Road Test: Volkswagen Touareg 3.0 V6 TSI Hybrid 5dr Tip Auto

You might have worked out from the not-so-subtle stickers that this is Volkswagen's new hybrid Touareg. What you won't know is that this supercharged V6 - electric hybrid is also part-2010 Porsche Cayenne and, probably, Panamera too.

See, the Touareg part of this test car is mostly irrelevant - a mule to carry essentially production-ready prototype hybrid kit developed with Porsche for introduction next year. And it's important tech, not least to tempt the diesel-shy US premium market as it continues to wake up to greener life.

Over here, we'll look at it slightly differently. The system uses the engine from the Audi S4 and combines hybrid tech to deliver 369bhp, so for us it's about performance and towing ability - plus, perhaps, a bit of eco spin for the marketing boys.

That performance bias is evident in the set-up. VW chose to develop an eight-speed automatic transmission, rather than go down the CVT route adopted by Toyota - and the system immediately feels more responsive as a result. It also means the Touareg retains its off-road ability and massive 3.5-ton towing capacity.

The gearbox is separated from the supercharged V6 engine by an electric motor which both charges and takes power from a battery that sits in the spare-wheel well. It all operates in familiar hybrid fashion - the car will run on battery alone up to 30mph for a mile or so, unless you demand more than a feather of the throttle. After that, petrol and electric work together to give you maximum grunt.

And when you floor it, the system really delivers. The test car will hit 62mph in 6.8 seconds and, if anything, it feels faster than the numbers suggest. Top speed is 148mph.

There's a special clutch, though, which lets the engine cut out if you lift off the gas at any speed below 90mph. This'll help hit the emissions target of less than 210g/km and claimed fuel consumption of 31mpg - both good for an SUV and better than most diesel rivals, including existing Touareg models and BMW's X5. All eyes are on the new Lexus RX450h, though, which won't be in the same performance ballpark as this system but promises 150g/km CO2.

The hybrid system works smoothly, even if you try to trip it up - the engine cuts in and out with minimal fuss, if not quite as smoothly as the Lexus system. VW reckons it costs about £4k to build, so expect that premium when it's on sale in 2010.

Good news, then, for power-hungry 4x4 buyers with a conscience. But until the system is used on smaller cars, it won't be saving any polar bears.