Oak Ridge National Laboratory recommends automotive aluminium over steel

Opting for aluminum over steel in new automobile construction to improve fuel economy is also the best way to reduce energy consumption and carbon emissions, according to a new study by the United States Department of Energy’s Oak Ridge National Laboratory (ORNL).

“As the U.S. works to reduce dependence on foreign oil, promote clean energy and combat climate change, this report definitively documents why aluminum offers the most promise for cutting total automotive-related carbon emissions and energy use,” said ORNL’s Sujit Das, expert on product lifecycle assessments.

The ORNL study modeled a typical 2012 crossover SUV reflective of the average on-the-road vehicle in the U.S. in terms of weight, performance, fuel economy and materials mix of steel, high-strength steel and aluminum.

Building on an earlier crossover SUV study by the United States Environmental Protection Agency (Light-Duty Vehicle Mass Reduction and Cost Analysis — Midsize Crossover Utility Vehicle, Aug 2012), ORNL researchers analyzed a baseline SUV (a comprehensive mix of mild and high- strength steel), a lightweight steel vehicle (optimized for maximum use of high-strength and advanced high-strength steel), and a lightweight aluminum intensive vehicle (including currently available body, doors, trunk and hood applications).

The ORNL said modeling for this study conforms to internationally recognized standard practices (ISO 14040 and 14044). Comparative data sets used in the study were provided directly to ORNL researchers by the U.S. steel and aluminum industries respectively, both sets of which are current, peer-reviewed and publicly available. The Aluminum Association underwrote the effort.

The ORNL study is consistent with an earlier independent study by the magnesium industry which also concluded that aluminum has the smallest carbon footprint of competing materials when examining total lifecycle CO2 emissions.

Additional benefits of aluminum come from its recycling properties. Recycling aluminum saves 95 percent of the greenhouse gas emissions associated with primary aluminum production, and requires only 5 percent of the energy. Also, nearly 90 percent of automotive aluminum is recovered and recycled and aluminum is infinitely recyclable without degradation to the material.