Rolls-Royce is working on a hybrid version of its upcoming luxury saloon, the Ghost.

The Rolls-Royce Ghost hybrid will share the BMW ActiveHybrid 7's green technology. The F01 7-series and the Ghost share the same standard rear-wheel drive platform, so the engineering on the Ghost hybrid has been fairly straightforward.

See the hi-res pics of the Rolls-Royce GhostFull details of the Rolls-Royce Ghost

The Ghost’s 6.2-litre V12 563bhp, 575lb ft petrol engine will be assisted by an electric motor in a mild hybrid application, with no electric only propulsion possible. An automatic start-stop system also comes into play to further reduce fuel consumption.

The car’s 20kW/155lb ft electric motor will be sandwiched into the car’s eight-speed ZF-engineered automatic transmission. Kinetic energy created during overrun and braking will be collected and stored in a 0.6kW/h lithium-ion battery pack mounted in the boot.

There will be no traditional alternator in the Ghost hybrid, with the engine being started via a 20kW electric motor, which should provide a smoother and quieter start-up.

Fuel consumption in the hybrid model should be around 15 per cent better than the standard model, while the extra torque and power provided by the additional battery should provide a subtle improvement to overall performance.

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