Lotus has taken the minimalist approach with their Elise model. Some of the principles of hyper car theory can be found here.

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Hypercars on the Road

Several companies have produced hypercars, though most of them are concepts or test vehicles. There really is no strict definition of hypercar -- it simply means a car designed to be very efficient, generally several orders of magnitude better than your average showroom car. The best hybrids available in 2008 can achieve mpg ratings in the 40s (km/h ratings in the 70s) under optimal conditions, which is excellent, but not quite hypercar material.

Interestingly, some companies have been practicing hypercar theory for decades, although they haven't taken it to the extremes necessary to achieve 100 mpg (160.93 km/l) or more. Lotus is a British company known for its lightweight, agile high-performance cars like the Elise. Their design philosophy involves stripping away anything unnecessary to keep weight minimal. This gives the Elise excellent handling and amazing acceleration, even with a four-cylinder engine. Smart Cars incorporate hypercar principles as well, with a small, light design intended to carry people in urban areas.

The Rocky Mountain Institute developed a hypercar they call the Hypercar Revolution. Its design is similar to the hypothetical hypercar we designed on the previous page. The RMI Hypercar is a small SUV/crossover that seats five adults and can tow a half ton up a steep slope, but it's an ultralite vehicle.

Volkswagen built and tested a hypercar called the L1 in 2002. It's a radical design that's shaped like the cockpit of a fighter jet. There's room for the driver and one passenger seated directly behind the driver, plus a little cargo. The hatch swings open sideways, and the interior, while tight, appears to be comfortable. The L1 is powered by a one-cylinder diesel engine and can drive for 100 kilometers (62.14 miles) on a single liter (0.26 gallons) of fuel -- hence the name [source: Wheelspin].

General Motors and Scaled Composites created the Ultralite, a technology demonstration car made of carbon fiber and plastic. It proved that such designs were possible by a U.S. automaker, but GM has not put any hypercars into production [source: Scaled Composites]. Daihatsu and Honda also have hypercar development programs that have resulted in several concept designs, but nothing has showed up at the local dealership yet.

Nevertheless, energy costs worldwide are putting pressure on automakers to offer increasingly efficient vehicles. If carbon fiber construction comes down in price, we could be seeing ultralight hypercars on the road within the next few years.

For more information about hypercars, lightweight automotive technologies and other related topics, follow the links on the next page.