Porsche Debuts Concept 918 Spyder Plug-in Hybrid Concept at Geneva
03 March 2010
| Phantom diagram of the 918 Spyder with plug-in hybrid technology. Click to enlarge. |
In addition to introducing the flywheel KERS equipped 911 GT3 R hybrid for production-based GT racing (earlier post) and the Cayenne S Hybrid (earlier post) at the Geneva Motor Show, Porsche unveiled the plug-in hybrid Porsche 918 Spyder concept car.
The mid-engined two-seater is powered by a high-speed V8 developing more than 500 bhp (373 kW) and running at maximum speed engine of 9,200 rpm as well as electric motors on the front and rear axle with overall mechanical output of 218 bhp (160 kW). Porsche says that concept combines the performance of a super-sports car with the CO2 emissions of a small compact, with fuel consumption of 3.0 L/100 kilometers (78.4 mpg US) and 70 grams CO2 per kilometer in its most economical operating mode.
| Michael Macht, the President and Chief Executive Officer of Dr. Ing. h.c. F. Porsche AG and Walter Röhrl presenting the Porsche 918 Spyder concept car before the opening of the Geneva show. Click to enlarge. |
Acceleration from 0 to 10 km/h takes less than 3.2 seconds, and the 918 concept has a top speed of 320 km/h (198 mph), and a lap time on the Nordschleife of Nürburgring in less than 7:30 minutes—faster than the Porsche Carrera GT.
The V8 combustion engine is a further development of the 3.4-liter power unit already featured in the RS Spyder racing car. Power is transmitted to the wheels by a seven-speed Porsche-Doppelkupplungsgetriebe also feeding the power of the electric drive system to the rear axle. The front-wheel electric drive powers the wheels through a firm transmission ratio. A grid-chargeable liquid-cooled lithium-ion battery pack is positioned behind the passenger cell.
A button on the steering wheel allows the driver to choose among four different running modes:
The E-Drive mode is for running the car under electric power alone, with a range of up to 25 km (16 miles).
In the Hybrid mode the 918 Spyder uses both the electric motors and the combustion engine as a function of driving conditions and requirements, offering a range from particularly fuel-efficient all the way to extra powerful.
The Sport Hybrid mode uses both drive systems, but with the focus on performance. Most of the drive power goes to the rear wheels, with Torque Vectoring serving to additionally improve the car’s driving dynamics.
In the Race Hybrid mode the drive systems are focused on pure performance with the highest standard of driving dynamics on the track, running at the limit to their power and dynamic output. With the battery sufficiently charged, a push-to-pass button feeds in additional electrical power (E-Boost), for example when overtaking or for even better performance.
The modular structure with its monocoque bodyshell made of carbon-fibre-reinforced plastic (CFP) and the appropriate use of magnesium and aluminium reduces weight to less than 1,490 kg (3,285 lbs).
It is difficult to believe that such a powerful car is using less fuel than a Prius. However, it may be true as this car has 1) about same weight as the Prius, 2) probably has a lower drag coefficient, 3) has better regenerative ability with its 160kW electric motors versus the Prius’s 60kW, 4) has better ability to operate the combustion engine only at peak performance because the electric power is higher and 5) because it uses a lithium battery that probably is 95% cycle efficient versus probably only 85% cycle efficiency for the Prius’s NiMH battery.
If Porsche’s mpg rating is true it is a really spectacular case of how efficient hybrid technology could be without sacrificing the fun factor of driving.
Posted by: Account Deleted | 03 March 2010 at 03:16 AM
Yes, and since "The E-Drive mode is for running the car under electric power alone, with a range of up to 25 km (16 miles)." it all depends on how/when you measure MPG.
Posted by: ToppaTom | 03 March 2010 at 05:13 AM
It is more like mpgge...miles per gasoline gallon equivalent. It takes energy to produce the electricity. Measure the electricity put into the car when plugged in, calculate how many BTUs it took to create that electricity and see how many miles you get on it.
If it takes the same BTUs that are in a gallon of gasoline to generate the 10 kWh that goes into the car and I can go 40 miles on that, then I get 40 mpgge. It makes no sense to do phony accounting and claim the PHEV gets more than 100 mpg when that is misleading.
Posted by: SJC | 03 March 2010 at 06:14 AM
They got the specs, but if your afraid to ask the price..
Posted by: kelly | 03 March 2010 at 07:21 AM
Ok I will admit that when I first saw this car two days ago, on a autoblog, I drooled. So sue me, I like Porsches.
Posted by: ai_vin | 03 March 2010 at 10:32 AM
To further understand how they get so good mileage figures, you have to remember that these figures are obtained by a test on a predefined cycle. This cycle was defined in the 60s (even if they say New European Driving Cycle, the New only refers to the fact that before 1990, they started measurements at 40s instead of 0s now) and it doesn't have any steep accelerations. With a Porsche, you tend to put your foot down a little more so you get much higher consumption figures in real life.
Just for the anecdote, on the American cycles (defined in 1969 for the FTP and at the beginning of the 70s for the HWFET), steep accelerations were erased because the roll benches couldn't handle these kind of accelerations.
web.mit.edu/sloan-auto-lab/.../files/IreneBerry_Thesis_February2010.pdf
Posted by: Simodul | 04 March 2010 at 04:41 AM
My only question is why they didn't have the balls to incorporate supercaps (or a supercap/battery hybrid energy storage system) in the car? The Supra HV-R demonstrated the benefits and surely, on such a car costs aren't much of an issue to prevent it from happening?
Posted by: dieqast | 10 March 2010 at 04:14 PM