Torotrak to showcase new hybrid bus technology

A UK-based company engineering firm Torotrak will showcase a new mechanical Kinetic Energy Recovery System (KERS) for buses at the upcoming CTI transmission symposium in Berlin.

The Flybrid mechanical KERS solution is claimed to be dramatically cheaper than a conventional battery hybrid system as used by other manufacturers. The company will set out the development and validation of its bus KERS, based on a Wrightbus StreetLite Midi bus which has been running in public service for nearly a year.

Torotrak’s Flybrid KERS uses a high speed flywheel to capture energy that would otherwise be lost as heat in the brakes when the bus is decelerating. This stored energy is then transferred mechanically back to the wheels and used to accelerate the vehicle, offering significant savings in fuel consumption, CO2 and other emissions.

The cost of the system is also predicted to be much lower than a battery electric hybrid, with Torotrak targeting operator payback times of less than five years.

The Flybrid bus technology won the SMMT Award for Automotive Innovation in 2014, being cited as a potential game-changer for the UK vehicle industry due to its affordability and low carbon credentials.

Tobias Knichel, Torotrak Business Development Director, said, “Our mechanical flywheel system is around a quarter of the cost of traditional battery hybrid technology and is ideally suited to the start-stop urban cycles experienced by public transport vehicles.

“Being a purely mechanical system, Flybrid KERS avoids the inevitable losses that occur when battery-based systems change energy from one form to another, for example mechanical to AC, to DC, to chemical, and back again. Additionally, it overcomes environmental issues regarding end-of-life disposal of batteries.”

The company has also announced that it will reveal two new technologies for high-efficiency variable drives, using developments associated with its variable supercharging technology but adapted for alternative uses.