It's the big headline currently on GM's media news site:
"2011 Chevrolet Volt Reinvents Automotive Transportation In A Complete No Compromises Electric Package"
Um, well, no. Even conceding that all engineering projects involve compromise and chalking that phrase up to marketing hyperbole, the Chevy Volt isn't as electric as GM pretends it is. And it isn't as electric as GM has been saying for the past three years. You know, GM statements like this one:
"The Chevrolet Volt is not a hybrid. It is a one-of-a-kind, all-electrically driven vehicle designed and engineered to operate in all climates."
In fact the Chevy Volt is a plug-in hybrid and it has more in common with conventional "series-parallel" hybrids like the Toyota Prius than the marketing hype led us to believe. There are circumstances in which the Volt operates with the internal combustion engine directly driving the front wheels. That's right, like a Prius.
At the heart of the Volt is the "Voltec" propulsion system and the heart of Voltec is the "4ET50" electric drive unit that contains a pair of electric motors and a "multi-mode transaxle with continuously variable capacity." This is how GM describes it:
"Unlike a conventional powertrain, there are no step gears within the unit, and no direct mechanical linkage from the engine, through the drive unit to the wheels."
The 4ET50 is, however, in fact directly bolted to the 1.4-liter, four-cylinder Ecotec internal combustion engine. When the Volt's lithium-ion battery pack runs down, clutches in the 4ET50 engage and the Ecotec engine is lashed to the generator to produce the electric power necessary to drive the car. However, under certain circumstances — speeds near or above 70 mph — the engine will directly drive the front wheels in conjunction with the electric motors.