We love our readers, because they often have eagle eyes far more acute than our own. Take, for instance, Neal Riley.

Reading our article on the 2013 Chevrolet Spark launch, which included official confirmation of the news on the all-electric Spark EV model that we broke last night, he asked:

If the battery is really a 20-kilowatt-hour capacity pack and the car gets 18 miles per kwh as depicted in the dashboard picture, the range computes to 360 miles per charge. Now that would be really great. Am I wrong in my findings?

That's a great question.

Put another way, Neal is asking whether GM has managed to prototype a car that will achieve 18 miles per kilowatt-hour of usable battery-pack capacity, as the GM-provided dashboard image shows.

That would be quite remarkable indeed, since the 2012 Chevrolet Volt range-extended electric car gets only 2.5 to 4 miles per usable kWh. Other major manufacturers' plug-in cars achieve similar ranges per kWh, and we're not aware of any battery electric vehicle that can deliver even 10 miles per kWh--let alone 18.

2013 Chevrolet Spark EV cutaway

2013 Chevrolet Spark EV cutaway

So we wrote to GM on Neal's behalf, asking whether this was a stunning technological breakthrough they'd simply neglected to mention at the launch.

GM's Rob Peterson replied:

While everyone else was asleep, we have managed to disprove the First Law of Thermodynamics, allowing us to move from approximately 4 [miles per] kWh to 18.  The perpetual motion machine is squarely in our sites, and in our product portfolio.

Which made us laugh out loud.

Peterson then continued, "The actual answer is, no. Our graphic is incorrect."

We appreciate a carmaker that owns up to its goofs quickly, as we try to do here.

And there you have it, Neal. Good spotting!


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