Replacing the A3 Sedan concept's petrol-only 300kW 2.5 litre four-cylinder engine is a turbocharged and direct-injected 157kW 1.4 litre TFSI petrol engine, mated to a 20kW electric motor.
Combined with Audi's seven-speed S tronic automatic transmission, the A3 e-tron concept is capable of a 0-100km/h sprint in 6.8 seconds, on its way to a top speed of 231km/h.
Power for the electric motor is supplied by a 12kWh lithium-ion battery park, and in electric-only mode, the A3 e-tron offers a driving range of up to 54 kilometres.
The unveiling of Audi's latest in a growing line of e-tron concepts follows the reveal last week of the A3 e-tron hatch prototype, based on the current model and featuring an all-electric drivetrain.
The all-new A3 is expected to make its international production debut in the second half of 2012, in both sedan and hatch form.