The paper investigates the influence of selection of materials on the total energy consumption of a personal vehicle and explores whether energy is conserved by providing longer service lives. Energy consumption over a 300,000 km period is scrutinized under separate categories of vehicle manufacture, operation, maintenance and repair, and final disposal. Four different groups, classified in terms of service life, weight, and choice of construction materials, were studied on the basis of data from government-subsidized studies; the effect of weight on energy consumption was identified by two evaluation factors.Results showed that vehicles with long service lives are energy-efficient, and lightweight vehicles are particularly so. However, the affect of weight on energy consumption was not as strong as previously thought. The investigation suggested ways of reducing total energy consumption by 2 to 20% (e.g., extended service lives, extensive use of aluminum).