Having launched its first production hybrid vehicle, the Cayenne S petrol-electric offering, Porsche seems intent on pushing for alternative powered automobiles throughout its range.
Sharing Porsche’s 2010 Geneva Motor Show stage alongside the aforementioned Cayenne, as well as the 911 GT3 R hybrid, was the 918 Spyder concept. The mid-engined two-seater offers a claimed fuel consumption of 94 mpg and adopts a plug-in approach to hybridization, which complements the full hybrid Cayenne, and flywheel-equipped racing 911 GT3.
The 918’s 3.4-L V8 engine puts out more than 500 bhp (373 kW) and has been developed from the unit found in the RS Spyder racing car. Mounted just in front of the rear axle, allowing the optimum performance for race and road, the eight-cylinder powerplant is supplemented by two electric motors—one mounted on the front axle and one on the rear. Combined, these two power sources supply 160 kW.
Porsche engineers have given drivers of the 918 a choice of four modes of operation, selected via a steering-wheel mounted button.
In E-Drive mode, the car can cover up to 16 mi (26 km) on electric power alone. Providing the power is a fluid-cooled lithium-ion battery pack that is behind the passenger cell. In Hybrid mode, the car makes use of both electric motors as well as the power from the V8, giving the choice of maximizing vehicle range or enjoying the performance potential of the car. Sport Hybrid mode takes the driving dynamics one stage further through torque vectoring, while the majority of the power is channeled through the rear axle. Finally, in Race Hybrid mode, there is an option of additional electrical power available (Porsche is calling it the E-Boost), used for overtaking and further improved performance.
The body structure of the 918 has been designed with race potential in mind with a carbon-fiber-reinforced plastic (CFRP) monocoque sitting on a chassis making good use of aluminum and magnesium to help the car weigh in at 1490 kg (3285 lb).
A further function, more likely to make production than the car itself, according to Porsche, is Range Manager, which uses the navigation system’s map to indicate how much of the journey is possible in the car’s range. The system will also indicate whether a destination can be reached on electric power alone, and it alerts drivers to improvements in range through using the full potential of the hybrid powertrain.
While it is designed with hybrid power as a central theme, there is no doubting the performance potential of the vehicle. Porsche claims that the car can lap the Nürburgring’s Nordschleife in under 7.5 min, which is faster than the Porsche Carerra GT. The Spyder can also reach 100 km/h (62 mph) from a standstill in 3.2 s and go on to a top speed of 198 mph (319 km/h). On the other end of the scale, however, the company says emissions levels as low as 70 g/km CO2 can be achieved.