Allison Transmission will offer Allison’s eGen Flex electric hybrid propulsion system to Gillig, a US-based transit bus producer. The system enables full electric mode for up to 10 miles. In May 2020 Gillig announced that its first battery-electric bus model was under testing. The bus features a drivetrain provided by Cummins.

allison eGen Flex gillig

Allison eGen Flex hybrid system, a new deal in the US

Gillig has received their first order for Allison eGen Flex electric hybrid-equipped buses from IndyGo, the Indianapolis Transportation Corporation.

The Allison eGen Flex system is capable of improving fuel economy by up to 25 percent versus a conventional clean diesel bus, Allison points out, and has the ability to operate accessories such as air conditioning and electric heat at optimal efficiency with electric power. Moving these accessories to electric power reduces the strain on the engine, reducing fuel consumption and maintenance costs over the vehicle’s lifetime.

eGen Flex system: full electric mode for Gillig buses

The full EV capability of the eGen Flex propulsion system can also eliminate engine emissions and noise while loading and unloading passengers, and while operating in densely populated areas or depots using geo-fencing. The eGen Flex system offers full electric drive capability for up to 10 miles, depending upon duty cycle and accessory load demands.

Gillig buses with eGen Flex system: diesel engine as a range extender

“Gillig and Allison have partnered for nearly 50 years to provide the highest-quality buses for our customers and the people they serve,” said Bill Fay, Vice President of Sales at Gillig. “Our companies are demonstrating how American ingenuity is supporting safe and clean public transportation, and recycling tax dollars back into our communities.”

“Gillig and Allison have established a joint partnership dedicated to optimized integration and a mutual commitment to innovation,” said Rohan Barua, Vice President of Sales, North America at Allison. “We are excited to continue our history of innovation with Gillig through the launch of the eGen Flex propulsion system, which provides our mutual customers full electric operation with engine-off capability, without capital infrastructure investment in charging stations. Through this solution, Gillig and Allison are able to offer customers full EV capability, while maintaining a diesel engine for added flexibility, effectively serving as a bridge solution to EV. The diesel engine can serve as a range extender, when needed for longer routes or route flexibility due to unplanned congestion or construction on routes”.