Lotus is synonymous with lightweight sports cars and Lotus Engineering has released a study showing how weight savings can be applied to mainstream vehicles. Taking a Toyota Venza crossover (sold in North America), it demonstrated a 38 percent mass reduction (excluding powertrain) for just a three percent increase in component cost.
The Venza was stripped down and analysed in detail to see where savings could be made. Two weight saving studies were conducted, a 'near term' version using existing manufacturing technologies along with improved materials and component integration; and one that uses more advanced construction techniques.
According to the study the former approach not only netted a 21 percent weight reduction but a two percent cost saving. Compared to the standard car the structure used more high-strength steel and much less mild steel and iron.
The more radical approach involved increased use of composites, aluminium and new joining processes such as adhesive bonding. This yielded the greater, 38 percent drop in weight. In both cases the objective was to achieve the saving without compromising space, comfort or refinement.
The main benefit of saving weight is reduced fuel consumption and lower emissions. The U.S. Department of energy estimates that a 33 percent weight reduction gives a 23 percent improvement in fuel consumption. With ever increasing pressure to reduce CO2 emissions Lotus' weight saving techniques are bound to attract plenty of interest.
John Lambert - 28 Apr 2010