Porsche has put an end to rumours of hybrid aspirations by confirming not one, but two hybrid models. The 911 is sacred ground, and will be left alone for the time being, but the first Porsche to get a hybrid propulsion system will be the Cayenne SUV.
The second hybrid vehicle from Porsche will be the 2009 Panamera, which will also be the German sports car company's first 4-door grand tourer. This also adds fuel to the claims that the new Panamera will be powered by engines lifted from the Cayenne models, namely V8 power.
The new Porsche Cayenne Hybrid returns average fuel consumption figures of 9.8 liters/100 kilometers (24mpg). This is a good figure for a luxury SUV. Porsche believes that it can better this figure saying "...future developments may allow Porsche engineers to push towards an average fuel consumption figure of 8.9 liters/kilometer (26mpg)".
Aiming to lower the fuel consumption of its SUV, Porsche is currently testing a Cayenne hybrid prototype and is talking about reducing fuel consumption by 25%. Porsche hopes to have hybrid technology available in two models by the end of the decade, by essentially adding a "hybrid module" (clutch and electric motor) to the standard petrol engines.
This hybrid module is positioned between the combustion engine and the transmission rather than having the hybrid drivetrain branching output along various lines and in various directions via a planetary gearset. The reasoning behind this decision is two-fold. Firstly, it fits easily into the Cayenne's underpinnings. Secondly, "it will provide improved acceleration and engine flexibility" says Porsche.
The three major elements of the new Porsche hybrid system - the combustion engine, the electric motor, the battery – are controlled by what Porsche is calling "the heart of the Cayenne Hybrid", the Hybrid Manager. According to the German company, it oversees some 20,000 data parameters and claims it to be "one of the most powerful technologies found in any hybrid vehicle".
The battery type for the current test mules are nickel-metal hydride, which are not as powerful as lithium-ion batteries used by some car makers. The battery can be recharged via energy regeneration from the brakes.
Porsche also plans on combining some of the cars systems to further reduce fuel consumption. As such, the Cayenne Hybrid's power steering and vacuum pump for the brakes, as well as the air conditioning, all operated on electric power to reduce strain on the engine. Furthermore, the the oil pump for the Cayenne's automatic transmission has also been modified to run from electricity. Electro-hydraulic steering is also planned.
Unlike another luxury hybrid SUV, the Lexus RX400h which cannot go off-road, Porsche says the Cayenne will retain its rugged go anywhere character, and can still ford rivers and creeks.
Porsche Cayenne Hybrid
Porsche admits that it's hybrid performance in
the city is not yet on par with similar systems used
by Toyota, but says that highway driving is frugal
