By Bill Moore
I could have sworn the Imperia GP was a real car. The high-resolution images on the company web site are so realistic that they've fooled others besides me.
"Maybe they are too realistic," admits Yves Toussant, a founding member of Green Propulsion , a Liege, Belgium-based automotive testing and prototyping firm that has resurrected the long-dormant Imperia brand. With plenty of real hardware experience, Green Propulsion (GP) opted to first explore the potential market for a plug-in hybrid two-seat sports car by having it designed on a computer and then rendered into the life-like reality you see above.
The response has been promising enough that GP has begun work on their "mule", the rolling platform on which they will test their propulsion system that also includes the first use of a new V-4 internal combustion engine now in development by Weber in Germany.
As you can imagine, the story of how GP came to resurrect the Imperia brand name is a fascinating one that began some four years ago and includes, along the way, a student design contest that produced the stunningly classic styling of the concept car illustrations on the web site.
A century ago, according to Toussant, there were some 100 companies in the automotive business in Belgium alone. One of them was Imperia, which began manufacturing cars in 1904. The company reached its heyday in the 20s and 30s after a string of racing successes. Gradually, competition stalled all but two of the car companies in Belgium, finally taking down Imperia in 1958. Once considered the Belgium sports car equivalent of Rolls Royce, it was relatively simple for Green Propulsion to acquire the marque.
The Imperia project is an outgrowth of GP's research work on hybrid-electric drive systems that have spanned the range from karts to small urban buses. They developed a hybrid version of the Volkswagen Lupo and Renault Kangoo. In working for European carmakers, they came to realize that none of their clients were interested in developing a hybrid sports car, so they decided to create one themselves.
"In four years, we have developed the optimal drive for this application," Toussant explained.
There is some poetic justice in deciding to brand the project with the Imperia name. Back in its early 20th century heyday, Imperia cars were manufactured in the same building where the very first hybrid-electric cars where built more than a century ago by a Belgium company called Auto-Mixte. However, the original company never offered a hybrid version, Now, with the help of 21st century technology, its reincarnation hopes to correct that short-coming.
In deciding to resurrect the Imperia marque, Toussant and his colleagues wanted their design to reflect some of the styling cues of the original vehicles, much along the lines of what Volkswagen did when they revived and updated the original "Bug" in the New Beetle. BMW did the same with the very popular Mini Cooper, as did Fiat with its 500. Acquiring the actual brand name was simply a matter of registering it, since by 2004, no one owned it any longer.
Around the same time, GP issued a competition call among design students to come up with a design for the new car. Denis Stevens was the winner of that competition, not only creating the neo-retro look the company was looking for, but doing it with such realism as to virtually bring the car to life, setting it on a beach, in the middle of a town square and racing down a road in Belgium. Collaborating with GP's engineers, Stevens continues to refine the vehicle with safety and production goals in mind.
The choice of hiring Stevens and moving forward in a "virtual" development environment has been driven largely by economics. The Imperia program is being solely funded by GP. Toussant explained that they needed to create a balance between finding a good design and keeping the project within budget. That meant hiring a "professional" automotive designer was out of the question. In Stevens, they came upon a bright, rising talent at a price they could afford.
As you'll discover when you listen to the MP3 interview -- using either of the two players above -- that for better than half of the interview, I continued to labor under the erroneous assumption that the car actually existed, asking questions like, What might I expect to experience when driving the car? Of course, the real answer would be "nothing" since there is, at the moment no car to drive. But Toussant has a good idea of how he believes his drive system and target vehicle will perform.
Since keeping the weight of the car down is crucial to its handling and performance, GP is aiming for a curb weight of just 850 kg (1,873 lbs ). GP estimates CO2 emissions at 120 g/km in hybrid mode and 80 g/km in electric-only mode (taking power plant emissions into consideration), which is achieved by simply putting the car in neutral. The car will have a manual transmission with an automatic clutch.
According to Toussant, GPs design has a very high ratio of electric-drive to gasoline engine hybridization in a parallel arrangement. The newly developed Weber V-4 gasoline engine will sit under the hood of the car and drive the 5-speed manual transmission, Behind this is the electric motor (see illustration below) through which the drive-line passes. The car is rear wheel-drive. The lithium polymer battery pack is mounted behind the passenger seats.
The reason for selecting the V-4 is to allow for smaller engine displacement (1.6-2.0 liter) and packaging, while offering a much smoother, less vibration-prone engine with a great acoustical exhaust signature. Toussant expects the first production versions of the engine in early 2009, with prototypes for testing in his vehicle before that.
The tubular steel frame chassis weighs just 90 kg (198 lbs) so GP doesn't see the need for using either aluminum or carbon fiber. The body panels are fabricated out of polyester resins.
The car's weight is also kept low by minimizing the number of accessories in the car.
"It is quite basic," Toussant said.
If buyers want to customize the car with added features, GP has arranged with a local luxury car customizer to handle special orders.
GP chose its unique parallel hybrid-drive set up in order to improve its overall efficiency, noting that placing the motor behind the transmission instead of between the engine and transmission is a more efficient approach to maximizing the performance of the car. The V-4 is rated at 130kW and the electric induction motor is rated at 100 kW, giving the car a combined rating of 230 kW or the equivalent of 308 hp. The lithium polymer battery pack is 266 volts with a capacity of 31 amp hours of energy, enough to propel the car 60 km (37 mi.) in electric-only mode. Toussant told me the energy density of the li-polymer cells are 130 Wh/kg -- nearly 7x better than lead acid -- while the power density is more than 1,500 W/kg. The 3kW charger is built into vehicle and capable of recharging it at 220v at 16 amps to 85% of capacity in 3 hours and 100% in 4 hours.
From a vehicle dynamics perspective, the Imperia's drive system is nearly ideal with the weight fairly evenly distributed front and back, which is ideal for a performance roadster.
From Virtual to Real
It took me some 27 minutes to finally grasp that what we'd been talking about all this time was "theory." It was while discussing GP's plans for manufacturing the car in Liege that it suddenly dawned on me that what I'd assumed were at least four different prototypes, based on the different body colors in the images, were only computer simulations -- dang this software is getting good!
Toussant explained that after posting the images on the web site last month, it only took a week to get sufficient feedback and expressions of interest in ordering a vehicle to decide that they should move ahead with development. At the moment the company is working on solidifying those expressions of interest and deciding how many vehicles to manufacture. He estimates that they could produce in the Liege facility between 25 and 100 cars a year. The €85,000 (US$130,00 ) price tag is based on selling 50 cars a year.
As the company works out the details of starting production, it also is focusing on its drive system mule, which is built on the chassis of "very old" 1970 Ford Escort NK1. It is equipped with a hybrid system very close to what will be integrated into the Imperia; calibration testing and data collection should begin in the next few weeks.
Now that I understood what manner of "beast" I was dealing with, I asked Toussant about issues like European homologation, international sales and battery management. But to hear his answers, you'll want to listen to the interview using either of the two MP3 players above or by downloading the file to your computer hard drive for transfer to your favorite MP3 player.
For me the larger lesson from "Resurrecting Imperia" is the seismic shift it potentially represents in automotive marketing and manufacturing, where customer interest and even pre-sales can be generated online through really good design and convincing computer graphics at also just happen to include all the required engineering CAD-CAM data just underneath that glossy, life-like paint scheme. I could envision a time in the not too distant future where hundreds or even thousands of "virtual car companies" like Imperia may someday spring up and working in conjunction with established chassis and drive-system manufacturers, will be able to "virtually" manufacture custom-designed vehicles that are not only energy efficient, but just plan "cool."
Maybe what "Imperia" truly represents is the end of the cookie-cutter car and the beginning of creative, fun and environmentally-responsible motoring choices.