2007 Saturn Aura Green Line Hybrid: Fuel Economy


Saturn Aura Hybrid Car
Last April we wrote about the 2007 Saturn Aura hybrid. Most of the technical details about the hybrid drivetrain were available, but we ended the post with: "GM has not yet announced performance or fuel economy numbers for the Saturn Aura Greenline Hybrid sedan". Well, now we know.

the Aura Green Line sedan will deliver at least a 25% fuel economy improvement over the non-hybrid Aura XE for a premium of less than $2,500, according to GM.

The non-hybrid 2007 Aura XE, fitted with a 3.5-liter V-6 engine, carries a fuel economy rating of 20 mpg city, 30 mpg highway.

The GM Hybrid Belt Alternator Starter (BAS) system in the Aura Green Line combines an electric motor/generator with a 2.4L Ecotec VVT four-cylinder engine, Hydra-Matic 4T45 four-speed transmission and Cobasys 36V NiMH battery pack.

So 25% would take it to about 25 mpg city, 37.5 mpg highway (though the 25% is probably not split evenly between city and highway).

The main problem here is that they are comparing apples to oranges; they seems to be basing the 25% figure on the Aura XE with the 3.5 liter V6 and not on a comparable non-hybrid 2.4 liter 4-cylinder engine version of the car. Granted, there might not be a 4-cylinder non-hybrid version to compare it to, but still, GM doesn't mention that most of the fuel-economy benefits of the hybrid Aura probably come from the downsized engine.

To be fair, most other hybrid cars have downsized gasoline engines compared to similar models, but they also have more than a 25% improvement in fuel economy to show for it.

The Aura Green Line’s base price is expected to start below $23,000, and will be available at Saturn retailers in spring 2007. [...]

Aura Green Line’s hybrid powertrain is rated at 164 hp (122 kW) at 6,400 rpm and 159 lb-ft (215 Nm) of peak torque at 5,000 rpm.

No word on emissions, which probably be means that the Aura hybrid is not SULEV or AT-PZEV.

You be the judge. Is the 2007 Aura hybrid a promising vehicle, or a disappointment?

::2007 GM Saturn Aura to be Available as Hybrid, ::Saturn Aura Green Line Hybrid to Offer 25% Fuel Economy Improvement Over Non-Hybrid
Standard car article advice: Walk, cycle, carpool, take public transit, car-share, telecommute. Try to live close to the things you need and to where you work. But if you have to own a car, get the most efficient model that fills your needs, drive sanely, combine trips, keep it in good mechanical condition and keep your tires properly inflated.