The concept features a prototype hybrid system that drives the front wheels with a 1.4-liter, direct-injection, turbocharged in-line four enginemaking 140 horsepower. The rear wheels are powered by an electric drive system making 41 hp and 148 lb-ft of torque, creating a unique, all-wheel-drive Quattro. The result is a drivetrain that delivers 48 mpg.
The car can be driven just on the rear wheels after the battery is reharged, either by plugging it in to an electric outlet, or by the gas engine. The gas engine takes over when the battery is drained.
Source: Business Week