Porsche's Cayenne Hybrid, which will share underpinnings with the new Panamera four-door coupe, is now expected as a 2010 model at the earliest. It will be a typical full hybrid with the electric motor sandwiched between the gasoline engine and transmission. We expect a 3.6-liter narrow-angle V-6 will be paired with trunk-mounted lithium-ion batteries. Electrics will be used for electro-hydraulic power steering, vacuum pump (brakes and climate control), and air-conditioning, all under the auspices of a controller that runs 20,000 data parameters--more than three times what gasoline Cayenne controllers do.
Porsche is aiming at a 24-26-mpg city rating which seems realistic given the 6.0-liter Tahoe Hybrid's 20 mpg number. Retaining the Porsche driving dynamics will be the harder part of the equation.