Series-E & ER: Electric hybrid propulsion

More than 10,000 of our electric hybrid systems are in operation around the globe, providing both electric power for vehicle accessories and electric propulsion for zero emission travel. Depending on a transit operator’s needs, we offer two electric hybrid solutions to choose from—Series-E and Series-ER. Both systems operate on all electric power—all the bus accessories, such as air conditioning, power steering, and air compressors are powered with our electronics and our electric motors drive the wheels. Further, both systems use the same components, the only difference is their energy storage systems.

With Series-E, all bus accessories can be powered by our electric system and our stop/start function can be enabled to decrease idling at stops. Further the engine can be shut-off for short distances, such as in and around a bus depot to decrease emissions. For those looking for more engine off time, Series-ER is used. With Series-ER, an operator can operate the bus 35% of the time with the engine off to increase opportunities for low and zero emission travel. Recently, Nashville’s WeGo Public Transit set up zero-emission zones using Series-ER with geofencing technology. They are using Series-ER to provide zero emission zones in their high traffic downtown area, and near hospitals and schools. Nashville appreciates the ability to operate electric drive buses without needing to install charging infrastructure or plan time for the bus to stop and charge. Since our system has an onboard generator charging infrastructure is not needed nor a plan to stop and charge. With Series-ER, once the bus drives out of the geofenced area, the bus will automatically switch back into electric-hybrid mode. Take a look at a video description of the product told by WeGo Public Transit.