Is Chevy Volt A Hybrid? Electric? Bit Of Both?


Is it or isn't it? Chevrolet unveiled its new Volt to the press last week, but revelations about the intricacies of the electric motor and small gas engine under the hood have some arguing that the company has a launch problem on its hands: they say the car is not a pure electric vehicle and Chevrolet should have made that clear at the outset. The car is, in fact, powered by an electric motor, with a small gasoline engine that comes on when the battery approaches depletion after about 60 or so miles of electric-only driving.

What has some observers riled is that on its extended-range mode the car's gasoline engine sometimes helps turn the wheels as well. Thus, semantically, the car's a hybrid -- not an electric, they argue.

A site called Green Car Advisor reportedly noted this in June, but with the weekend event, where the company's technical explication included news about the car's extended range capabilities -- and the fact that under those circumstances the gas engine helps turn the wheels -- the Web started the echo machine, with terms like "Volt Gate" banging from site to site like a ping-pong ball.


advertisement's InsideLine said General Motors had duped the press: "Even conceding that all engineering projects involve compromise and chalking that phrase up to marketing hyperbole, the Chevy Volt isn't as electric as GM pretends it is," said the column. "And it isn't as electric as GM has been saying for the past three years." The article went on to say the Chevy Volt is a plug-in hybrid with more in common with Toyota Prius "than the marketing hype led us to believe."

The automaker responded with a release noting that "some confusion has emerged about details of the Volt's drive technology," per a company release. GM explains that "the engineering of the Voltec electric drive unit is very sophisticated. As part of the media launch, we're diving deeper into how the system works than we have in the past. We did not share all the details until now because the information was competitive and we awaited patent approvals."

GM argues that "electric vehicle" still fits because the drive train doesn't involve direct mechanical connection between the 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% improvement in highway fuel economy."

Pamela Fletcher, GM's global chief of global engineering for Volt and plug-in hybrids, tells Marketing Daily that the gist of the technology is that there are two ways to direct power flow through the Volt's drive unit in range-extending mode.

"First, we pull energy through the battery to the wheels. At the same time we have an internal combustion engine connected to the generator motor replenishing the battery." She says that method is fine at lower speeds but becomes terribly inefficient at high speed, where that configuration becomes like rowing a boat with an oar that, rather than dipping in the water, connects to another oar that pulls through the water.

"It's just very inefficient," she says, explaining that power must take a circuitous route to get to the wheels. "Instead, when we get to higher speeds, we have clever solution where we put the combined power to the wheels on a planetary gear set."

Jeremy Anwyl, CEO of, says all of that definitely makes for a better vehicle. However, it also makes for a hybrid, at least under certain circumstances. "I think the confusion is an exercise in semantics," he says. "And it flubbed the launch of the Volt. GM has made a point of coming in here over and over, selling us story that the Volt is not a hybrid -- not another version of Prius, but that it's an electric vehicle that only charges the battery. I think part of the reason our editors are wound up about it is we bought it. And repeated it."

Anwyl speculates that GM made a late-in-the-day design change in Volt that increases its efficiency at high speeds, operates more flexibly, "and makes it a better vehicle. What they should have done is gather media and say, 'Next Sunday we are going to discuss tech behind Volt and but we want to tell you that we are making changes and what we originally told you is no longer the case.' It would have been a non-story."

He argues that the new press release saying GM was mum for competitive purposes "is the absolute worst way of going about it. In an era of transparency, with the Internet, there was nothing wrong with telling people what happened."

Fletcher says the vehicle's architecture underwent no late changes. "We were directed after Auto Show in 2007 to figure out what it takes the make the Volt 'real.' We worked very fast to come up with this arrangement, and applied for a patent on it in September 2007.

"Not many weeks ago, that patent was made publicly visible. The simplest way to view this is that if you take out the gasoline engine, the Volt will work. If you take out the electric engine, it will not. That gasoline engine won't turn the wheels of this car."

On Oct. 12, Edmund's AutoObserver newsletter said the whole "esoteric" classification argument obscures both the engineering achievements the vehicle represents as well as the intrinsic challenges Chevrolet faces marketing it, including price, infrastructure, and consumer's wariness about new technology.

"The dust-up is unlikely to affect Volt purchase intenders," says the article. "But after a day of driving Chevrolet's otherwise profoundly competent new-age sedan, there are reasons to see impediments to widespread adoption."

1 comment about "Is Chevy Volt A Hybrid? Electric? Bit Of Both? ".
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  1. Matthew Munoz from Internet Brands, Inc., October 13, 2010 at 7:24 p.m.

    Well, its mainly electric. Its going to be awesome.

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