As the Tesla Model S was approaching its release date last year, chief designer Franz von Holzhausen answered a series of questions posed by participants in an online forum focusing on the capabilities of the company’s latest offering in the electric vehicle marketplace:

How would you describe your philosophy and approach when you first designed the Model S?

How do you translate inspiration into a real product?

A vehicle’s design is a living sculpture, a fluid object. We spend hours defining and redefining the surfaces, tension, line, and weight balance using a clay sculpture. Just like that endurance athlete honing her body day in and day out, we continuously sculpted the shape for better performance.

Our goal is to modernize the design of the classic sedan silhouette and make it unique to Tesla. To do this, we streamlined the greenhouse (the area enclosed by windows) and stretched it to feel lower and leaner than usual. We wanted it to express speed and motion, even when at rest. I think we’ve accomplished that goal.

What are some of the changes that were made to the prototype?

Most traditional automotive prototypes look very little like the cars that make it on the road. In previous jobs at other car companies, I’d hand off a design to production and my input ended. Not so at Tesla.

Tesla’s design team created the design prototype with fundamental understanding of the realities of production. We forged a tight relationship with the vehicle and powertrain engineering teams to maintain tight communication throughout Model S development. For example, if you look at the Model S Alpha from the side, and compare that to the design prototype, the centerline (the curve from the hood to the rear of the car) has not changed. From the outset, we designed the exterior to contain the right interior volume. Every millimeter of the car has been considered by the design and engineering teams. This close teamwork is unique to Tesla.

What were the biggest challenges in designing the Model S?

The freedom of having a blank slate was also my biggest challenge. In addition to defining Model S, Tesla’s brand is still evolving. We’re just starting to create the design language that defines “Tesla” as a brand of vehicles. It’s incredibly exciting.

If you had to pick one aspect of the vehicle that is truly a step forward for the automotive industry, what would it be?

The architecture. Model S is a revolutionary vehicle: not only due to its electric propulsion, but also in that its engineering and design go hand-in-hand. We have designed Model S from the ground up as an EV. The unique powertrain integration allows for an unprecedented package that is both rigid and incredibly safe. We set out to redefine the electric car, but with room for seven passengers and more functional storage space than any sedan on the market, Model S will set a new bar for the premium sedan as well.

Are you keeping the awesome door handles?

Yes! Door handles will be flush to the body of the car on every Model S. The handles are people’s first point of contact with the car. They should feel solid and inspire confidence, but they should also lend to the aerodynamics of the vehicle. That’s why I wanted the handles to be more of an accent, appearing when needed. As planned, they will only present themselves when passengers approach the car. Making the handles flush to the body improves airflow down the body’s sides, reducing the drag coefficient and extending range.

The prototype’s fenders wrap closely around the wheels. Is this the same on the final production version?

Yes. We paid close attention to balance and stance as we developed Model S. We put quite a bit of effort into the interaction of the wheel and the body. We focused on creating the impression that the wheels are supporting the body, flush and tight to the openings with minimal gaps. It was really important to me that the car didn’t feel over-bodied to the wheels or overweight.

The Roadster uses carbon fiber composites for aesthetic accents and the body panels. What about the future Tesla cars?

For limited or low-volume production cars like the Roadster, carbon fiber is a great material to reduce weight. It’s not a solution for higher volume production due to cost and manufacturing time. For Model S, we are using aluminum for the body panels and chassis. Aluminum is as strong as steel but lighter in weight, and has similar manufacturing capabilities. Lighter weight translates directly to efficiency.

The prototype cars had fantastic-looking light-pipe rear running lights; does the final design retain distinctive rear lighting effects?

Absolutely. The lighting on the Model S helps produce a distinctive look for Tesla. The “wow” factor should be just as powerful looking head-on in the bright sunlight as it is at night in a rear-view mirror.

Where is the charge port located?

The charge port is located toward the rear of the car, on the driver’s side. The majority of charging happens at home so this is the most functional location. Similar to the door handles, the charge port door hides when not in use. It was important to me to make charging a unique experience. The charge port looks nothing like a traditional fuel door.

For more information, visit www.teslamotors.com.

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