Wrapping up our series of articles generated from a roundtable discussion with Porsche chief Matthias Mueller, management board member for sales and marketing Bernhard Maier, and Porsche Cars North America chief Detlev von Platen at the Geneva Motor Show, we take a look at the near future of Porsche's vehicle lineup.

Fuel efficiency is a major theme, as it is with the industry as a whole, but the constant undercurrent of any discussion with these heads of Porsche's empire is performance. Whatever they build, for whatever reasons, it must be a sports car--or at least must feel like one. With the Cayenne and Panamera, Porsche has proved it can do something besides the classic sports car format while maintaining performance. Soon, we'll see how well they do plug-in hybrids, among other things.

First up, the Macan

The Macan compact crossover will be an obvious target for improving fleet fuel economy averages. A "four-cylinder makes sense" for the Macan, says Bernhard Maier, though it won't be a boxer-style engine, as it wouldn't fit the platform.

It will also be targeted at a new sort of buyer for Porsche: more urban, younger, and likely more concerned with fuel economy and price. As the fastest growing segment in the industry as a whole, Porsche wants a piece of the B-segment SUV pie.

Porsche CEO Mueller says a "cautious estimate" of Macan volume at the outset is 50,000-55,000 units per year. Some of that volume will likely come from the entry-level end of Cayenne sales, says Mueller--about 10 percent. The rest, however, will be buyers new to the brand.

2011 Porsche Cayenne Hybrid

2011 Porsche Cayenne Hybrid

Next, the Cayenne and Panamera

It's no secret Porsche's fellow VW Group brands Bentley and Lamborghini have their radars locked on their own SUVs, and Lamborghini may also have a sedan based on the Estoque concept waiting in the wings. Where does that leave Porsche?

Just where it is, says Mueller. Even though Lamborghini and Bentley are entering a similar segment, there's "no real overlap" between them due to differences in price, size, and engines, he says.

That last part is elemental to the near future of both Cayenne and Panamera, as  Mueller is keen to build plug-in hybrid versions of both the Cayenne and Panamera "as soon as possible."

Another VW Group brand--Audi--has already confirmed its Q7 plug-in hybrid, and as the Q7 shares a platform with the Cayenne, that's likely to be the same technology that underlies the Porsche version--though with its own take on performance, range, and conventional engine. Audi's version isn't expected to arrive until 2014 or later, however, which probably puts Porsche on the same track.

Porsche Panamera Diesel

Porsche Panamera Diesel

What about diesel?

Mueller says "America must change its mind for Porsche to do so," when it comes to diesel engines. Detlev von Platen quickly interjects with, "things change very quickly in the U.S. and perception has already changed dramatically. Diesel makes a lot of sense for Cayenne," particularly in terms of torque and driving range.

There remains the hurdle of the perception gap: what Americans think of diesel and are willing to buy versus what Porsche thinks Americans think about diesel. BMW and Volkswagen have proved with their diesel sedans that America isn't completely opposed to the fuel, or blind to its potential benefits; the question is whether a diesel will be seen as fitting with Porsche's image in America. Oddly, Porsche has previously confirmed the diesel Cayenne for the U.S., but the tone of discussion at the roundtable in Geneva was rather less certain about diesel.

Diesel versions of the Cayenne and Panamera are already built and sold outside the U.S., so it would essentially be a matter of homologation for our market. With ratings like 36 mpg and 745 miles range while delivering 250 horsepower and 406 pound-feet of torque from a 3.0-liter V-6, as used in the Panamera diesel, it's not too hard to see that at least some of the American marketplace could find such a vehicle well within their idea of what it means to own a Porsche--and potentially bring new buyers to the brand.

For now, it's just a matter of time--waiting until the market is right. When may that be? Perhaps sooner than later, but we don't expect movement on diesel before 2014.

Porsche track design

Porsche track design

The Customer Experience

Also high on Porsche's list of focus items for the near term is an improvement in what it calls the "experience" of owning a Porsche.

To that end, the company is building tracks at its American headquarters in Atlanta and at an upcoming "Experience Center" in Los Angeles, where it will offer driving schools and other lifestyle and performance activities, helping to immerse owners in what it means to really drive a Porsche.

As von Platen put it, Porsche is "selling not only a car, but selling our experience." Expect this aspect of Porsche's activity to take on new and diverse directions as it works to build its brand--and as it seeks to maintain its image while branching out into the hybrid and diesel fields.

Porsche 918 Spyder Concept

Porsche 918 Spyder Concept

And a tiny teaser

Remember all of that talk about a super sports car nestled between the 911 and the 918 Spyder? Billed occasionally (by the media) as a Ferrari 458 fighter and rumored to be based on a Porsche-developed platform that will underpin the next Gallardo and R8, it's not entirely fictional.

At least, Porsche has engineers working on the car's exterior and interior designs, says Mueller.

What might such a tweener model look like, at least on paper? According to previous reports sourced to Mueller, it would likely be mid-engined, more fuel-efficient than current supercars, and also very high-performance. To do this, it would likely leverage aluminum and carbon fiber heavily in its core construction. A dual-clutch transmission and some sort of electric-assist drivetrain have also been rumored as part of the package.

Of course, as with all other Porsche projects, this may remain on the digital drawing board if the company can't find a way for it to work with the brand image and meet its necessary sales targets to produce profitability. "We are a small company, and can't do everything at the same time," said Mueller.