Could the EPA cripple the Chevy Volt?
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Word around Detroit is GM and the EPA are apparently duking it out over the Chevy Volt. The problem is this: Is the Volt an electric car or a hybrid? How you define the Volt is important, because it dictates how the official EPA fuel-economy numbers will be calculated.
Strictly speaking, the Volt is a hybrid in that it is an electric vehicle with an on-board internal-combustion engine (likely a version of GM's 1.4L Family Zero four). The internal-combustion engine, which is connected to a generator, acts as a range extender when the Volt's lithium-ion battery pack runs low on power.
The Volt's electric drive unit is designed to run 40 miles purely on the power from the battery pack. After that, then the internal-combustion engine kicks in, generating enough electricity to power the electric drive for what GM says is hundreds of miles more.
Unlike a hybrid like the Prius, which uses its electric motor, gas engine, or a combination of both to turn the wheels, the Volt's wheels are turned only by its electric drive unit.
Now, here's the rub: Reports suggest the Volt can make it through the EPA test cycle -- which from 2008 includes high-speed running, air-conditioning load, and cold-start tests in addition to the city and highway cycles -- with the internal-combustion engine running about 15% of the time.
The straightforward calculation gives the Volt an EPA fuel-consumption rating somewhere north of 100 mpg. But the EPA apparently wants to certify the Volt differently, insisting it finishes the test with the batteries close to full charge. That drops the calculated fuel consumption to just under 48 mpg, because the internal-combustion engine would have to be run essentially all the time to keep the batteries near full charge.
GM argues, with some justification, the EPA's methodology does not reflect the duty cycle for which the Volt was designed. Many consumers, insiders insist, may never have the internal-combustion engine come on at all if their total daily commute is 40 miles or less, or if they recharge the car at their workplace.
The problem is if the Volt goes to market with an EPA rating that is not substantially better than can be achieved by hybrids, diesels, or other small cars, GM insiders worry consumers may not see the value in the car's near-$40,000 price tag.
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