Kenworth has delivered two prototype Kenworth T680 tractors – equipped with a series hybrid-electric propulsion system – to Total Transportation Systems in Southern California. TTSI is a drayage, warehouse and transportation company based in Rancho Dominguez.

The two T680 day cab tractors are Kenworth’s second-generation, range-extended electric trucks. They are able to run in zero emissions mode on batteries for 30 miles, and recharge those batteries while driving using a generator powered by a near-zero emissions natural gas engine.

The trucks were built under a project funded by California Climate Investments and the Greenhouse Gas Reduction Fund, and administered through the California Air Resources Board and South Coast Air Quality Management District.

“These zero emissions-capable Kenworth T680 range-extended electric vehicles were developed to explore and evaluate potential alternatives to diesel power for Class 8 commercial trucks, and to broaden Kenworth’s experience with electrified powertrains. They offer an excellent solution for local clean air regulations in drayage and regional applications,” said Brian Lindgren, Kenworth research and development director, in a press release.

The trucks will serve the ports of Los Angeles and Long Beach.

The two Kenworth T680 hybrid-electric vehicles use the Cummins Westport L9N Near Zero emission engine fueled by compressed natural gas driving a generator to extend the truck’s battery range. They use lithium-ion batteries to achieve the zero-emissions range and to supplement power from the generator when climbing grades.

The system’s energy management and control capabilities ensure that energy generated by the engine and regenerative braking system is appropriately applied through the electric motor, resulting in lower fuel consumption, Kenworth officials said.

Recent tests comparing the Range Extended Electric truck to a truck using a conventional natural gas powertrain showed a 23% improvement in fuel economy and an 18% reduction in CO₂ emissions, company officials said.