Auto X Prize Points to Super-Fuel-Efficient Future

After weeks of grueling on- and off-track testing, the winning vehicles for a share of the $10 million Progressive Insurance Automotive X Prize were announced today at an event in Washington, D.C.

Edison2, a company from Virginia, won the four-seater "mainstream" class of the contest and half of the purse for its aptly named Very Light Car – a gentle push with one's fingertips can get its 830 pounds (363 kilograms) into motion.

Meanwhile, Switzerland's X-Tracer team took down half of the alternative class in the "tandem" two-seater division for its motorcycle-like E-Tracer. The team will accordingly collect a check for $2.5 million.

The remaining $2.5 million went to the winner of the alternative "side-by-side" class, a futuristic buggy dubbed the Wave II from North Carolina's Li-ion Motors.

Some 111 teams originally entered 136 vehicles into the contest. Through three stages of judging and performance tests this summer, this figure was whittled down to just nine vehicles by late July. A final validation stage in national laboratories that began last month then determined the top performances and the ultimate winners.

All entrants competed to achieve one hundred miles (161 kilometers) per gallon of gasoline or the energy equivalent (MPGe) from alternative fuel sources, such as electricity from a battery or hydrogen.

The ethanol-powered Very Light Car achieved 102.5 MPGe, while the battery-powered E-Tracer and the Wave II racked up 205.3 and 187 MPGe, respectively.

Such efficiencies at least double that of the thriftiest, widely available vehicle on United States' roads, the hybrid Toyota Prius, which boasts a 51 miles per gallon (82 kilometers) city rating, according to FuelEconomy.gov.

Besides offering super fuel efficiency, the vehicles had to hold up in safety and roadworthiness tests that were part of the Auto X Prize's overall goal to produce street-legal vehicles with commercial appeal. (The Wave II, for instance, is already available for around $40,000.)

"We've seen a shift in the market since we first launched this competition [in 2007], and a greater awareness by people everywhere to think more seriously about the actions we take, and how they affect our environment," said Peter Diamandis, chairman and CEO of the organizing X Prize Foundation in a statement.

"Gas mileage ranks as one of our top concerns when purchasing a new vehicle and I believe strongly that the innovations showcased throughout the life of this competition will continue to impact and improve our car buying options for the future," Diamandis said.

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Adam Hadhazy is a contributing writer for Live Science and Space.com. He often writes about physics, psychology, animal behavior and story topics in general that explore the blurring line between today's science fiction and tomorrow's science fact. Adam has a Master of Arts degree from the Arthur L. Carter Journalism Institute at New York University and a Bachelor of Arts degree from Boston College. When not squeezing in reruns of Star Trek, Adam likes hurling a Frisbee or dining on spicy food. You can check out more of his work at www.adamhadhazy.com.