Is it or is it not? That is the question being asked this past week as news comes the Chevy Volt may not be as electric as it claims to be. Edmunds says GM has lied: "it isn't as electric as GM has been saying for the past three years."
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| Electric, Hybrid, or Neither? |
GM has fired back in a statement: "There is no direct mechanical connection (fixed gear ratio) between the Volt’s extended-range 1.4L 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 percent improvement in highway fuel economy." and "If the traction motor is disabled, the range-extending internal combustion engine cannot drive the vehicle by itself."
Seemingly at the heart of the debate is what the Volt can call itself. GM claims the Volt is an electric car (ignore the gas engine behind the curtain, please). Edmunds (and others like the NY Times) claim the Volt is a hybrid, really a plug-in hybrid. But that's not really the problem here.
Back Story, the Birth of an E-REV
The story I have had in my head based on all I've read and learned about the Chevy Volt E-REV goes like this. The Volt is a plug-in hybrid vehicle, but a variation within that framework, one I had come to realize deserves a new name to distinguish it from other plug-in hybrid vehicles. The Volt runs on electric power alone for 40 miles (electric power you have stored up overnight by plugging in). After that, the electricity is produced by a small gas engine which supposedly just recharged the battery pack.
Shocking Truth? Or Just Media Bias?
It's shocking, to me and others, to find that story isn't quite true. According to Edmunds, the gas engine is assisting the electric motors at highway speeds (at or above 70 mph ). Kicking Tires points out "there's a power-split device similar to the type in hybrids from Toyota and Ford. "
It doesn't really matter if the car can only move if the electric motor is also running. ("The engineers say yes. They say the arrangement produces a slight increase in efficiency, but they emphasize that it's not as if the gas engine takes over from the electric drive. The electric drive is indispensable, at high as well as low speeds, they say." Source: MSNBC") What matters is GM has been clear for years now the gas motor would not be capable of pushing the car.
Truth or How Dare They?
And the real kicker, does this mean the gas engine will kick in at highway speeds even in the first 40 miles? Can you really call a car like that an E-REV? What's exciting about the Volt is the ability (if you only travel less than 40 miles a day), you can own an electric car without the 'range anxiety' an all electric car brings. The Leaf goes for 100 miles, but after that you need to recharge. In other words, you need to find a plug and about 4-8 hours of time. The Volt just needs to pull into a local gas station if you don't have a handy plug.
And that's why most of the questions I've seen about the gas engine are 1) can it be even smaller? and 2) what if you don't go over 40 miles for a year or two? Doesn't the gas go stale?
That's the way people are thinking about the Volt.
Truly an Electric for 40 miles or not?
But if that's not true, if your commute involves highway driving at 70 mph, and the gas engine is going to turn on anyways... Well, now we have a real problem. This is what the true furor is about.
Consumers are hoping for an electric car for most days, but a gas car when you need it to go farther. What if they don't use gas for a couple of years? GM has said they have thought of this and it won't be an issue. Now I'm wondering if this is why they were so confident about that.
"The buzz around the internet — and at this event — suggests the world will soon come to an end because the Volt isn't what people thought it would be, that it's somehow a lesser vehicle. I don't see it. Once the engine starts, the point is efficiency." (Source: Joe Wiesenfelder at Kicking Tires) With all respect to Joe, that's not the point at all of the Volt. A true plug-in hybrid electric vehicle will be more efficient than an E-REV.
If the gas engine only 'assists' the electric motor after you are in 'extended range', then the furor over the name calling (what's in a name, after all?) will be over in my mind. The gas engine is already on and what difference does it make that the engine is not only recharging the battery pack, but it's also helping move the car a little bit increasing the efficiency.
What's in a Name
The E-REV definition separates the Volt from an all electric car. It also separates it from a plug-in hybrid (like the one expected from Toyota in the next year or so). But only if the gas engine doesn't assist at high speeds in the first 40 miles. If it does, then the Volt will need to be relabeled as a plug-in hybrid. Because that's what it would be, whether GM wants it to be called that or not. Toyota and Ford hybrids already drive at low speeds on all electric power as just hybrids. The difference maker for the Volt was being able to go any speed up to 40 miles (you're miles will vary).
Sidenote:
BTW (To Mark Phelan at freep) who says "If you don't believe Parks and the independent testers who've driven the car, though, ask the federal government. It has approved the Volt for a $7,500 tax credit that only applies to electric vehicles. Hybrids need not apply." That's not true. The credit is not to 'electric cars' and the Toyota Prius plug-in will probably qualify for the tax credit.
Read More
To read more on the controversy: Money Times, IB Times, US News, Kicking Tires, Earth Techling, GM, freep
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