The deal to supply flywheel units looks like a very significant one for GKNs flywheel tech division - purchased from Williams earlier this year

The deal to supply flywheel units looks like a very significant one for GKN's flywheel tech division - purchased from Williams earlier this year

GKN plc and the Go-Ahead Group have agreed a deal to supply a flywheel-based system to London buses that it is claimed will improve fuel efficiency by around 20%.

The electric flywheel systems will be installed on 500 buses over the next two years.

The GKN system is based on Formula One race technology developed in the UK. It will help increase the efficiency of every bus to which it is fitted by using less fuel and therefore reducing carbon emissions. This same technology helped Audi's R18 e-tron win at Le Mans last month.

Go-Ahead has placed an order for GKN Hybrid Power to supply 500 of its Gyrodrive systems to the London buses transport operator. 

GKN Hybrid Power's Gyrodrive electric flywheel technology is a Kinetic Energy Recovery System (KERS). The Gyrodrive system uses a high speed flywheel made of carbon fibre to store the energy generated by a bus as it slows down to stop. It then uses the stored energy to power an electric motor which helps accelerate the bus back up to speed, generating fuel savings of more than 20% at a significantly lower cost than battery hybrid alternatives.

The agreement covers the supply of the complete Gyrodrive system, including the GKN Hybrid Power flywheel as well as GKN's EVO electric motor, a GKN designed and manufactured gearbox, and installation. The system is designed to last for the life of the bus eliminating the need for any battery changes.

Following successful trials on buses in London, Go-Ahead intends to utilise the technology in cities it serves across the UK, initially in London and Oxford.

Philip Swash, CEO GKN Land Systems, said: "This is an important milestone for GKN Hybrid Power. We've worked in close partnership with Go-Ahead throughout the development of this innovative technology and it's very exciting to move into the production phase.

"The fact that we are using the same groundbreaking technology that helped Audi win at Le Mans for the past three years to improve fuel efficiency in the public transport sector also shows what great innovation there is in the UK's engineering sector."

CEO of Go-Ahead, David Brown, added: "Our collaboration with GKN has been a most constructive one. We have a strong record in continually reducing our carbon emissions and flywheel technology will help us make buses an even more environmentally responsible choice and encourage more people to travel by public transport.

"The flywheel technology helps us to reduce our fuel consumption and C02 emissions so improving air quality for all those living, working and visiting the city."

GKN Hybrid Power is based in Oxfordshire, England, with final assembly taking place in a new facility at GKN's site in Telford, England. The Gyrodrive technology is being further developed for other mass transit markets including trams, construction and agricultural equipment.

Earlier this year GKN announced the acquisition of Williams Hybrid Power from Williams Grand Prix Engineering Limited to form GKN Hybrid Power, which is focused on delivering complete hybrid solutions across multiple vehicle, power and industrial markets.

GKN Hybrid Power's Gyrodrive electric flywheel technology is a Kinetic Energy Recovery System (KERS). When a vehicle brakes, it harvests the energy normally lost as heat. The flywheel stores the energy and returns it to the wheels on demand, boosting power, saving fuel and reducing emissions. When the driver brakes, a traction motor on one of the axles slows the vehicle, generating electricity at the same time. This electricity is used to charge the flywheel, spinning it at up to 36,000rpm. When the driver accelerates, the system works in reverse. The energy is drawn from the flywheel and converted back into electricity to power the traction motor. This reduces the work done by the internal combustion engine, improving fuel economy by up to 25%, depending on the application, it is claimed.

See also: UK: GKN acquires Williams Hybrid Power

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