IndyGo, in partnership with Allison Transmission, GILLIG, and Cummins, announced the first buses equipped with the Allison eGen Flex electric hybrid propulsion system have arrived at the agency.

The eGen Flex is the next generation of Allison’s proven H 40 EP electric hybrid propulsion system, which has been operating in select IndyGo buses since 2004. In addition to the benefits provided by the H 40 EP, such as improving fuel consumption by up to 25% versus a conventional diesel bus, the eGen Flex provides revolutionary capabilities, which include full electrification range.

“IndyGo’s continued collaboration with Allison represents our joint mission and commitment to reduce our carbon footprint in the Indianapolis community,” said IndyGo President/CEO Inez Evans. “The delivery of the GILLIG buses equipped with the eGen Flex technology represents the next step in our efforts to reduce our dependence on fossil fuels, enhance quality of life for residents and do our part to protect the environment.”

The eGen Flex, which is paired with the Cummins B6.7 engine in GILLIG buses, is capable of traveling in electric-only mode for up to 10 consecutive miles or 50 minutes before converting back to hybrid propulsion. This electric-only mode can be utilized multiple times per route and per day. The eGen Flex can operate up to 50% of the time in engine off mode while still powering auxiliary systems like air conditioning and heat at optimal efficiency. The system’s electric-only mode is activated through geofencing technology and eliminates engine emissions and noise while loading and unloading passengers in dense pedestrian areas, zero-emission zones, and at Indianapolis’ public transportation hub the Julia M. Carson Transit Center.

IndyGo will be the first transit system to operate GILLIG buses equipped with the Allison eGen Flex and Cummins B6.7 engine pairing.