Elon Musk is CEO of Tesla Motors, the company that has jump started the electric car revolution.  Tesla already offers a 2-seat superfast Roadster electric car, and has recently unveiled a more moderately priced 4-door Model S sedan.

Tesla has never publicly admitted intentions of building an extended-range electric car.  Yet General Motors has it entire future pinned on the hopes of one such vehicle, the Chevrolet Volt.

I had the chance to ask Musk about this.

"We looked closely at a range extender architecture for Model S," he said but added that "it ends up costing about the same in vehicle unit cost, a lot more in R&D and a lot more in servicing."  Further he said it was his opinion that an EREV "turns really bad when the battery runs out and an undersized engine is carrying all the dead weight of the pack," and that it is "neither fish nor fowl and ends up being worse (in our opinion) than either a gasoline or pure electric vehicle."

Musk also debated the merits of an EREV pack versus a BEV pack. "The battery pack in a plug in hybrid like the Volt has to generate the same power as a much larger battery pack in a pure electric vehicle (and thus) has to use a low energy cell chemistry," he said. "The net result is that a 40 mile REV pack is roughly half the size of a 200 mile EV pack."

Finally he criticized the fact that the Volt has to us gas at all declaring "you still have to deal with all the environmental issues of a gasoline engine."

Source (GM-Volt.com)