AUGUST 2008

Study confirms benefits of lightweight aluminum use in auto bodies

Consumers could save fuel and money while reducing carbon emissions through greater use of low weight aluminum in hybrid- and diesel-powered vehicles, according to a new study released by The Aluminum Association, Inc.

It is well known that diesel and hybrid powertrains provide better fuel economy, but at an increased cost to the consumer. In addition, at equivalent vehicle performance levels compared to a gasoline engine, the advanced powertrains have a payback period of several years. The study titled, “Benefit Analysis: Use of Aluminum Structures in Conjunction with Alternative Powertrain Technologies in Automobiles,” specifically demonstrates that by reducing the weight of the vehicle, the power requirements can be correspondingly reduced, leading to a more affordable powertrain and vehicle, with a shorter payback period.

“With sky-high fuel costs expected over the long term and intense consumer pressure demanding long-term solutions, the time has come to rethink the basics of vehicle design,” said Steve Larkin, president of the Aluminum Association. “Aluminum builds a better car, and this study demonstrates that high-strength, low-weight aluminum offers safe and affordable alternatives for the next generation of vehicles, compared to the heavier, less-efficient vehicles on the road today. If automakers opt to reduce the weight of vehicles with next-generation hybrids and diesels through greater use of aluminum, consumers will be “paid back” faster at the gas pump, compared to the payback time associated with the added costs of today’s heavier hybrids and diesels.”

The study, conducted for the aluminum industry by IBIS Associates, was released during a panel discussion with the Washington Automotive Press Association. The study analyzed the impact of vehicle mass reduction on the cost and power requirements of modern diesel and hybrid powertrains.

“Our study revealed impressive fuel economy gains of 46 percent in diesel-powered vehicles and 51 percent in hybrid-powered vehicles complemented by aluminum structures when compared to existing gasoline-powered vehicles,” Larkin added. “While the aluminum-bodied hybrids’ upfront costs would be more than the aluminum-bodied diesels, they offer significant potential for fuel economy gains and related consumer payback at the pump.”

Generally, all new fuel-saving technologies come with an added cost. An aluminum vehicle platform on its own costs more than a current platform. However, by reducing the horsepower and torque requirements of the new powertrain and hence cost, the overall costs almost balance out. The increased cost of the aluminum platform is almost balanced out by the decreased cost of the powertrain and other components. For example, a smaller fuel tank is required for the same driving range. The fuel savings gained offsets the additional cost of the platform and powertrain within one to four years.