The engines can work in tandem or solo, much of the bus interior operations (doors, lights, etc) are powered by the rechargeable battery, and this is all powered by the parallel hybrid system named I-SAM. This includes the combined start motor, the electric motor, the diesel motor, and a combined electric control unit which work with Volvo’s I-Shift gearbox. The technology is significant due to its efficiency and cost effectiveness.
Volvo’s success with the efficiency gained in the 7700 is the fact that the hybrid components used for this project were developed by Volvo for this project. In the past the effort has been to use outside parts and incorporate them in existing platforms. By avoiding this technique Volvo has created a truly effective hybrid bus.
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