2007 Saturn Aura Hybrid vs. 2007 Nissan Altima Hybrid vs. 2007 Toyota Camry Hybrid

Comparing hybrid sedans is a little like pitting Rush Limbaugh against Al Gore in a Thunderdome-style death match. Manufacturers are responding with midsize sedans - the most popular car segment in the largest car market in the world.

We've assembled the three big players in this segment: Nissan's 2007 Altima Hybrid, Saturn's 2007 Aura Green Line and Toyota's 2007 Camry Hybrid. Just like the standard Camry, the hybrid version comes loaded with features like dual-zone climate control and Toyota's Smart Key system with push-button start. Our test car also has plenty of options, including the $1,300 Leather Package and $1,200 voice-activated DVD-based navigation and audio system (with satellite radio). At $30,535 as tested, Nissan's Altima Hybrid undercuts the Camry by only $132. All three cars come standard with four-wheel antilock disc brakes, head curtain and side airbags, traction control and stability control. Regenerative braking, which turns kinetic energy from braking into electrical energy to charge the hybrid system's batteries, is a key feature in most hybrids and all three cars utilize it. Some editors even thought of the Camry's fuel economy display as a personal challenge to their driving skill.

Fuel economy contributed a major amount to each car's overall score, while performance was scaled back accordingly. As-tested price, the most heavily weighted category, accounts for 30 percent of each car's total score.

All Hybrids Are Not Created Equal

Understanding the differences between the two types of hybrids tested here is critical to both making an informed purchase decision and reconciling the differences in each car's performance and efficiency. Both the Camry and Altima use Toyota's Hybrid Synergy Drive. The Camry Hybrid comes standard with a 2.4-liter four-cylinder engine rated at 147 hp and 138 pound-feet of torque that augments its 30-kilowatt electric motor. First, it allows the car to be propelled entirely on electric power under many conditions and many speeds, and this saves fuel. Its unique CVT allows power to come from either the gas engine or electric motor, providing the ability to blend power sources for optimal efficiency.

GM's hybrid system combines the base Aura's 2.4-liter four-cylinder power plant with an electric motor-generator. The Aura's NiMH battery pack produces 10 kilowatts of power.

The Aura's electric motor is used to start the gasoline engine and can add small amounts of power under high-load conditions. Like the Camry and Altima, the gasoline engine shuts off under certain conditions and the electric motor restarts it. The Camry and Altima are each certified as Advanced Technology-Partial Zero Emissions Vehicles (AT-PZEV). Meanwhile, the Aura is certified as a Low Emissions Vehicle (LEV).

First, we performed a test in which all three cars were driven over two road loops - one highway (120 miles) and one city (50 miles). Driving in a group and using the same driving style and similar speeds ensured a controlled environment for all three cars. Both the Camry's "ECO" button and the Aura's "Hybrid A/C" button, which limit the ventilation system's energy consumption, were engaged. The combined fuel economy numbers produced during these tests were used in our fuel economy scoring, which contributes to 15 percent of each car's overall score.

Toyota proved it's got the fuel economy game wrapped up, as the Camry produced the best combined mileage of our test group with 43.2 mpg over both loops - 44.5 mpg in the city and 42.6 mpg on the highway. The Altima's fuel economy in the city actually proved marginally better than the Camry's at 47.3 mpg, but its 38.1 mpg on the highway dropped its combined rating to 40.1 mpg.

The Aura wasn't even close. Its combined fuel economy was just 26 mpg, largely as a result of its 18.9 mpg in city driving - where it doesn't benefit from true electric-only propulsion like the Camry and Altima. On the highway loop, the Aura produced 31.5 mpg.

Second, we calculated observed fuel economy over our entire time with each car, just as we do with all of our road test vehicles. The Camry again came out on top, producing 32.6 mpg. At 31.5 mpg, the Altima is a close 2nd, while the Aura lags behind at 24.5 mpg.

3rd Place: 2007 Saturn Aura Green Line Hybrid

The Aura is a big step forward for GM when it comes to the midsize sedan segment. The factor that hurts it worst in this test, however, is that its fuel economy simply doesn't compete with other hybrid sedans. Equipped with a mild-hybrid powertrain that lacks true electric-only propulsion, the Aura burdens its gasoline engine more than its full-hybrid competition. Even though our scoring system emphasizes the importance of price more than any other factor, the Aura's $7,500 price advantage over the 2nd-place Altima isn't enough to overcome its deficit in fuel-efficiency.

We'll admit that it would take more than 18 years to recoup the price difference between the Altima and Aura in fuel-cost savings alone. (We're using the current average U.S. fuel cost, a rate of 15,000 miles per annum and the same observed fuel economy we achieved - 31.5 and 24.5 mpg, respectively.) Handling and braking numbers brought the Aura closer to its competition. It stops from 60 mph in 139 feet - 3 feet longer than the Altima and 5 feet longer than the Camry. The Aura did win points with several features that the Altima and Camry simply don't have. Its mild hybrid system requires fewer batteries, which are traditionally packaged in the trunk of most hybrid sedans. The Aura also has a 60/40-split folding rear seat, which the Altima didn't have, while the Camry makes a half-hearted attempt with a split-folding design that's partially blocked by batteries. The Aura is also the only car in the group that comes standard with an emergency assistance system (OnStar).

2nd Place: 2007 Nissan Altima Hybrid

The Altima's logbook notes are clear: "Finally. A hybrid with decent steering and a responsive chassis. Nissan has proven otherwise with the Altima Hybrid, which takes 2nd in this test by a mere 2.3 points. Because the Camry gives you more features for the same money and produces marginally better fuel economy. Both the Altima and the Camry are available with navigation, but our Camry test car delivers the goods for only $132 more than the non-nav-equipped Altima. The Altima's batteries also consume significant cargo room in the trunk, reducing its volume to 9.1 cubic feet compared to the Camry's 10.6 cubic feet.

At the track the Altima produces impressive acceleration, proving that hybrid powertrains can increase performance as well as efficiency. Its best-in-test 0-60-mph sprint of 7.6 seconds and quarter-mile performance of 15.6 seconds at 91.5 mph were considerably quicker than the 2nd-place Camry.

Around the skid pad, the Altima ties the Camry at 0.76g but is slightly quicker through the slalom (61.4 mph vs. 61.0 mph). It takes 2 feet more to stop the Altima from 60 mph than it does to stop the Camry (136 feet. vs. 134).

1st Place: 2007 Toyota Camry Hybrid

It's the Camry's abundant features, comfortable ride and fuel-sipping efficiency that take it to the top of the podium in this test. Just like the standard Camry, the simple fact is the Camry Hybrid gives you a lot of car for your money.

Part of the value comes in the form of real-world performance. The Camry hits 60 mph in 8.4 seconds and stops the quarter-mile clock in 16.2 seconds at 87.5 mph. Sixty to zero required 134 feet - the shortest stop in this group. And despite a softer ride, the Camry nearly equals the Altima's handling numbers by circling the skid pad at 0.76g and splitting the slalom cones at 61.0 mph.

The Camry Hybrid is also refined and easy to drive in every way a midsize sedan should be. There's ample driver and passenger space and plenty of adjustability in everything from the seats to the pollen-filtered climate control. The Camry isn't the most fun-to-drive car here, but its value and utility prove once again that Toyota understands the midsize sedan segment better than any other company.

Details like an Atkinson-cycle gasoline engine (a distinction that helps the Camry nip the Altima in fuel economy) and packaging designed to accommodate the hybrid batteries with minimal intrusion into the interior speak volumes for Toyota's commitment to hybrids. And in a game where commitment translates directly into real-world benefits like preserving natural resources and reducing emissions, we'll give it the win every time. Even Rush couldn't argue with that.