Over the past few years, it's become clear that the German prestige makers are determined to offer plug-in electric vehicles across their various ranges.
Some makers are more aggressive (BMW), some less so (Mercedes-Benz)--but by the end of next year, there will be a dozen or more vehicles with plugs from the combined forces of Audi, BMW, Mercedes-Benz, Porsche, and Volkswagen.
The latest to be officially announced is the 2015 Porsche Cayenne S E-Hybrid, which adds a plug-in hybrid powertrain to the sports car maker's large, fast, and very profitable sport-utility vehicle.
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The Cayenne, now in its second generation, has been offered both with hybrid and diesel powertrains, though neither has sold in particularly high numbers in the U.S. market.
2014 Porsche Panamera S E-Hybrid
The plug-in hybrid system used in Porsche's SUV for 2015 is identical to that already on sale in the 2014 Porsche Panamera S E-Hybrid.
It comprises a supercharged 3.0-liter V-6 with a 70-kilowatt (95-horsepower) electric motor sandwiched between the engine and an eight-speed automatic transmission.
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The company's engineers say the conventional automatic works more smoothly with the E-Hybrid's electric motor than the dual-clutch transmission used in gasoline models would.
A 9.4-kilowatt-hour lithium-ion battery pack powers the electric motor; it replaces the 1.7-kWh nickel-metal-hydride pack used in the Cayenne S Hybrid. Total output is above 400 hp.
2015 Porsche Cayenne S E Hybrid
The plug-in hybrid version of the Porsche Panamera luxury sedan has actually replaced the previous Panamera S Hybrid version, though it's not clear whether the same will apply to the Cayenne SUV model range as well.
The plug-in hybrid Panamera is selling in slightly higher numbers than its plain hybrid predecessor.
That's likely due to incentives that include carpool-lane access and a purchase rebate in California, a Federal income-tax credit, and various other state and local programs to encourage sales of plug-in electric vehicles.
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Oh, and that third plug-in vehicle from Porsche?
That would be the limited-edition Porsche 918 Spyder, the very high-performance plug-in hybrid supercar--at price approaching one million dollars.
The plug-in hybrid Cayenne, on the other hand, will likely come in somewhere between $75,000 and $100,000.