What is it?
This is Audi's first production hybrid car and it will go on sale across the world 'during 2011'.
Under the otherwise unchanged exterior of this pre-production machine, the Q5's running gear has been substantially re-engineered.
An electric motor is fitted between the engine and the eight-speed Tiptronic transmission. Audi has dropped the transmission's torque converter and replaced it with a multiplate clutch operating in an oil bath. This clutch pack couples and de-couples the engine and electric motor. The Q5's engine is Audi's familiar 2.0-litre turbocharged, direct-injection petrol unit. It has also been modified for hybrid operation.
Ancillaries such as the air-con system are now driven by electric motors rather than mechanical drive belts. It does without a starter motor, using the electric motor to spin into life.
The power electronics module, which switches the battery's direct current to alternating current for the motor, sits on top of the engine. At the rear of the car, a slim battery pack (a modest 1.3kWh, 38kg in weight and capable of powering the car for 1.9 miles at 38mph) has been fitted above the rear axle. To add to the complexity, this battery, the power electronics and motor all require their own cooling circuits.
What's it like?
Audi says the Q5 offers five different running modes and the driver can also select three running modes.
EV, which prioritises battery-only running in the city, 'D' which switches between the engine and motor for maximum range and 'S' mode for the full 354 lb ft torque from both motors. The key to a successful parallel hybrid drivetrain is a seamless integration between the engine and electric motor, because the software will swap frequently and quickly between the two power sources.
Sadly, the Q5 test car suffered from occasional, but noticeable, transmission shunt as the engine was cutting in after an electric-only start.