WHEN Porsche first introduced the Cayenne it entered new territory - the luxury large SUV market.

That was seven years ago and amazingly, the big sports 4x4 has become the company's best selling model.

Now, it is blazing another trail as Porsche's first hybrid, with a petrol/electric powertrain almost as fuel efficient as a diesel but with the punch of a V8.

It should have a 150mph top speed and reach 60 from rest in about 6.5 seconds but should be able to average 34.4mpg with CO2 emissions of just 193g/km.

That makes it the leanest and cleanest vehicle the company has ever produced. Power comes from a supercharged three-litre V6 mated to an electric motor with an eight speed automatic gearbox.

Total power is a hefty 380bhp - pure Porsche without a doubt. But not only can it handle off-road work, it can also run with zero emissions on electric power only.

It's clever stuff and should make the hybrid a compelling member of the new Cayenne line up.

As well as a button to select electric drive only, it has internally adjustable suspension and the controls are mounted in a new console between the front seats.

: Lexus RX450h