Riversimple Hydrogen car to begin Leicester trials

11 June 2010 | By Stephen Harris

The city council and car manufacturer Riversimple have agreed to lease 30 of the cars to motorists under a 12-month pilot scheme also involving Leicester and De Montfort universities.

Leicester was chosen because its manageable size meant it would only need one hydrogen fuel pump. If successful, the pilot could lead to the city becoming the location for a Riversimple factory producing 5,000 cars a year.

The firm is expected to announce a second agreement with another city soon.

‘The age of fossil-fuelled cars may not be over yet but it is surely dying,’ said Riversimple founder Hugo Spowers at the car’s launch in Leicester yesterday. ’Contrary to what we usually hear, sustainable, near pollution-free transport is possible, here and now, using existing technology.’

Riversimple spokesperson Charlie Burgess told The Engineer the leasing model would help further reduce the cars’ environmental impact.

‘The whole model of how car sales run is completely unsustainable,” he said. ’Rather than buying new a car and then selling it and buying another one three years later, this will keep the original cars on the road for as long as possible.’

With costs estimated at around £200 a month plus fuel and with no initial outlay, the leasing system could also make driving cheaper.

The 350kg car is powered by a 6kW fuel cell and has a 240 mile range, a top speed of 50mph and energy efficiency equivalent to 300mpg of petrol.

The high level of efficiency is provided by the car’s separate systems for accelerating and cruising, and its lightweight design.

Most cars only accelerate for around five per cent of the time they are on the roads but use about five times the amount of power as when they are cruising, so the Riversimple car decouples energy production for the two processes.

Ultracapacitors capture waste energy from the brakes and reuse it for accelerating, meaning the fuel cell only needs to provide the smaller amount of power for cruising.

The smaller fuel cell and the removal of a gearbox and driveshafts reduce the weight of internal components. Under a principle known as mass decompounding, this means the car can also have a lighter chassis to support the engine and therefore needs even less power.

A lighter car also makes power-assisted brakes and steering unnecessary and so more mass decompounding and efficiency improvements can take place.

This effect is further magnified in the Riversimple car by the use of lighter, composite materials for the chassis.

Click here for a more in depth look at the concept from The Engineer.