2011 Chevrolet Volt: Our A-Z Guide to the Volt as We Know It Today
By John O'Dell November 24, 2009
Pawing through the roughly 247.3 gazillion articles that have been written about the Chevrolet Volt to date - it is possibly the most written-about-in-advance new car ever - we've noticed one shortcoming: There's so much it's hard to find one place to go to get simple Volt specs and data.
Well, we're going to fix that, right now.
Here, in one easy-to-find, easy-to read place, is Green Car Advisor's compendium of what we know, surmise and can dig up in dark places about the Volt.
GM's been pretty open about broad details, more close-mounted about minutiae, so some things you'd think would be here - exact tire size, cabin space and fuel tank capacity, for instance - haven't been publicly announced yet.
We'll be adding to this little dictionary of Voltage as additional info becomes available, so check back frequently.
What Is It?
General Motors wants everyone to call it an extended-range electric vehicle, or E-REV, but to be accurate the 2011 Chevrolet Volt is a series plug-in hybrid. We expect that E-REV will become the popular designation, however, as it is short and snappy.
How does it go?
The Volt is an electric car in that its wheels are always driven by an electric motor. It is not a purely electric car, however, because it also carries a gasoline engine that serves as a generator.
The car's rechargeable battery pack (thus the "plug-in") holds sufficient juice to power the motor for up to 40 miles at low-speed driving, less at speeds above 20 mile an hour.
The engine-generator automatically kicks in when the battery charge is 70 percent depleted, providing the juice the electric drive system needs to keep operating.
Battery vs Generator
If never driven very fast or very far, and recharged every night, the Volt could operate as a pure-electric almost all of the time. The engine-generator would automatically start up once a month just to circulate lubricants, keep internal parts limber and let the electronics run an engine check to make sure everything is copacetic.
But if a trip lasts longer than the battery charge, or if the battery isn't recharged and runs down after a few trips, the engine-generator will come on, burning gasoline while producing electrical power that flows directly to the electric motor .
Contrary to what you might have heard elsewhere, the Volt's engine-generator doesn't recharge the battery pack. It can trickle a little excess juice into the pack from time to time, but its primary job is to keep the electric motor fed.
Engineers and technicians install battery pack in pre-production Volt.
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Fuel Economy
GM got a lot of headlines this summer by claiming that under one proposed federal test protocol, the Volt could qualify for a city-driving fuel economy rating of 230 miles per gallon and a combined range of around 100 mpg.
Don't count on it.
Some few drivers - those with short commutes on city streets who never, ever, take the Volt past the battery pack's daily capacity - could get something like that, but on the real world, mileage would vary wildly depending on driving styles and distances.
Any Volt fuel economy rating is a national average that depends on a lot of assumptions, and in the end few real people fit so well into every category that their driving meshes exactly with the scenarios used to come up with the rating (EPA fuel economy window stickers have proven that year after year after year.)
The feds haven't finalized a methodology for computing mileage in mixed fuel vehicles such as the gas-electric Volt, but there are gasoline-gallon equivalent formulas that can be applied to various types of energy.
Using the assumptions that a Volt would be driven an average of 1,250 miles a month, running in all-electric mode 62 percent of those miles and burning fuel in the engine-generator for 38 percent of the travel, Edmunds testing director Dan Edmunds (no relation) has come up with an estimated combned city-highway fuel-use equivalent of "less than 90 miles per gallon."
(He's still refining his numbers and promises a full article explaining all - we'll link to it - by early next week.)
It's the corporate opinion here, however, that MPG is no longer the best way to measure fuel economy. Some cars - the upcoming all-electric Nissan Leaf, for instance - will never use gasoline or any other liquid fuel - while others, like the Volt, will use electric power from the grid and fuel from the pump in varying blends.
We think an average monthly fuel cost, or MFC, is a better way than the now-outmoded MPG to enable consumers to compare fuel economy across the spectrum - a Volt, a Prius, an all-electric Mini E and a Honda Civic, for instance.
Using that methodology, we rate the Volt at an average of $54 a month versus $49 for the '09 Mini E, $67 for a 2010 Toyota Prius and $115 for a 2010 Honda Civic). You can compare those to other vehicles by perusing our exhaustive list of 2009 and 2010 model year MFCs.
Estimated Cost
$40,000
Tax Credits
- Federal: $7,500
- State and Local: Vary, but can be substantial. Austin, Texas, is talking about a $4,000 regional subsidy, for instance.
Passenger Capacity and Vehicle Type
The Volt is a four-seat, five-door, front-wheel drive sedan.
Performance
Top speed electronically limited to100 mph.
Fuel Capacity
Undisclosed. Thought to be between 8 and 10 gallons, regular unleaded.
Range
GM estimates total range on one battery charge and one tank of gas to approximately 300 miles, including 40 miles on the battery's grid-charge.
Battery
- Type: T-shaped, lithium-ion battery pack built by GM using lithium manganese chemistry cells from LG Chem.
- Weight: 180 kilograms, 396 pounds.
- Energy: 16 kilowatt-hours maximum energy capacity, 8 kwh usable energy.
Charging- 120 or 240 volts.
- Approximately 8 hours on 120-volt circuit, 3 hours on 240 volts. Not designed for rapid charging at high amperage.
- Will come with either 120-volt portable or 240-volt wall-mounted charger (left). GM hasn't decided which.
- Both will use the new SAE-J1772 specification universal North American charge plug.
3-phase AC, 150 horsepower (111 kilowatts); 370 lb.-ft. of torque (273 Newton meters).
Engine-generator
1.4-liter, four cylinder, flex-fuel (gasoline and E85 ethanol-gas blend), 71 horsepower (53 kilowatt) engine serves as the on-board generator and operates in a range of 1,400 to 4,000 rpm.
Transmission
- None in the traditional sense. The Volt uses a single-speed reduction gear to channel the 15,000 rpm electric motor's torque to the front wheels.
- Putting the "gear selector" into reverse merely reverses the polarity and spin of the motor.
- There's also a "low" setting that cranks in extra regenerative braking to capture more energy from the wheels when extra boost is needed.
- Unit-body steel construction with battery safety cage an integral part of the chassis.
- Four-wheel disc brakes with full regenerative braking system to use braking energy to generate electricity. McPherson struts front, compound crank twist axle rear.
Undisclosed but variously estimated at between 3,400 and 3,800 pounds. Vehicle Engineer Andrew Farah said last week that is "still heavier than we'd like."
Tires and Wheels
Goodyear Assurance Fuel Max low-rolling resistance tires, mounted on 17-inch forged aluminum wheels.
Dimensions (inches/mm)
- Wheelbase, 105.7 / 2685
- Length, 177 / 4404
- Width, 70.8 / 1798
- Height, 56.3 / 1430
- Cargo volume, 10.6 cubic feet / 301 liters.
LEAVE A COMMENT
Click here to comment on this entry.OK - Frank Weber explained the 1.4L generator to the media in Chicago last year. But it's a 74 hp (~ 50 Kw) modified- Atkinson cycle engine. Just how well will this car perform running on the generator only - when the battery pack is below minimum reserves?
I would like to take a Volt trip from Denver, west on I-70, north on US-40, over the Berthoud Pass, up to the west entrance of Rocky Moutain National park, across the park on Trail Ridge Road, and then from Estes Park back to Denver via CO-7.
I have yet to hear how well this car will perform in extended-range mode.
Thank you for the write up, but I have some questions.
First, why do you think it won't make the 40 miles even driving it at highway speed? Do you have any proof that driving at normal highway speeds, up to say 75 mph, the car can not go 40 miles on battery power? Have you tested this yet?
Second, what criteria are you using for mileage when the range extender is running? The 1.4 liter may run, then shut off, then run again. At those times, what are you guessing for mileage? If the Prius gets up to 50 mpg running continuosly, what numbers did you use for the Volt?
If it is less than the Prius, your whole economy section is out the door.
Please provide your proof that the car will not make the 40 miles in normal driving or else be prepared to be questioned about your intent.
Hugo- Things change. it wa a 74 hp engine-generator last yer in Chicago, but GM tells us it is now rated at 71 hp.
As for generator only performance- we want to know that, too! We get a brief test drive in charge depleting (generator) mode this coming Sunday and will write about it right away, but we won't be gin the opportunity this early in the game to do any extended driving; imagine that's gonna have to wait til just before the car goes on sale. GM holds all the keys!
Aurakr - We don't think it will make 40 miles on battery alone at highway speeds because GM has told us that figure is for city-cycle driving. We haven't tested it because GM hasn't given anyone in the media access to a car for that long. As for criteria on mileage extender etc., as the article says, our chief engineer has worked all that up and will be posting an article soon, we'll do a piece alerting you all to that event and providing a link to the piece. As for the engine-generator, we don't think it will run, shut off and run again, etc., during a single trip except, possible, for some very short periods because, as GM explains it, it is not tasked with recharging the battery, its job is simply to pour out electricity for the motor, so there's not much of a recharge for the battery to fall back on once the initial charge is depleted. And no need to question our "intent," it is simply to bring you as much information as we can pull together.
Ok 40 grand car with a twist beam rear axel?
And:
17" in wheels?
Why 17", they want to lose weight. I have a few lbs for them in nice 15" steelies.
John O'Dell:
Thanks for the quick response. If what you said is true, GM will be in for a world of trouble if the car can not go 40 miles in normal driving, their words. I call normal driving both city and highway. If it only goes 20 miles highway, look out.
The question about mileage when the range extender is on. Now if the Prius can get up to and over 50 mpg highway, why not the Volt? What numbers are you using there?
Thanks again. Happy Thanksgiving
Any word, or even guesses, on range verses ambient temperature? How much will the electric range be reduced driving around Detroit in January at 20 degrees F?
John O'Dell:
I find it hard to believe that the engine-generator won't recharge the battery pack. If this is true, the engine will constantly be starting/stopping during stop and go driving with a low battery pack. It would make much more sense to allow the engine to run, charging the battery pack to a level that would allow you to go back to running in pure electric mode.
So since apparently the combustion engine doesnt charge the battery, does that mean that the only way to significantly charge the battery pack is to plug it into the wall?
"I find it hard to believe that the engine-generator won't recharge the battery pack"
Especially since the Volt literature says it does.
http://gm-volt.com/chevy-volt-faqs/
While we're at it, let's back up this statement: "holds sufficient juice to power the motor for up to 40 miles at low-speed driving, less at speeds above 20 mile an hour"
Where do you get the 20mph number from?
This "article" significantly refutes some of the key elements we've learned about the Volt over the last year, but it fails to provide any references. If you're going to post such an article, please back it up.
When I wrote a paper in school, I needed to provide references. I think it's reasonable to expect someone publishing an article on an automotive reference site to do the same.
Brn/120mm - Chevy engineers have been telling us almost from the start that the engine-generator doesn't recharge the battery. If you want to split hairs, it does- as te article says - put a little juice back into the pack, but it doesn't fully recharge the battery because it isn't a big enough powerplant to keep the car's electric drivetrain running at full capacity AND recharge the battery at the same time. As to just how long the pack ad at what speeds te pack will keep the Volt going before the grid-charge is run down, we've gotten numbers that are all over the place. Some GM'ers insist it will be 40 miles at highway speeds. We hope it does. But others who work on the Volt have said the 40 miles is on a city cycle - and the city cycle GM used to get its claimed 230 MPG figure has an average speed of 19.6 mph. If we're wrong and the car does indeed run a full 40 miles at highway speeds on a single battery charge without help from the engine-generator we'll be the first to trumpet it from the skies. But remember, the Volt uses only 8 kwh of its 16 kwh battery - and we have a hard time getting 80 miles out of a Mini E at freeway speeds and it has a 35 kwh battery piack with more than three times the usable energy - 28 kwh.
Smrty - Yup. It get some juice from regenerative action and a little form the motor-generator, but you've gotta plug it in to fully recharge it.
Aurakr - Prius gets 50 mpg plus on highway because it is using both gas engine and electric motors some of the time. We expect the combined city-highway mileage for the Volt to come in at somewhere around 80-90 miles per gallon when all-battery segment of a drive is combined with the portion using the engine-generator. But the engine-generator alone, based on the 280-or so miles of range and the approximately 8-10 gallon tank size that GM keeps discussing for it, would mean that absent the battery it would drink at a rate of around 30-35 mpg. Don't forget, we're making assumptions based on bits and piece of info because GM simply hasn't been able - or willing - to give out final hard numbers.
John,
I think I figured out where the confusion is. I believe you're trying to say, don't expect the generator to bring the battery back up to a full charge.
My contention is that the generator does charge the battery for the purpose of handling the peaks and valleys of the requirements from the electric motor.
If I now interpret you correctly, I believe we're both correct. However it's very easy to misinterpret the article. Just look at people's reactions!
OK, now to this: "230 MPG figure has an average speed of 19.6 mph"
That, I believe. However, it is a leap to take the above and conclude "power the motor for up to 40 miles at low-speed driving, less at speeds above 20 mile an hour". You may or may not be correct, but the conclusion cannot be made based on the EPA test.
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