Hybrids are rapidly shaping up to be the hot topic among luxury carmakers at the 2010 Geneva Motor Show, but not in the way you might expect. Porsche is dabbling in ultra-high-performance hybrids, and Audi is entering the game with the 2012 A8 sedan, a luxury executive limo with performance and green cred.

It's set to be available from late 2011, promising CO2 emissions of 231.75 grams per mile, which Audi claims will make it the greenest in its full-size class. “We regard the full hybrid as we know it today primarily as a very specific technology for reducing fuel consumption. In due course plug-in hybrids will demonstrate their strong points when drivers expect to cover longer distances in the pure electric mode, in combination with a conventional engine,” says Michael Dick, member of the board of management for technical development at Audi.

Power comes from a 2.0-liter TFSI engine paired with an electric motor to deliver a combined output of 245 horsepower and 354 pound-feet of torque. Audi says this delivers the same performance as the six-cylinder A8, while managing a solid 38 mpg. Either the 45-horsepower electric motor or the 211-horsepower four-pot can propel the A8 Hybrid design study separately or together, making it a "full hybrid." Pure electric mode is good for up to 40.4 mph, and up to 1.2 miles, making it somewhat analogous to Lexus' LS 600h drive system, though at a much smaller and more efficient power/fuel consumption point.

Audi's new hybrid plans are set to lay alongside its upcoming line of e-tron electric vehicles, which will also see a world premiere at Geneva in the form of the Audi A1 e-tron design study.