Porsche first displayed a prototype Cayenne Hybrid S back in November 2007 at the Los Angeles Auto Show, but after more than two years, the “green” SUV has yet to hit dealerships. Now Porsche says that the Cayenne Hybrid S is still about a year away from production.

A Porsche board member has gone on record saying that the hybrid Cayenne will be on sale by the second half of 2010. That coincides with the launch of the redesigned 2011 Cayenne, which is destined to become a crossover, rather than an offroader. The Cayenne Hybrid S will apparently retail at prices starting from an astronomical $124,500 in Europe.

Porsche says the Cayenne Hybrid S will offer V8 power with four-cylinder efficiency. The Cayenne Hybrid S will use an Audi-sourced 33 hp 3.0L V6 with 324 lb-ft of torque, and an electric motor will add another 52 hp and 221 lb-ft. That is enough to get the Cayenne Hybrid S to do the 0-60 run in 6.8 seconds.

The Cayenne Hybrid S will have 20 percent less CO2 emissions than its gasoline counterpart — good enough to qualify it for ULEV II status. Porsche hasn’t released official fuel economy figures for the Cayenne Hybrid S yet, but early reports suggest the SUV could hit 32 mpg on the highway, about 10 mpg better than the base V6-powered Cayenne.

Porsche also revealed the Cayenne Hybrid S will be capable of traveling up to a pathetic 1.2 miles on pure electric power, with the gas engine kicking in within 380 ms when needed. Additionally, the Cayenne Hybrid S will be able to maintain electric power alone all the way up to 86 mph.