An in-house engineering team and two major component suppliers have together developed Land Rover's new fuel-saving stop-start technology which will be available on manual diesel Freelander models from next May.

A Land Rover spokesman said the control system was developed by the automaker's engineering centre at Gaydon, Warwickshire, while Bosch provided the engine management and Denso contributed an uprated starter motor.

The system will be available on all manual versions of the 2.2 litre diesel TD4 model which accounts for about half of all Freelander sales here in the UK.

It's the first result of the Tata Group-owned automaker's GBP800m investment over five years in new environmental technology.

"We will reduce CO2 output of our vehicles without comprising our values," said Murray Dietsch, director of Land Rover programmes. "We still have to have the best vehicles for the toughest conditions."

He described stop-start as the first step on Land Rover's green technology road map which will eventually lead to a diesel hybrid 'Landie' capable of 60mpg and with emissions below 120g/km.

"Downsizing is an important part of our future; we will have more compact, lighter vehicles with greater aerodynamic efficiency, low rolling resistance tyres and electric power steering among a long list of measures," said Dietsch.

Stop-start on its own reduces CO2 emissions by 8%, taking the Freelander from 194g/km to 179g/km and reducing the owner's annual road tax (and tax on company cars) here in the UK.

Phil Wiffin, manager of stop-start systems at Land Rover, said that, on a typical 40-minute journey in London, a vehicle's engine is only needed for about 19 minutes.

"We're saying this is the world's first intelligent stop-start SUV. Fuel consumption in these conditions is improved by 12% which is a saving of GBP13 (about US$20) on a tank of diesel at today's prices on a typical London test route."

At the moment stop-start is only available with manual gearboxes but it will also be adapted for use with automatic transmissions and rolled out in other Land Rovers from around early 2011.

Features includes sensors which will automatically restart the engine if the cabin starts to get too cold or too hot so that the air conditioning operates; this also works if the windows start to mist up. The engine also restarts automatically if the Freelander starts to roll more than six feet (two metres).

There will be no price increase for stop-start-equpped Freelander models which will be badged 'TD4-e'.

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