In the past decade, automobiles in the United States have followed the same trend as Americans' waistlines, growing bigger and bigger. We're not just talking about enormous models such as the Hummer and other full-size SUVs. Even sedans and mid-sized cars have ballooned. For instance, the 2007 Honda Accord outweighs its 1988 counterpart by almost 600 pounds [source: Woodyard].
Since fuel prices have risen as well, car companies and consumers alike are scrambling to find more efficient alternatives. Much of the mainstream attention has focused on different ways to power cars, rather than altering the body. But one promising solution that researchers and manufacturers have tossed around since the mid-1990s is the concept of an ultralight car.
The term started popping up in many places in 1993 with the kick-off of the Partnership for a New Generation of Vehicles. This agreement brokered by then-Vice President Al Gore and the executives of the Big Three auto makers (Ford, DaimlerChrysler and General Motors) laid out a goal to build an 80-mile-per-gallon car by 2003 [source: Partnership for a New Generation of Vehicles]. One cornerstone of the alliance was researching ultralight materials, such as carbon composites and lighter steels and plastics as a way to jolt fuel efficiency.
Just how light are we talking? German car startup company, Loremo, which stands for low resistance mobile, will soon put its first models on sale in Europe that weigh around 1,200 pounds (544 kilograms). To put that in perspective, that 2007 Honda Accord we mentioned earlier is 3,197 pounds (1,450 kilograms). And it's even lighter than the pint-sized, 1800-pound (816-kilogram) Smart Fortwo model. In exchange for the more svelte body, the Loremo LS gets around 120 miles to the gallon [source: Loremo].
Why does weight make such a difference? And how safe are these fitter models? We'll talk ultralight science and safety on the next page.
Size and Safety of Lighter Cars
The average car uses only 15 percent of its energy to actually move the vehicle and drive [source: FuelEconomy.gov]. Most cars on the road today lose all but that sliver of power to braking, friction, idling and having to haul piles of accessories [source: Lovins]. By slightly altering the design, prioritizing function over luxury and using lighter materials, those issues can be minimized. In fact, according to the U.S. Department of Energy, every 10 percent of weight reduction translates to a 7 percent increase in fuel economy.
Thanks to that significant exchange, one of the goals outlined by the Partnership for a New Generation of Vehicles was to reduce the weight of cars by 40 percent, or around 1,200 pounds (554 kilograms). But when thinking about ultralight cars like these, it's important to differentiate between mass and weight. The mass, or size, of ultralight prototypes car companies have revealed aren't smaller than the average compact. Rather, the weight of the materials involved makes the difference.
Cars weigh so much because many of them are made from steel parts and sizeable engines. Ultralight future cars will be made of lightweight products including plastics, aluminum and metal composites and other hybrid materials. By adjusting the weight of the car parts, companies don't have to sacrifice size and can also use smaller engines.
But what about safety? If an ultralight car rams into the side of a building, won't it crumple like a ball of paper? Well, yes, it may crumble, but its impact absorption will protect the people inside. According to the State Department, "carbon-fiber composites can absorb 12 times the energy per kilogram as steel [source: Lovins]." Researchers at MIT also have discovered clay nanotech particles that could be used to make ultralight, yet ultra-strong auto parts [source: Bullis]. By adding these tiny particles to materials, it reinforces them and forms a strengthened network for incredible durability.
For Loremo, addressing safety concerns involved creating an entirely new type of car frame. While most cars are designed to distribute impact around the passenger, the Loremo passes it under them. It does so by using a longer chassis, the frame on which the car sits, that runs along the length of the car to spread the force impact linearly. The company compares it to the same effect as striking a nail [source: Boston]. When hit, the nail doesn't break because its impact is directed along its length rather than at an angle. Also, by keeping the body close to the ground and adding air shafts that funnel air through the bottom of the car, it adds driving stability in the same way as featherweight racecars [source: Boston].
When will consumers start to see these ultralight phenomena on the car lot? The Loremo goes into production in 2010, and depending on its reception, it could set off a domino effect. To learn more about future car technology, cruise on to the links on the next page.
Related HowStuffWorks Articles
More Great Links
- Boston, William. "Driving on the Light Side." TIME International. July 17, 2006. (June 23, 2008) http://www.time.com/time/magazine/article/0,9171,901060717-1211547,00.html
- Bullis, Kevin. "Ulta-Tough Nanotech Materials." MIT Technology Review. Jan. 30, 2007. (June 23, 2008) http://www.technologyreview.com/Nanotech/18121/
- Discovery Channel. " The Body." FutureCar. Feb. 14, 2007.
- Lovins, Amory B. "Reinventing the Wheels: The Automotive Efficiency Revolution." Economic Perspectives. U.S. State Department. July 2006. (June 23, 2008) http://usinfo.state.gov/journals/ites/0706/ijee/lovins.htm
- U.S. Department of Energy. "Lightweight Materials." (June 23, 2008) http://www.fueleconomy.gov/feg/lightweight.shtml
- Woodyard, Chris. "Vehicles keep inching up and putting on pounds." USA Today. July 16, 2007. (June 23, 2008) http://www.usatoday.com/money/autos/2007-07-15-little-big-cars_N.htm
- Zakaria, Fareed. "A Cure for Oil Addicts; Energy's Future: Amory Lovins tells how we can leave the age of gas pumps profitably and painlessly." Newsweek. Aug. 6, 2007.