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What would you pay for a car that gets 100 mpg?

$20,000?

$50,000?

How about $1,000,000,000?

Rep. Dan Lungren, R-Calif., has introduced a bill in Congress offering a billion-dollar prize to the first automaker that builds and sells 60,000 mid-size cars capable of delivering 100 mpg.

The so-called “E-Prize Act of 2012” (H.R. 3872) is modeled after government-backed innovation incentive contests like the DARPA Grand Challenge, which paid million-dollar prizes to private entities for successfully creating fully-autonomous vehicles, with an eye on developing the technology for use by the military.

The program proposed by Lungren’s bill would be run by the Department of Energy as an alternative to current schemes that offer up-front matching funds and loans to automakers to develop high-mileage cars based on speculative sales projections, rather than proven success in the marketplace.

But there’s a catch.

While the Nissan Leaf battery-powered car is already rated at the equivalent of 99 mpg, Lungren’s bill requires that the car that claims the prize runs on gasoline and is built by a company incorporated in the United States. This would apparently also disqualify plug-in hybrids like the Chevy Volt and upcoming Ford Fusion Energi.

No U.S. automaker is known to be close to producing a car that would qualify for the E-Prize as proposed, but Virginia-based startup Edison2 recently won the similar, privately-funded $5 million Progressive Insurance Automotive X-Prize with its 102.5 mpg Very Light Car.

Although not quite a mid-size car in its existing form, Edison2 says it plans to develop the ultra-aerodynamic 830-pound four-seat prototype for production and hopes to license its technology to an established manufacturer.

Anyone out there willing to make a $1 billion bet?

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