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To: KingOfVagabonds
It turns out that's not correct. We're now told by Volt's engineering team that when the Volt's lithium-ion battery pack runs down and at speeds near or above 70 mph the Volt's gasoline engine will directly drive the front wheels along with the electric motors.

I'd love to see the schematic of the drivetrain to see how they accomplished this.

In the Prius, the electric motor is directly engaged to the driveshaft, thus providing a one-to-one correlation between the electric motor speed and the car's speed. But they use a ring/sun gear system to attach the gas engine shaft to the same driveshaft (with a 2nd electric motor providing a variable-ratio connection using the sun gears), so that the gas engine can provide additional power to the driveshaft without regard to the speed of the driveshaft and gas engine.

Now, I'm not surprised the Volt puts the gas engine onto the drivetrain. Once you have a gas engine running, it's more efficient to connect it directly to the driveshaft than it is to use it to run a generator, store the power, and retrieve it. That's why the Prius does this -- it's the naturally best engineering solution once you put a gas engine in an electric car.

As to the rest, I'm not sure how much of a "lie" there is -- the "230 mpg" number was based on taking some short trip in which most of the trip would be by electric and which therefore would take "0" gallons of fuel (because the EPA has no way of measuring the gas-equivalent cost of electricity used to charge the battery).

Nobody who knew anything about the science would have thought the car could get 230 mpg while running the gas engine. The Prius is a highly advanced car with meticulous workmanship in this area, and can't do much better than 50 mpg. The Volt, being a larger car with more weight in batteries, wasn't going to do as well.

So the whole 230 mpg thing was hype to begin with. If you drive 50 miles, and 40 are on battery, and the last 10 get you 40 mpg, you will have used .25 gallons to go 50 miles, which is 200 mpg.

People have acheived these numbers in a Prius by modifying the car to add a second set of batteries and a charging unit, to extend the electric range and provide grid-electric replacement for some of the gasoline used. But I've not seen a full power utilization report so we could tell if it is more efficient to use electricity instead of gasoline in this instance.

11 posted on 10/11/2010 11:28:22 AM PDT by CharlesWayneCT
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To: CharlesWayneCT

Good insight, thanks for contributing that. I don’t know much about the mechanics, all I know is this gubmint turd has been shrouded in lies and half-truths since its inception. If Toyota had done this, they’d be hauled in front of congress to embarrass them and increase GM’s market share.


16 posted on 10/11/2010 11:35:26 AM PDT by KingOfVagabonds
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To: CharlesWayneCT

Can’t we just get one of those battery chargers that plugs into a cigarette lighter, and use it to charge up the VOLT’s (or any other electric cars) batteries?

You’d never have to stop for anything.

; )


22 posted on 10/11/2010 11:47:10 AM PDT by UCANSEE2 (lame and ill-informed post)
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To: CharlesWayneCT
So the whole 230 mpg thing was hype to begin with. If you drive 50 miles, and 40 are on battery, and the last 10 get you 40 mpg, you will have used .25 gallons to go 50 miles, which is 200 mpg.

of gasoline...

Of course once you factor in the energy required to recharge 40 miles of driving back into the battery, the equivalent total energy consumption doesn't look quite so rosy.

(unless of course you only recharge using solar panels, wind, or ? 8^)

25 posted on 10/11/2010 11:57:11 AM PDT by jonno (Having an opinion is not the same as having the answer...)
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To: CharlesWayneCT; All
IMO, it's not really about whether the Volt is a good car, or what the "real" MPG number is...

It's about the inflated fleet milages that the gov't is mandating. Figure that for every 230mpg Volt Chevy sells, they can produce 12 gas-guzling pickups that people actually want to buy, and maintain the required fleet mpg numbers.

So, the Volt is just a means to an end. It only needs to be marketed well enough to fool a few dumb eco-nuts, and dumber politicians.

Myu opinion only. Your mileage may vary. :-)

32 posted on 10/11/2010 12:24:11 PM PDT by wbill
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