ENGINEERING

Lightening the Load

See allHide authors and affiliations

Science  02 Mar 2012:
Vol. 335, Issue 6072, pp. 1020
DOI: 10.1126/science.335.6072.1020-c
CREDIT: ISTOCKPHOTO.COM

One clear-cut method of raising the fuel efficiency of a car is to reduce its weight. Of course, that's easier said than done, given competing constraints such as safety and performance. Alonso et al. focus on a more subtle aspect of the problem. In principle, an overall reduction in gross vehicle mass (GVM) enables an associated reduction in the masses of many individual components that now bear and act on a lighter load. In practice, such secondary mass savings (SMS) may go unrealized because the subsystems are designed and manufactured separately—and in some cases are used in a range of car models that vary in GVM. The authors therefore empirically analyze the subsystems in a set of 77 vehicles (representing 13 different manufacturers) currently marketed in North America and Europe to pinpoint sources and scope of SMS, with the ultimate goal of facilitating consideration of these factors earlier in the overall design process. Their statistics indicate prospective mean SMS as high as 0.95 kg per kg of primary mass reduction.

Environ. Sci. Technol. 46, 10.1021/es202938m (2012).

Navigate This Article