Sustainability throughout in new 'i' cars

Updated: 2012-04-23 07:55

By China Daily and Agencies (China Daily)

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Sustainability throughout in new 'i' cars

BMW i8 Spyder concept vehicle is making its global premiere in Beijing.

Sustainability throughout in new 'i' cars

Sustainability throughout in new 'i' cars

'Miracle' carbon fiber, electric power combine for high performance and energy conservation

Remember this exchange in The Graduate starring Dustin Hoffman as Benjamin?

McGuire: "I just want to say one word to you. Just one word."

Benjamin Braddock: "Yes, sir."

McGuire: "Are you listening?"

Benjamin: "Yes, I am."

McGuire: "Plastics."

If Ben were to get advice from McGuire today about a new field to stake his future on, the answer could well be "carbon fiber."

Carbon fiber is a key material for the mobility of tomorrow and will change the landscape of the industry, which BMW is demonstrating with two futuristic models, the i3 and i8, debuting this week in China at the Auto China 2012 show in Beijing.

The miracle material, just two-thirds the weight of steel but five times its strength, will dramatically improve fuel economy by shaving hundreds of kilograms off the weight of a car.

The i3, with an electric motor powered by lithium-ion batteries, will weigh just 1,250 kilograms - about 20 percent less than a Nissan Leaf. The i8, with both gas and electric motors, will be faster than a Ferrari and still be capable of 32 kilometers per electric charge and consume just 4.7 liters of gasoline per 100 kilometers. BMW will launch the two models next year.

Carbon fiber has found its way into fishing rods and tennis rackets, and in larger quantities into airplanes like the Boeing 787 Dreamliner and the bodies of Formula One racecars. Some high-end performance cars like the BMW M6 have a carbon fiber roof and body panels, and the material is used for interior trim in the place of wood veneers or aluminum.

"Looking forward, carbon fiber is not just a material for small-scale use but a key lightweight technology with revolutionary impact on automobile design in future," said Nan Chen, a senior Chinese auto industry commentator.

So far, high-volume applications have eluded carbon fibers due to the high cost. According to published estimates, carbon fiber costs more than $20 per kilogram, much cheaper than the $300 a kilogram it cost a decade ago, but is still about 10 times more expensive than steel. The construction process is also laborious.

How it is built

That has not deterred BMW, which has invested $100 million to build a carbon fiber factory in the United States, 290 kilometers east of Seattle, Washington. The factory is co-owned and operated by a German company, SGL Carbon SE.

Norbert Reithofer, chairman of BMW AG, made it clear that the Bavarian auto giant wants to be a pioneer and driving force in the industry's technological transformation through both "evolution and revolution".

"The further development of high-efficiency combustion engines and hybrid drives - this is what we consider evolution. Zero-emission mobility, combined with production and the innovative use of materials and new services - this is what we call revolution," Reithofer said last month at the group's annual accounts press conference.

The production chain is truly global.

Here is what goes into the composites SGL makes for BMW:

Colorless precursor fibers come from a joint venture with Mitsubishi Rayon in Japan. In a 200 meter-long plant in Moses Lake, Washington, the fibers are pulled over hundreds of reels and baked at temperatures as high as 1,400 C.

That evaporates all elements except carbon atoms, which remain neatly arranged to give the fibers both their black color and unique strength.

What is left over are filaments one-tenth the width of a human hair. When about 50,000 of them are bundled into a thin thread for further processing, they can lift almost a ton in weight.

The threads are shipped to Wackersdorf in southern Germany where they are woven into mats in a plant twice the size of an American football field.

At another site about 110 kilometers south in the town of Landshut, the mats are cut and layered into moulds, put under a vacuum and immersed in a plastic resin. Cured at about 100 degrees C, it hardens within minutes to create three-dimensional car body parts that are harder and more rigid than steel at half the weight.

From here they travel to BMW's Leipzig Germany plant to be assembled.

The use of carbon fiber materials now seems to have become one of the hottest trends in the car industry's drive to lower its carbon dioxide emissions.

Other German automakers are following BMW's trail. Volkswagen, maker of Audi, has bought a 9.9 percent stake in the SGL venture.

More than electric

To BMW, the i models are not just about being electric. It embodies the German carmaker's vision of future mobility, with the concept of sustainability, environmental awareness and energy efficiency throughout the chain of business from oil well to wheels on the road.

Production at the SGL joint venture Moses Lake carbon fiber plant is using electricity generated entirely from hydroelectric power.

Compared to the already efficient BMW Group production network, the production plant for BMW i vehicles in Leipzig will save an additional 70 percent on water consumption and 50 percent on energy for each vehicle produced.

More than 80 percent of the aluminum used in the i3 is produced either using renewable energy or from secondary material. Aluminum produced from 100 percent renewable material - known as secondary aluminum - can reduce CO2 emissions by 50 to 80 percent compared to conventional manufacturing.

"We see more and more customers that have the clear wish for premium mobility and absolute sustainability, and this is exactly what we want to give them with the BMW i - either the i3 or the i8. Sustainability starts right after the development process and goes to the suppliers, to the BMW production and of course afterwards to the usage of the car, until it comes to the end of the resulting process," said Klaus Draeger, BMW's board member and chief of research and development.

Yet to Adrian van Hooydonk, BMW's chief of design, even a highly technical, energy-efficient car can still evoke desire.

"Both from the drive train technology, the body and everything that has to do with this brand is new. It is a clean-sheet approach," he said.

"So for a designer it means you are completely free. And I think we've used this freedom. We want to draw attention that this new mobility is there and that it will be emotionally attractive, emotionally appealing, and not just on the rational side."

Sustainability throughout in new 'i' cars

BMW i3 concept vehicle

Sustainability throughout in new 'i' cars

Carbon fiber: Key material for the mobility of tomorrow

Sustainability throughout in new 'i' cars

BMW Vision EfficientDynamics concept vehicle stars in Mission Impossible 4.