Audi will concentrate heavily on the development of plug-in hybrids over the next few years, as the company plans to offer a plug-in model of very significant model in its lineup by 2020.
Speaking to Autocar, Audi's research and development chief Ulrich Hackenberg says plug-in hybrids will be prioritized over other plug-ins, as they best meet Audi's customers' expectations.
Future plug-in Audis will be based off two main hybrid powertrain families, according to Hackenberg.
The first will be based around the 1.4-liter TSI gasoline engine and electric motor setup used in the A3 Sportback e-tron.
The A3 sits on Audi and Volkswagen's MQB platform, which underpins all of the group's compact models--from the Volkswagen Golf through the A3, to the new Audi TT coupe.
While the A3 e-tron and its Volkswagen Golf GTE cousin are both front-wheel drive--developing 204 horsepower through a six-speed 'e-S tronic' dual-clutch transmission--four-wheel drive models could make an appearance. These would use an additional electric motor mounted at the rear axle.
The second plug-in line would be based on Audi's larger MLB-Evo platform.
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These vehicles, including cars like the A6 and A7, use a longitudinally-arranged engine and transmission, between which an electric motor is mounted. Audi's famous quattro system could also be used here, either electronically or mechanically.
Audi has already announced its plans for a plug-in hybrid version of the next-generation A4 sedan, as well as plug-in versions of the A6, A8 and Q7 SUV.
A plug-in hybrid version of the smaller A1 subcompact, sold in Europe, would likely differ from the existing A1 e-tron concept though--Hackenberg wasn't a fan.
The development boss said that any range-extending engine powerful enough to recharge the batteries "might as well be driving the wheels".
The company hasn't mentioned further plug-in models, but given the MQB platform's adaptability and Hackenberg's announcement that all key models would be catered for, we might even see a plug-in TT somewhere down the line.