2011 Automobile of the Year: Chevrolet Volt

Jim Fets

The ways the wheels turn

The Chevy Volt is a pure electric, a series hybrid, and a parallel hybrid all rolled into one. The heart of its many modes is an automatic transmission consisting of one planetary gearset and three electronically controlled, hydraulically activated multiplate clutches. This ingenious transmission efficiently blends engine and electric-motor torque to drive the wheels with utmost efficiency. All Volt powertrain components -- two electric motor/generators, the gasoline engine, the aforementioned transmission, and a final-drive differential -- are bolted together in a single unit to save space and weight and to optimize NVH characteristics. To provide 25 to 50 miles of pure-electric operation and 300 or so miles of additional range with the gasoline engine running, the Volt has five distinct operating modes:

1. Battery discharging, acceleration or low-speed cruising: With energy provided from the battery pack, the Volt uses only its larger 149-hp electric motor for cruising below 40 mph or accelerating at any speed. A clutch locks the ring gear of the planetary gearset for a 7.0:1 speed reduction and torque multiplication ratio.

2. Battery discharging, high-speed cruising: Like any energy-conversion device, electric motors are more efficient at certain operating speeds. When the Volt exceeds 40 mph, the clutch holding the ring gear is released. A second clutch engages to connect that ring gear to the smaller of the two electric motors. Now both electric motors draw electricity from the battery pack, and the effective gear ratio is numerically lower, reducing the rpm of the primary drive motor.

3. Battery depleted, acceleration or low-speed cruising: The Volt never empties its battery completely; the gas engine starts when the battery is drained to about thirty percent. A clutch connects the gas engine to the smaller electric generator, which provides electricity to the main electric-drive motor. The ring gear is again fixed for a low overall drive ratio between the motor and the half shafts powering the Volt's front wheels. This series-hybrid regime is used for speeds below 40 mph.

4. Battery depleted, high-speed cruising: The planetary ring gear is again released, shifting the drive motor to a higher gear ratio. The engine continues providing the power to spin the generator, which in turn supplies the drive motor with electric current. In addition, the engine supplies torque to the planetary ring gear through the smaller electric generator; hence, some of the gas/engine power goes to the wheels. Operating in this regime, the Volt is both a series hybrid and a parallel hybrid.

5. Braking: Like all hybrids and electric vehicles, the Volt uses regenerative braking to convert unwanted momentum to electrical energy. When accelerator-pedal pressure is reduced or the brake pedal is applied, the main drive motor temporarily operates as a generator and the electrical current produced restores a portion of the battery's charge. - Eric Tingwall

GREAT CHOICE!!!The Volt is BY FAR the biggest game changer in the auto industry since, I guess, the Prius, only this is so far advanced that anyone buying a Prius from here out is simply uninformed. GM has hit a grand slam (finally) with this car and as battery technology improves and the pricing drops (remember plasma TV's @ $6,000 when they first came out?)I see a $25k Volt in the not-too-distant future and when that happens together with improved batteries, it's over for the competition.
@jdmcderm: Automobile of the Year is always a new car. That means our winners have always been on sale for less than a year when announced.@CarGuyAZ: We aren't trying to "push" cars on anybody. With unparalleled access to vehicles, engineers, and executives, we're in a unique position to evaluate products and know what automakers are planning for the future. We know automakers are working on powertrains very similar to the Volt's, and it's GM's profound first step into a new technology that merits acknowledgment.Also, no one at Automobile Magazine has ever insinuated that the Volt will sell in high volumes; Automobile of the Year isn't about predicting the most popular car, as evidenced by past winners like the Nissan GT-R and Audi R8.
Apparently all the automotive magazines must be owned by the same mindless individuals. All the magazines are apparently trying to push the same crap on the American consumer. Do you really believe Americans are going to rush out now in this economy and buy a 40K piece of crap from a company that can't get it's act together? They've already robbed the American tax payers with the auto bailout so why not bail them out with a glowing review of another worthless product that no one with buy even with a government sponsored tax break. I hope you don't consider yourselves journalists. At this point you've become a printed version of an infomercial for GM. Government needs to stay out of the car business and maybe GM too.
What a joke. Automobile Mag writers really are sipping the kool-aid. I'd like to see GM survive, but this car won't save them. Goes 40 miles and then switches to gasoline. That's useless! I still have to use gasoline in one day's worth of driving--isn't the point to get away from that? I'd rather get a Leaf--perfect for a weekend of driving in and around the city (but obviously not long road trips). Do you know which car will save an entire car company? The Jag XJ. That should've been the car of the year.
The Volt truly deserves this "Automobile of the Year" award. Its unique powertrain makes it the only all-electric commuter car (for most U.S. workers) that can also be a family's only car, thanks to its innovative range-extending operation. As for complaints about government tax credits, the Nissan Leaf receives the same consideration, and 60,000 Toyota Priuses have qualified for U.S. government tax credits, too. Fair is fair! True, GM has had serious problems in the recent past, but this car, along with the fantastic new Chevy Cruze and other great, new GM vehicles means that Chevy, Cadillac, Buick, and GMC all deserve the chance to re-establish the trust and admiration of the American public. Thank you, Automobile Magazine, for recognizing the importance of the Volt's technology in advancing the future of the automobile as we know it.
A company,which robbed its shareholders, bondholders and the taxpayers, together with the UAW, makes a sos-so car, does not even deserve mentioning. Ten years late, five years behind and a totally wrong concept from Government Motors is garbage. Anything that has to be sold to people by giving them money from their neighbors $7,500.00 to buy an overpriced dead end technology is a crime, only politicians can commit, without being hanged.
Of course it's the Automobile of the Year. Ten years from now, when there are scores of other cars on the road that are just like it, all the negative naysayers in the world couldn't and wouldn't have been able to change the Volt as the best choice in 2010 for AOTY - it's that groundbreaking, that smart, that good of a design concept, making everyone elses hybrids look bad by comparison. Forget your Gov't Motors hangups and your anti-anti American made bias and recognize GM has a better idea - and they executed it very well (this time). Give them credit where deserved, they have outdone the competition. But if, in your closed minded stubborness, you should find yourself one day sitting by the side of the road, out of juice, waiting for the tow truck in your all electric Leaf (or whatever)and you spy one of these Volts pass you by, just remember, you read it here first.
Terrible choice. Wouldn't buy anything from Government Motors until it is returned to private ownership. It is ridiculous to think of paying $40k+ for a car that only goes 40 miles on electric and then it goes to gas. The only way it will sell is with government incentives which are taken from the rest of us taxpayers to make it cheaper for a few. If it was on a level plane, few if any would sell.
You guys have officially jumped the shark. Because the Volt was delayed, the PR wizards at GM have whipped you all into a frenzy. Can we see if the car works as advertised and stands the test of at least a year's time on the road before we start heaping accolades on it? I want GM to be successful also, but willing it into existence don't make it so. Bottom line, you wouldn't have given this award to an unproven new model from any other carmaker. However, if you turn out to be right, you'll be heralded as geniuses.

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