Audi, in its search for alternatives to conventional propulsion, has finally nailed its colors to a mast--and that mast is plug-in hybrids.

In addition to the A3 Sportback e-tron later this year and plans for a plug-in hybrid version of the A4, the German automaker could develop plug-in hybrid variants of the A6 and A8 sedans and the Q7 SUV, too.

Speaking to Indian Autos Blog, Audi's research and development chief Dr. Ulrich Hackenberg confirmed the plug-in models as a way of meeting future European legislation.

The new Audi Q7, due next year, will be the first of these Audis to tout a new plug-in powertrain, with other set to follow.

It marks quite a departure for the company, which had previously held quite a cautious stance on alternative propulsion and electric drivetrains.

It's said to be one of the reasons previous R&D chief Wolfgang Dürheimer was dismissed from the company, his strategy on alternate powertrains proving too conservative.

Evidence that this is the case is the recent re-confirmation of production for Audi's R8 e-tron electric supercar.

On and off more times than a celebrity marriage, Audi has recently confirmed that the e-tron should hit the streets with much greater range than the concept we drove last year in Berlin.

Developing alternative powertrains is not a cheap process though--heavy investment in alternate technologies and propulsion systems saw Audi's profits fall 7.7 percent last year, despite 8.3 percent greater sales.

In all, the company is investing nearly 30 billion dollars from now until 2018 in new products, with plug-in vehicles featuring heavily in future line-ups.

The A3 Sportback e-tron uses a 1.4-liter turbocharged gasoline engine and electric motor combination with 204 horsepower, providing brisk performance.

Larger models are likely to use a slightly different setup, perhaps similar to the 3-liter V-6 plug-in hybrid system used in the Porsche Panamera S E-Hybrid--VW-owned Porsche shares many of its engines with other companies in the Volkswagen group.

What's certain is that Audi's plug-ins will focus as much on enhancing performance as they do efficiency--the company is keen to keep its prestige image as it moves to plug-in vehicles.


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