. He's actually done the energy equivalence calculations and that number is far lower.

So, to answer your question, no not really. You have to pretend the electricity is magically insignificant in the calculation to make it work and even then, you have to restrict the distance traveled on the range extender.

C).

As for the Volt, the vehicle is not capable of that number using just the gas generator. The numbers GM has been crowing about are achieved by using the full AER (all electric range) and then a short distance on the generator… without taking the electricity energy equivalence into account.


Yup, after reading all the interviews with the GM guys, I came to the same conclusion, and worked out very similar numbers to yours. I think it will get about 50 MPG in the "extended range" mode, such as on long highway trips. Well, that isn't so terrible, but people who expect 230 MPG are going to be FURIOUS!

And, claiming 230 MPG while not mentioning the electric input to charge the batteries is essentially a FRAUD, and the EPA is apparently complicit in creating the mileage rules to permit them to publish this "rating".

Now that I know how the fraud works, I'll just be happily driving my HCH-II. I hope I don't see too many Volts on the back of tow trucks next year. I know the Prius and the HCH-II are mature technologies, who KNOWS how reliable or unreliable the Volt will be. Also, if the HCH-II's complete IMA system blows out, the car is supposed to still be drivable. For the most part, the Prius isn't, as their motor/gen system is also the transmission. Clearly, the Volt will be the same, if the inverter or battery pack suffers a major failure, the car is dead.

Jon

Like everyone said, the energy from the grid probably was not factored in.

Will the "New GM" realize marketing like the "old GM" is going to make them the "dead GM?" ;)