Here are pictures of the Cayenne hybrid system:
UPDATE:
Chris Wall, manager of automotive and product information at Porsche, tells us the Panamera hybrid will share the parallel gas-electric drivetrain planned for the Cayenne and Porsche is committed to incorporating the technology into its lineup.
"It's definitely part of our overall plan," he says.
More info and diagrams of the Panamera and Cayenne hybrid systems after the jump.
Porsche and Volkswagen worked together to develop the parallel hybrid system, which VW reportedly is planning to offer in the Touareg as soon as next year. Wall said it will provide 30 percent better fuel economy than the gas-only versions of the Cayenne and Panamera.
"We've reached that goal," he says of the fuel efficiency improvements. Porsche's engineers found that the hybrid system also brought gains in acceleration and torque, but Wall could not provide specifics. The system uses nickel metal hydride batteries; Porsche is investigating other options, Wall says, "but the technology just isn't there yet."
Wall says the Panamera and Cayenne hybrids will feature 3.6 liter V-6 engines producing 290 horsepower and a 38 kilowatt electric motor (not the 34 kilowatts we reported earlier). The engine, electric motor and transmission are controlled by what Porsche calls Hybrid Manager, a system that monitors 20,000 data parameters for optimal power and efficiency.
To further improve fuel economy, the Cayenne hybrid uses electrical power steering, air conditioning and brake vacuum pumps instead of engine-driven components and the six-speed automatic transmission features an electric oil pump. Porsche expects the Cayenne hybrid to deliver 24 mpg and hopes to improve that to 26 mpg.
Wall says Porsche "definitely" plans to produce the Cayenne hybrid by 2010. There's no word on when the Panamera hybrid might appear, and Porsche's been tight-lipped about the Panamera in general since announcing it more than two years ago - so much so that the sketch we've included is the only official rendering of the car Porsche has released.
Porsche is serious about hybrids, Wall says, telling us, "It's a technology that can go hand in hand with Porsche performance. You can have, with this parallel system, savings in city and highway fuel consumption and increases in performance."
So does that mean we'll see hybrid versions of the Boxster, Cayman and 911?
"It's possible, yes," Wall says. "I don't think the technology is there right now, but in the future... Our engineers are always looking to see what technology is available, and in a lot of cases, what technology they can create."
Porsche provided this diagram of the Panamera Hybrid system: