Allison-Cummins hybrid gets CARB OK

Allison Transmission Holdings Inc. and Cummins Inc. today announced they have received annual certification from the California Air Resources Board (ARB) for model year 2021 Allison Hybrid 40/50 Electric Propulsion (H 40/50 EP) system paired with the Cummins B6.7 and L9 diesel engines.

Allison Transmission and Cummins have received 2021 approval for the Allison Hybrid 40/50 Electric Propulsion system.

Originally issued by CARB in 2014, the dual Executive Order (EO) is required to be reviewed for renewed eligibility on a model year basis. The Allison electric hybrid propulsion system and Cummins engine pairing is used in both straight and articulated transit buses as well as coaches.

In full operation since 2003, the Allison H 40/50 EP has demonstrated reduced emissions, quieter operation and improved fuel economy – up to 25% over similar diesel buses, Allison said. Additionally, the H 40/50 EP’s regenerative braking system converts the vehicle’s kinetic energy to stored electric energy when decelerating or stopping, which can significantly extend the brake change interval by as much as 350%, reducing maintenance costs.

“We appreciate ARB’s continued renewal,” said Barbara Chance, director of Mobile Source Regulatory Compliance for Allison Transmission. “Allison was the first electric hybrid propulsion system to be certified in California for transit buses and coaches. We are particularly excited to now turn our collaborative focus with ARB on 2022 certification of our eGen Flex electric hybrid propulsion solution, which provides full EV capability for up to 10 miles.”

The B6.7 diesel used in the system is rated at 280 hp (209kW) while the L9 engine is rated at 330 hp (246kW) for the transit bus market.

“Cummins is pleased the Allison electric hybrid propulsion system has received 2021 ARB certification,” said Francisco Lagunas, general manager, North America Bus Business, Cummins Inc. “We believe the latest Cummins and Allison clean diesel power system will provide our bus customers an even more reliable and environmentally-friendly powertrain to help them be as successful as possible. For 2021, our latest generation of B6.7 and L9 engines are enhanced with improved fuel economy, and improved uptime, reducing overall costs for customers.”