Porsche has announced that its 918 hybrid 760 bhp hypercar has started testing on the road prior to its launch in 2013

The new Porsche is not simply another supercar in the mould of the Porsche Carrera GT or even the Bugatti Veyron. The Porsche 918 is an attempt to combine all the traditional elements of a supercar with the fuel consumption of the most economical supermini – at least on the official tests.

The drivetrain consists of a 560 bhp 4.6 litre V8 petrol engine plus two electric motors - one on the front axle and one in the drive line, acting on the rear wheels – which add another 200 bhp. Porsche says, "What we are doing with the 918 Spyder is redefining driving fun, efficiency and performance."

Thanks to the plug-in hybrid system, the 918 can be charged off the mains and will run for up to 15 miles on battery power alone. That will enable it to achieve amazing fuel economy figures in the EU tests: expect an official fuel consumption of up to 90 mpg. In actual use, owners are more likely to see half of that – or a lot less on a long high speed run. Still 918 owners are not likely to be complaining about refuelling costs.

The combination of huge bhp plus the instant torque (pulling power) of an electric motor could make the 918 the most exciting supercar yet (stand by for 100 road test headlines using the word "electrifying"). With electric motors front and back, Porsche can also set up the handling characteristics to be almost anything it wants – it could behave as if was front-engined, mid-engined or rear-engined depending on how the power is distributed.