Understanding the Karma's 100 MPG promise

Car And Driver said:

A stroll down the length of the Delta concourse at LAX presents travelers with no fewer than five banner ads featuring Fisker’s sexy Karma. An image of the slinky four-door hybrid is accompanied by a claim that the car will achieve 100 mpg, which to some people seems downright dubious and to others sounds like Holy Grail material. Well, as it turns out, it may be a bit optimistic after all, at least officially.

At this year’s Frankfurt auto show, Fisker revealed that, according to the formula applied by the Society of Automotive Engineers, the Karma would achieve the fuel-economy equivalent of 3.5 liters/100 km, which in English translates into 67.2 mpg, only two-thirds of Fisker’s claim. D’oh!

Fisker, however, is quick to point out the obvious: if you charge the thing every night and drive in Stealth mode all the time and fully recharge it before the battery runs out, you may never use gasoline at all, so theoretically, the 100-mpg claim remains more than achievable. Thus, the Irvine, California-based company still stands behind the 100-mpg figure: “We wanted to communicate a number based on something solid and tangible. The 67.2 [figure] is based on current SAE formulas combining city and highway mileage, which are expected to strongly influence final EPA calculations still under development. Stand-alone city figures are much higher. 100 mpg is an achievable annual average that Karma drivers should expect to see so we will continue with that data point,” said Russel Datz, Fisker’s director of public relations.

We sort of expected that even amid the advances in battery technology we’ve seen of late, once push came to shove—and estimated weight for the production Karma ballooned to some 5000 pounds—100 mpg would be rather difficult to achieve in practice once the Karma finally hits the market, which is now scheduled for Summer 2010. (Yes, that’s more than six months later than predicted and only a couple of months earlier than that other plug-in deal, the Chevy Volt.) Still, even at two-thirds its intended efficiency, it remains on track to be the quickest, most emotional, and sexiest hybrid ever. And we can’t wait to get our hands on one to see just how fast we can drain the batteries and the tank—in the name of science, of course.

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