The Disputed Cost of Light, Strong Cars

Rocky Mountain's Lovins touts advanced materials, but automakers aren't buying it.

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Is carbon fiber one of the answers to stopping global warming and ending our oil dependence? Energy efficiency guru Amory Lovins thinks so, but the automakers—so far—do not.

Lovins, founder of the Rocky Mountain Institute, both made his point and got a laugh at the National Academy of Sciences energy summit last week by covering his head briefly with a "carbon cap." It wasn't a "cap" on carbon dioxide emissions like in the Kyoto protocol or the Warner-Lieberman bill, but it would be relevant to one. The headwear was a hard, black 2-millimeter-thick test piece for a military helmet. Lovins took the hat off and then whacked it to demonstrate its ringing clang. "You can tell that plastics have changed since The Graduate," he said.

In fact, Lovins has long argued that carmakers could dramatically improve their fuel efficiency by cutting down the weight of their vehicles radically by switching from steel to advanced light materials, which include carbon fiber and thermal plastics. A study the Rocky Mountain Institute conducted with Pentagon funding and released in 2004, "Winning the Oil End Game," concluded that advanced light materials could cut vehicle weight in half and boost efficiency to 85 mpg for a midsize car or 66 mpg for a midsize sport utility vehicle.

Lovins also argues that "lightweighting" (as opposed to simply making steel cars smaller) would boost vehicle safety because the advanced materials can absorb up to 12 times as much crash energy per pound as steel.

But just as Lovins was touting the virtues of carbon fiber to some of the nation's energy scientists, Automotive News last week was quoting the carmakers, who say it can't be done. "Lightweight materials are horrendously expensive, General Motors Vice Chairman Bob Lutz told the trade publication. "People keep forgetting the cost equation. By the way, in a recent interview with my colleague Rick Newman, Lutz also dismissed advanced materials and seemed more excited about advanced biofuels, a solution that would shift the burden of the oil problem off the backs of the carmakers.

Helmut Weixner, Hyundai's European head of engineering design, told Automotive News that it tries to use lightweight materials sparingly and instead seeks "a lot of small points where you can have an impact." He said: "You don't want to make a full vehicle in a polycarbonate. It's too expensive.

But Lovins would argue that the carmakers are thinking too small. He says his researchers have shown how advanced materials would allow the automakers to eliminate the body shop and paint shop and assemble cars with far fewer pieces and a radically scaled-back powertrain. "The cost of your materials is paid for by simpler automaking and a three times smaller car train," he contends.

Lovins says there are signs that the automakers are catching on. For example, Nissan says it's aiming for a 15 percent average weight reduction in all its vehicles by 2015. And Toyota's 1/X concept car, shown at the 2008 Chicago Auto Show last month, has the same interior space as a Prius but weighs only 926 pounds—about one third the weight—with an aim of doubling the hybrid's already high efficiency.

"I'd say lightweighting is the hottest strategic trend in the industry right now," Lovins said.

But Toyota's 1/X is like all concept cars: It's not on sale, and the price is not known to the public. Toyota says it's "a glimpse into the next era of automotive technological design." Lovins was talking about ultralight materials as long ago as 1998. That next era sure is taking a long time to arrive.