The 2008 Paris Motor Show will play host to a new variation on the theme of a more compact Audi - the five-door A1 Sportback concept study - which combines cutting-edge styling with optimum economy of space, supreme quality and a series of visionary technical solutions that help to reduce CO2 emissions to just 92 g/km. The 3.99-metre long and 1.75-metre wide study furthers the many advances made by the three-door A1 project quattro show car which debuted in Tokyo in 2007.
A new version of the innovative hybrid technology employed in the A1 project quattro provides power for the A1 Sportback concept. Under the bonnet is a transversely mounted 1.4-litre TFSI engine developing 150PS and 240Nm, and directing this to the front wheels by means of the S tronic dual-clutch transmission. A 20 kW (27 hp) electric motor integrated in the drive train is able to deliver up to an additional 150 Nm of torque (110.63 lb-ft) when the vehicle is accelerating.
During the boosting phase, i.e. when the TFSI engine and electric motor operate simultaneously, the two power packs deliver impressive propulsion. The tried-and-tested front-wheel drive configuration - supplemented by the newly developed, ESP-controlled active front differential lock - ensures optimum power transfer to the road.
The electric motor is also capable of powering the vehicle unaided for zero-emission driving in residential areas, for instance. The capacity of the lithium-ion batteries gives the vehicle a range of up to 62.14 miles in pure electric mode; the motor can be recharged from any power socket. The automatic start/stop facility, energy regeneration and phases of purely electrical operation reduce the fuel consumption and emissions of the Audi A1 Sportback concept by almost 30 percent compared to when it is running on the combustion engine alone. Despite its strong performance, with acceleration of 0 to 62mph in 7.9 seconds and a top speed of 124mph, the Audi A1 Sportback concept is nevertheless capable of returning up to 72.4mpg; CO2 emissions are an efficient 92 g/km.
Regenerative braking
Over run, or the so-called regeneration phase, is one of the most important elements of this vehicle concept for optimizing efficiency as it transforms the braking energy released during deceleration phases back into electrical energy, instead of it being wasted and released as heat.
Power transmission to the front wheels is the task of the Audi S tronic dual-clutch gearbox. It allows the driver to change gear in fractions of a second without the use of a clutch pedal and with no interruption to the power flow. If required, the transmission performs the gear changes fully automatically, too. If the driver wishes to change gear manually, he or she can do so by using the shift paddles mounted on the steering wheel. Reverse gear and neutral are engaged via the gear knob on the centre console. The park position is automatically selected when the electric parking brake is engaged.
Advanced chassis with new active differential lock
The fundamental ingredient for outstanding driving safety and handling dynamics is supplied by the sophisticated chassis design, comprising McPherson front suspension and four-link independent rear suspension. Large 18-inch wheels with 225/35 R18 tires boost both driving pleasure and safety. Thanks to the newly developed active, ESP-controlled front differential lock, propulsive torque is distributed according to the driving situation, thereby achieving enhanced steering precision and directional stability as well as improved traction and handling when cornering.