How the Chevy Volt Will Transform Fuel Economy

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A novice's read of how the Volt works would reveal that the engine does not provide power to the wheels; it powers a generator and the resultant electricity is stored by the battery and used by electric motors to turn the wheels. This allows excellent performance because the engine can run at at an optimal speed for maximal gas mileage while the battery stores power when bursts of acceleration are needed. How can US News publish something that shows such ignorance of even the basics of why the Volt is an important advance? Please focus on transforming yourself into a source of truth. Your correction statement is not reflected in the article. A quality publication would actually FIX the misstatement in the article. The Volt appears to be doing much better than your authors and editors--and GM went bankrupt.

chuck kennedy of CA 1:11PM August 27, 2009

I too found the error mentioned by the readers, i found it on yahoo, and could not post a comment there. I decided to see if the error was fixed on this website, and it is, but please please understand that yahoo readers are NOT reading the clarified article!! Hard to believe that a fundamental (and pretty simple) concept was not understood. "Ugh", says it all.

Anthony C. of PA 9:47PM August 24, 2009

The line in the article stating "The small engine is likely to be underpowered" is ridiculous, because if the author had done any research on the Volt at all, he would know that the engine does not power the vehicle, it simply charges the battery. When the gas engine is on, the electric motor still propels the car.

Anthony Myers of IL 3:00PM August 24, 2009

Weight of the battery is offset by the fact there isn't a drivetrain. Way to not discuss the series-hybrid part at all.

Andrew Rydholm of PA 2:07PM August 24, 2009

Very poor jounalism with little attention paid to depth of facts;
for example--it won't be a "wheezer" as it doesn't use the engine for
power -- it uses it to charge the battery and keeps running on electrical
power.
Is this article a true example of the "in depth" reporting of US News?
Ugh.

Vaughn Folkert of NY 3:46PM August 22, 2009

You asked "we’d really want to know how many miles per kilowatt it average, MPK. Or perhaps it would be kilowatts per mile, KPM."
GM press release said this: "* Tentative EPA methodology results show 25 kilowatt hours/100 miles electrical efficiency in city cycle"
And "I'm not sure which"? Really? US News & World report allows you write articles where you don't know what you are talking about? Why would I pay for that kind of writing?

Dag Johansen of CA 1:27PM August 21, 2009

Correction, the EV1 got 183 MPG equivalent. 36,650 Watt-hours per gallon / 200 Watt-hours per mile = 183.25 miles per gallon.

Jeff Chan of CA 11:51AM August 21, 2009

There is a very bad factual error in your piece where you say General Motors' pure electric vehicle, the EV1, got the equivalent of 60 MPG. The EV1 used about 200 Watt-hours per mile, which is equivalent to about 141 MPG. This is easily confirmed by the fact that the Gen II NiMH battery capacity was 26.4 kWh, and it had a range of about 130 miles. The energy density of gasoline is about 36,650 watt-hours per gallon. The conversions are simple algebra.
Also electric energy is measured in Watt-hours, not Watts. Watts are a measure of power. Energy is power integrated over time.

Jeff Chan of CA 11:41AM August 21, 2009

40 miles on battery may be sufficient for many commuters, but does GM only expect to sell the Volt in SoCal and Florida? When the temperature drops below freezing, that 40 miles range may drop down to 20 or less. How about keeping the cabin warm. At zero degree it will probably take a few kWh of energy just to bring the interior temperature of the car up to a comfortable level. All vehicles suffer from lower milage in Winter but I would think the effect of low temperature on electric vehicles will be even higher than on gasoline engine vehicles.

Tony 6:55PM August 20, 2009

But still, not that complicated.
For me, half my miles are *beyond* the 40th mile assuming I can charge at the office. If I can't charge at office and charity, then 3/4 of my miles are beyond the 40th mile. That means the vast majority of my energy expense will be gasoline.
A friend almost never drives more than 10 miles past a recharge opportunity. The Volt has a much larger battery than she needs. All her expense will be electricity.
So how do I calculate one single $$ per mile for the two of us? Let alone for all people everywhere?

Robert of CA 6:11PM August 20, 2009