Energy Tradeoffs in Automotive Use of Steel, Fiber-Reinforced Plastics and Aluminum

The embodied energy, structural weight, and transportation energy (fuel requirement) characteristics of steel, fiber-reinforced plastics, and aluminum were assessed to determine the overall energy savings of materials substitution in automobiles. In body panels, a 1.0-lb steel component with an associated 0.5 lb in secondary weight is structurally equivalent to a 0.6-lb fiber-reinforced plastic component with 0.3 lb in associated secondary weight or a 0.5-lb aluminum component with 0.25 lb of secondary weight. The total energy requirements of structurally equivalent body panels (including their embodied and life cycle transportation energies) are: steel (211.6 × 10³ Btu), fiber-reinforced plastics (126.7 × 10³ Btu), and aluminum (174.3 × 10³ Btu). Fiber-reinforced plastics offer greatest improvements in embodied and total energy requirements, while aluminum achieves greatest savings in transportation energy.