Porsche is getting ready to launch its first hybrid model since the 1900 Lohner-Porsche Mixte. The Cayenne S Hybrid uses a petrol engine and electric motor, just like its predecessor did, but with considerably more than the Lohner's 15bhp under the bonnet.
The Hybrid uses a supercharged, direct-injection, 3.0-litre V6 engine. This develops 329bhp between 5,500rpm and 7,000rpm while torque is constant between 2,900 and 5,300rpm at 325lb.ft. Petrol power is backed up by a 51bhp electric motor. The Cayenne can run on electric power alone too, a 'sailing' mode allowing cruising at steady speeds of up to 86mph without using any petrol, although Porsche does not say how long electric power can be used at that speed.
To get from standstill to a steady speed the Cayenne Hybrid can call on both petrol and electric power. Porsche claims the hybrid will accelerate from 0 to 62mph in 6.8 seconds - the same as the V8 Cayenne S automatic manages. On paper the Hybrid appears to combine the performance of the petrol-powered Cayenne S with the economy of the
turbodiesel model. The combined cycle fuel consumption is 31mpg while carbon dioxide emissions are 'less than' 210g/km.
By using a hybrid drive system Porsche appears to have reconciled high performance with acceptable fuel economy. We will have to wait for our first drive before we can say for certain how it lives up to the claims. The Cayenne S Hybrid will go on sale in 2010.
John Lambert - 30 Apr 2009