Light, Large Efficient Vehicles

February 9, 2003 – Vol.7 No.46

LIGHT, LARGE, EFFICIENT VEHICLES.

The common misperception among consumers here in the U.S. seems to be that to make vehicles lighter - and thus more fuel efficient - they must be smaller. People seem to believe that light must only mean small and believe small vehicles are unsafe on roadways shared with much larger ones. Thus people have a tendency to gravitate to larger vehicles - such as SUV’s - in automobile showrooms. In a just-released poll by Kelly Blue Book, more than 50 percent of respondents rated SUV’s high in safety, despite deep concerns about rollovers.

But vehicles can be large AND much lighter. It just depends on what they are made of. A move away from metals such as heavy cast iron and steel, and a move to more light-but-strong materials such as aluminum, plastics, composites and now magnesium in vehicles, could go along way toward much higher fuel efficiency. According to the Aluminum Association, each 10 percent reduction in the weight of a vehicle results in an 8 percent improvement in fuel economy.

And vehicles built with alternative materials can be safe. The Association also points out that the Audi A8, which is made mostly of aluminum, achieved the best crash test rating offered by the U.S. government. (It’s not overly fuel efficient, though, as it is built for high performance.)

Naturally, the Aluminum Association would like to see more aluminum replace steel in cars, trucks and other vehicles.

CSIRO (the Commonwealth Scientific and Industrial Research Organization) of Australia, through its Elaborately Transformed Metals group, has developed a new magnesium alloy known as AMC-SC1 that could be used for castings to make light-weight engine blocks. CSIRO has also developed a low-cost, magnesium sheet metal that is ready for production use.

The alloy is already being tested as the engine block of a three-cylinder diesel, the Genios LE, built by AVL List. The sheet magnesium can be used for vehicle body panels and other vehicle parts as well as other uses. (Apple Computer, for instance, uses a magnesium frame in one of its laptop computers to keep weight down.) Magnesium can also be used in batteries, according to CSIRO. (Greenvolt, of Canada, produces a metal-air fuel cell that uses replaceable magnesium anodes to generate electric current.)

CSIRO has apparently solved the corrosion (read oxidation) problems associated with magnesium and believes that the alloy, which is about a third lighter than aluminum, could quickly be brought to the production line.

CSIRO is also a founding member of the Global Research Alliance (GRA) formed to pool knowledge from a number of the prestigious research organizations to help solve some of the world’s most pressing problems, including energy and transportation. Visit CSIRO at http://www.csiro.au/ , the Aluminum Association at http://www.autoaluminum.org/ , AVL List at http://www.avl.com/ (click Powertrain Engineering), Greenvolt at http://www.greenvolt.com/, the GRA at http://www.research-alliance.net/ and Kelly Blue Book at http://www.kbb.com/ (click About Us, Media Center, Recent Releases).