High-Tech Delivers Fuel Efficiency

(CBS)  New technologies are enabling motorists to guzzle less gas as they hit the road, helping them where they truly feel it – in the pocketbook.

David Champion, the director of the Consumer Reports Auto Testing Facility in East Haddem, Conn., pointed to the Toyota Prius as an example of a "hybrid" car; it uses both a gas engine and electric motor.

The result? Forty-four miles per gallon, overall.

Champion explains that, as you drive, a computer in the hybrid determines whether you should be using the battery, or gas, or both. When you slow down, the braking energy is delivered back into the motor and recharges the batteries. You never have to plug in, and it gets better mileage in the city than on the highway, the opposite of most vehicles.

The Prius sells for about $23,000.

Another "new" technology, actually isn't: diesel. Champion showed the Volkswagen Passat, which uses diesel fuel in attaining 28 miles per gallon.

Diesel vehicles aren't quite as efficient in the city, but fare better on the highway. So, if you commute many miles each day, the diesel will give you better mileage.

BMW, Mercedes and Jeep have their own diesel vehicles.

Champion notes that diesel used to have a poor reputation. In the '70s, engines made to use gas were also were made to use diesel. The internal stresses were greater on the car. Today, designers have come up with engines that use only diesel, for diesel vehicles. And those vehicles are very fuel-efficient. In Europe, more than 50 percent of vehicles are diesel.

Diesel can cost more than conventional gas, but not always, Champion adds.

The Passat's sticker price is in the $25,000 range.

Champion also filled viewers in on "cylinder de-activation," used in vehicles such as Chrysler's 300 C sedan, which Champion displayed. It gets 16 miles per gallon. That's not great, but better than such a big car would get without the de-activation.

When you accelerate, it runs on all cylinders -- 4, 6, or 8. But when you're in cruise mode, it turns off 4 cylinders. So, because you're not running on all cylinders all the time, you save fuel. These vehicles generally get about 10 percent better fuel economy. The Honda Accord Hybrid and Honda Odyssey mini-van use the cylinder de-activation. GM has it in pickup trucks.

The 300 C goes for roughly $38,000.

Besides those three new fuel-efficient technologies, Champion points out, all lighter vehicles get better fuel economy. Big, heavy SUVs tend to be borderline for fuel efficiency. Sedans are better than SUVs, because there is less aerodynamic drag.

Which vehicles fared best when Consumer Reports put them through their paces to gauge their fuel efficiency?

1. The Honda Insight (manual transmission) - 51 mpg overall
   
   
2. The previously mentioned Toyota Prius - 44 mpg overall
   
   
3. The Toyota Echo (manual transmission) - 38 mpg overall
   
   
4. The Honda Civic Hybrid - 36 mpg overall
   
   
5. The Scion xB (manual transmission) - 32 mpg overall

Also on The Early Show Wednesday, viewers get fuel-saving tips from AAA's Robert Sinclair, and Trish Regan looks at factors fueling the steep gas price rise -- and how far it may go.