Hydraulic engine innovation waves goodbye to high fuel consumption

A small Scottish firm has developed technology based on systems more commonly found in an offshore wave energy farm that promises to halve the fuel consumption of a conventional car.

Artemis Intelligent Power announced this week that it has successfully retrofitted a BMW 5-series saloon with its Digital Displacement technology, reducing its emissions by over 30 per cent in combined road and city driving.

"The system will be much less expensive than electric hybrids and will help to make hybrid vehicles an economic, rather than a lifestyle, choice," Win Rampen, director of Artemis, told BBC News.

The system, known as Digital Displacement, uses a hydraulic drive to convert energy that is usually wasted during breaking into fluid waves.

These slow and irregular waves are converted into a steady supply of power for electrical generators, using a technology pioneered in wave energy farms.

The car then runs on a mixture of stored energy and petrol, with a computer automatically adjusting the blend to the most efficient combination at any one time.

More traditional hybrid-electric cars work in a similar way, harnessing wasted braking power to charge an electric battery. But Artemis argues that its approach will prove more efficient as it is significantly lighter than the batteries found in conventional hybrids.

Artemis was set up in 1994 by Edinburgh University researchers. The BMW project is part-funded by the Department for Transport and the Energy Saving Trust.

The company already has licensing contracts with vehicle manufacturers Bosch Rexroth and Sauer-Danfoss APS, and hopes the technology will be installed in some agricultural vehicles and HGVs within three years.

Bosch Rexroth plans to use the company's technology in on-highway vehicles, while Sauer-Danfoss has said it will use the hydraulic systems in its con struction, agricultural and handling machinery.