Land Rover's 100g/km hybrid

Land Rover is engineering a Range Rover Sport hybrid that it claims will emit just 100g/km of CO2 and could offer an electric-only range of as much as 20 miles.

The vehicle will be driveable next year when a small fleet of up to five prototypes start shakedown tests ahead of a 2012 sales launch.

If it can be achieved, the low CO2 figure will be a significant breakthrough for the luxury brand, and it will move the Range Rover Sport’s carbon emissions onto an equal footing with those of smaller, lighter vehicles like the Citroën C1 and Ford Focus Econetic.

It would also considerably undercut the market’s sole hybrid SUV, the Lexus RX450h, which emits 148g/km of CO2.

The Range Rover will use the new 3.0-litre V6 diesel motor and feature a parallel arrangement for the 25kW electric motor, which will allow it to run as an all-electric vehicle, just like a Toyota Prius.

Land Rover isn’t divulging how it will achieve the 20-mile electric-only range, but the car is understood to operate as a plug-in and surplus electrical energy will be stored in a conventional battery pack.

It is also clear that this first-generation Land Rover hybrid will feature conventional storage of the electrical charge rather than the ultra-capacitors that the firm has been testing.

Ultra-capacitors deliver high voltages but low currents. The technology is said to be particularly suitable for Land Rover because the short, sharp energy boost that capacitors can deliver is well suited to off-road driving.

The advanced ERAD electric rear axle design that was demonstrated last year in the Freelander looks to have been ditched in favour of a more conventional hybrid set-up.

Julian Rendell

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