Frankfurt's first surprise: Audi's Q7 hybrid

The announcement was made at the "set-up" day for the world's biggest motor show, when the big German brands unveil their star cars while most other car-makers are still putting the finishing touches on their stands.

After months of pre-release drip-feed publicity, the official unveiling of the Q7 itself was something of an anti-climax. But the announcement that there'd also be a hybrid Q7 surprised the media throng at the world's biggest motor show.

The hybrid Q7 was unveiled as a "concept study", but Audi officials soon said that the green version of the big SUV - well, greener than the standard 4.2lt V8 Q7, anyway - would likely go into production. On sale date in Europe is expected to be 2008.

Dubbed as the "clean way to high performance", the Q7 hybrid links the 257kW/440Nm FSI direct-injection petrol V8 with an electric motor that adds up to an extra 200Nm of torque and 35kW of power.

Like the regular Q7, power is delivered via Audi's permanent Quattro all-wheel drive through a six-speed tiptronic transmission.

Claimed performance from the hybrid is an impressive 6.8 seconds 0-100km/h - quicker than both the standard Q7 V8's claimed 7.4 seconds and the 3.0lt six-cylinder Q7's 9.1 seconds.

Yet the hybrid is said to deliver around 13 per cent better fuel economy than the standard V8 Q7.

Lift the hybrid's bonnet, and there's no evidence that it's any different from the standard 4.2lt Q7. The electric motor slots in between the engine and the automatic transmission's torque converter. It's hooked up to the V8 via a separating clutch that allows propulsion by either the electric motor, the petrol engine or both acting in unison.

Audi says the set-up doesn't impinge on cabin space, which still offers seating for seven.

The electric motor draws its energy form a battery system housed under the cargo area floor. Also under there is a voltage transducer that supplies power to the vehicle's electrical system. The so-called "tyre mobility system for repairing punctures" is next to the battery compartment.

The electric motor and nickel-metal hydride (NiMH) battery are said to be veritable lightweights compared to earlier generations of hybrid vehicles. The hybrid system adds 140 kilograms - or seven per cent - to the standard V8 Q7's kerb weight.

Don't get too excited about the hybrid heading downunder. The standard Q7 should be unveiled at next month's Sydney motor show but won't go on sale until late 2006. At this stage, Audi Australia isn't saying if the hybrid version will follow a couple of years later.

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