GM Overestimates Chevy Volt Fuel Efficiency By...130 MPG?

In August 2009, General Motors CEO Fritz Henderson announced that the new Chevrolet Volt, GM's first electric car, would get an estimated 230 miles per gallon. The faltering car company hoped that the exceptionally high government mileage rating could give the Volt a major sales boost. "Having a car that gets triple-digit fuel economy can and will be a game changer for us," Henderson predicted.

But more than a year later, the Chevy Volt is finally ready to hit sales lots, but may give Henderson his own sticker shock.  The EPA mileage rating for the Volt now stands at 93 mgp, significantly less than previous predictions.  The Volt's rating comes just days after Nissan's own electric vehicle, the Leaf, received an estimated 99 mpg rating.

So why the huge discrepancy?  GM claims it has been working cooperatively with the EPA for years, but the agency reportedly says it had not tested a Volt until just recently.

According to CNN, drivers will be able to drive the Volt for about 40 miles using the car's lithium-ion batteries.  For those driving more than 40 miles at a time, the Volt will use gasoline.

If a car is driven 50 miles in a day, the first 40 miles will use gas and the last 10 miles will use 0.2 gallons -- the equivalent of 250 miles per gallon. But, if the driver drives 80 miles, total fuel economy drops to about 100 mpg; 62 mpg for 300 miles.

So while it's official sticker estimate is significantly lower than the estimated 230 mpg GM boasted a year ago,  the good news for GM is that they are now ready to hit sales lots.  The bad news (for consumers)?  It retails for more than $40,000.