Fuel Efficient Cars Need Not Be Lighter

by Alex A. Kecskes

Will raising a vehicle's fuel economy reduce its safety? In the rush to boost MPG, the automotive industry has often reduced the weight of its vehicles. After all, it takes less fuel to move a lighter vehicle from point A to point B. But this has made the drivers of these cars more vulnerable to sustaining injuries in crashes. The good news is that automotive engineers are working on alternatives to continually trimming a vehicle's weight.

The Union of Concerned Scientists recently designed a minivan that relies on existing technology to boost fuel economy and lower greenhouse gasses--without altering the weight of the vehicle. Called the Vanguard, the minivan included cylinder deactivation, turbocharging, and tires with lower rolling resistance--technologies that engineers noted could be applied to all types of vehicles without a significant increase in cost.

A 2002 National Academy of Sciences study projected that within 10 to 15 years, the auto industry could be making a 34 mpg midsize SUV, a 37 mpg minivan, a 29 to 30 mpg pickup and a family car that tops 40 mpg.

Automakers insist that fuel-efficient cars must be lighter, smaller, or both, ignoring things like better aerodynamics and variable valve lift and timing. But others disagree, saying that engineering improvements, not weight reduction are key. Just look how SUVs, once infamous for lethal rollovers, roof collapse, and sluggish braking, have been made safer through improved technology and engineering—and not by boosting their mass.

For an additional perspective, check out this video: