The Saturn Aura is lending an aura to General Motors. As a svelte newcomer sedan with sports car tendencies, it has quickly carved a notch for itself in the ranks of top award winners. In a "Green Line" rendition, following the Fall introduction as an '07 newbie, it is aiming to clean up the spectra of pollution from vehicle emissions.

That's a tall order for any single vehicle. But en masse with other earth friendly technologies it's bound to make a difference. It follows the path of GM's Silverado and Sierra pickups using mild hybrid technology. Unlike Ford, with the hybrid Escape and Mercury Mariner that are "full" hybrids capable of driving on electricity alone, the Aura essentially uses a larger electric start-er motor for an acceleration boost, and a 36-volt Nickel Metal Hydride (NiMH) battery for electric storage. It allows the drive system to halt at a complete stop rather than idling, such as at a traffic stop, then restarts when the accelerator is pushed. Additional battery charge is gained from the vehicle's system of regenerative braking that captures electricity from friction.

Choosing the term "Green Line" (like the Saturn Vue) has to be a brilliant move for GM. It can gain the image without the more complicated technology of a full hybrid system. And while it's not the most advanced or comprehensive hybrid system, the midsize Aura sedan does something most competitors don't. It comes in at a low enough base price to make an earth friendlier vehicle attractive for more buyers without losing the size and panache of an attractive, European looking sporty vehicle. In Green Line mode, it earns 28 city and 35 highway EPA mileages numbers or, according to GM, as much as a 30 percent fuel economy gain over the V6 powered Aura XE model (not the upmodel XR). The Green Line Aura has a base 2.4-liter four, and maximum combined horsepower of 164. A $1,300 one-time federal tax credit could make its entry price of $22,695 even more appealing.