What is it?
This is the Volkswagen Touareg hybrid. It’s Volkswagen’s first real go at petrol-electric hybrid drive, although it will a while before you can buy a Touareg hybrid. This drivetrain - a 323bhp petrol V6 from Audi and an eight-speed automatic - won’t feature in the current Touareg, but will be launched in the next-generation model, due in 2010.
In the VW Touareg hybrid there’s a 38kw (51bhp) motor powered by a nickel-metal hydride battery pack mounted underneath the boot in the space usually reserved for the spare tyre.
The layout of the VW Touareg hybrid, known as a parallel system, is familiar, having already appeared in a number of hybrids. But by employing a disengagement clutch, the VW Touareg hybrid has overcome one major drawback, namely that the petrol engine and electric motor are always connected.
In some hybrids the crankshaft and pistons within the petrol engine continue to operate even during electric-only propulsion. This adds to wear and also zaps overall efficiency.
The VW Touareg hybrid uses the disengagement clutch to ensure the petrol engine is shut down completely when the electric engine is in use.
What’s it like?
The VW Touareg hybrid’s electric motor is terrifically refined, providing almost seamless operation in the city, with impressive levels of performance and the sort of fuel economy to make diesel lovers turn green with envy. Still, it does take some getting used to before you feel totally comfortable behind the wheel.
When you crank the key, the petrol engine doesn’t fire up unless the batteries are low on energy or, as we discovered on occasion in a freezing Wolfsburg, it is extremely cold. Instead, the Touareg hybrid wafts away solely on electric power.
The electric motor is powerful enough to provide the sole mode of propulsion for the Touareg hybrid up to 30mph. Yet when the engine kicks in the changeover is barely perceptible.
It’s quick too - 62mph comes in a claimed in 6.8sec, 0.7sec faster than the 4.2-litre V8 Touareg.
More impressive are the increases in economy and consequent reduction in emissions. Combined economy is 31.4mpg, 3mpg better than the V6 diesel Touareg, while the CO2 rating is 210g/km.
The hybrid drive system adds around 175kg to the kerb weight of the Touareg, so there’s a new, lighter four-wheel drive system which replaces the multi-plate clutch with a version of Audi’s Torsen differential.
Other drawbacks? By employing a disengagement clutch, The VW Touareg hybrid is to use its petrol engine to charge the batteries while the car is running on electric power.
Should I buy one?
There’s no doubt that hybrid drive greatly extends the appeal of the Touareg, providing it with performance and green credentials, so it’s a shame that you won’t be able to get the VW Touareg hybrid until the second-generation model arrives in 2010.
Still, that at least gives VW’s engineers time to further improve what is already one of the most effective combinations of petrol and electric propulsion yet devised.