A new research project aims to provide regenerative braking capability with on-board mechanical energy storage for the first time on diesel commuter trains.
Due to start later this year, the project will see technology consultancy Ricardo join forces with fluid power expert Artemis Intelligent Power and rail systems business Bombardier Transportation. Additional funding will come from the government-backed Technology Strategy Board.
The system they are working on is intended for use on diesel-powered multiple units. It is conceived as a cost-effective solution that could be retrofitted to existing rolling stock as well as built into new rail vehicles, to achieve fuel savings of between 10 and 20 per cent.
To demonstrate a complete rail driveline, an Artemis Digital Displacement hydraulic pump-motor and a Ricardo Kinergy flywheel high energy density storage system will be coupled to a wheel-set supplied by Bombardier and will be tested on a dynamometer rig at Artemis’s facility in Midlothian, Scotland. If all goes well, a follow-up project will progress to an operating train.
The equipment from Ricardo and Artemis, together with Bombardier’s manufacturing and system integration expertise, will enable energy recovery and storage to be integrated into diesel trains for the first time. The system can be tailored to suit operating philosophies, such as adjusting the engine demand to operate closer to its optimum brake-specific fuel consumption, hence saving fuel and reducing carbon dioxide emissions.
Alternatively, stored energy could be used to augment the peak acceleration of the vehicle, which would increase the operational flexibility of older rolling stock. Trains that accelerate faster allow for increased network capacity, hence enabling more rapid recovery from delays and minimising consequential impacts across the network.
“While we are evaluating the Kinergy in a commercial bus application, this project will be the first to deploy this very promising mechanical energy storage technology in a rail application,” said Ricardo head of rail vehicle technology, Jim Buchanan.
Paul Roberts, UK head of Bombardier Transportation, said the project would help towards improving the long-term operational viability of legacy diesel fleets.