FIRST DOUBLEDECKER BUS WITH BAE HYBRID SYSTEM FOR LONDON
A red London bus with a BAE Systems hybrid electric drive train has been delivered to Transport for London and Metrobus, one of the UK capital’s principal bus operators. The bus, a double-deck model built by Britain’s Alexander Dennis Limited (ADL), is among 17 hybrid units built by ADL and BAE Systems that will be evaluated in passenger service starting later this year.
Delivery of the bus marks the introduction of BAE Systems’ HybriDrive propulsion technology to the European market. The diesel-electric drive system is already in use on more than 1,500 buses in North American cities.
The HybriDrive system is used by transit agencies in New York, San Francisco, Houston, Toronto, and Ottawa. The system, which reduces emissions and fuel consumption while meeting the durability requirements of demanding urban transit operations, consists of a generator, an electric motor, and an energy storage system managed by computerised controls. A diesel engine that turns the generator operates independent of the electric drive motor, allowing it to run at nearly consistent speed for optimum efficiency.
The system uses no mechanical transmission, a major maintenance item on traditional diesel buses, and features a regenerative braking system that produces electric power while reducing wear on the buses’ conventional friction brakes.
The bus delivered to the London fleet uses a lithium-ion energy storage system that increases battery life and reduces vehicle weight compared to previous hybrid designs. Lower weight further improves fuel economy and cuts emissions, and the battery system is self-monitoring and easy to service for further savings in maintenance costs.