Yesterday we reported Audi is considering boosting production numbers for its upcoming A1 minicar to more than 120,000 to satisfy rising demand for premium small cars both in the U.S. and Europe as well as help reach its overall goal of selling 1.5 million vehicles by 2015. To make selling all of those A1s possible, we have new details that Audi is planning a number of different variants including a new three-door Sportback model.

Another important reason for the new minicar family is to help Audi increase the number of low CO2 models it sells. Unlike their French and Italian counterparts, who specialize in compact and efficient hatchbacks, German carmakers are mostly recognized for building big and thirsty luxury cars. Thus it’s the German labels that will be finding it the hardest to meet Europe’s new carbon emissions regulations set to roll in by 2012.

We’ve already covered news of the A1 four-door and cabrio models but Audi is tipped to launch this new Sportback version as well. This new rendering give us an accurate look as to what to expect, revealing designers will be sticking to the lines of the A1 Metroproject concept car. Distinct features are the car’s short wheelbase and arching roof. The Sportback is likely to receive more premium features than the rest of the A1 fleet including sporty bodykits and larger 17in wheels.

Like the rest of the range, the new Sportback will likely feature a series of low capacity TSI and TDI units ranging from 1.4 to 2.0L, plus a possible mild hybrid model could also be offered. The design will use a small electric motor integrated into the drivetrain, which kicks in during high-load situations.

2011 Audi A1 variants