MT. VERNON, WA. As editors lined up to take Kenworth Truck Co.’s new hybrid-electric T680 Zero Emission Cargo Transport (ZECT) tractor for a spin around the test track here at the PACCAR Technical Center – a vehicle officially dubbed a “customer demonstration prototype field test truck” – the issue on most everyone’s minds is whether this vehicle represents the future of commercial vehicle propulsion technology.
The answer is both “yes” and “no,” according to Stephan Olsen, Kenworth’s director of product planning.
“We think we’re going to need a variety of technologies in the future,” he explained at a press event here. “The point of all of our [alternative power] research is that Kenworth needs to be prepared; there is no one single ‘silver bullet.’ We will need multiple technologies, which is why we are researching all of these options: fuel cells, hybrid electric, and natural gas. That way we will have a solution in place.”
Based on a daycab T680 tractor model, the ZECT is a hybrid-electric truck that uses 2,000-lbs. worth of lithium-ion batteries to power its dual-rotor electric motor; a motor that can generate up to 560 hp, which Olsen noted makes it capable of carrying the “legal gross combination vehicle weight” or GCVW of a Class 8 tractor.
“Our testing shows that this truck performs equally as well, if not better than, current diesel trucks on the market,” he said. “There is a lot of promise, and we see the day where Kenworth’s zero and near-zero emission trucks could be a common sight in regional operations. [That is why] Kenworth is heavily focused on the evaluation and development of both zero and near-zero emission solutions for the trucking industry.”
The $7 million T680 ZECT tractor tested by editors pulled a fully-loaded trailer that pushed its total GCVW up to 78,980 lbs. Engineers, however, cut back the output of the vehicle’s electric motor from 420 kilowatts (kW) to 300 kW or around 400 hp as it continues to test the shifting algorithms programmed into the truck’s 4-speed automated gearbox.
Brian Lindgren, Kenworth’s research and development manager, noted that there are six hydrogen storage tanks on board the T680 ZECT, stacked in a compartment built onto the back of the tractor’s cab. That hydrogen, when flowed through the fuel cell located under the hood where the diesel engine usually resides, generates electricity to keep the truck’s 2,000 lb. lithium-ion battery pack fully charged. The addition of the fuel cell gives the truck approximately 150 miles worth of range, Lindgren noted.
“We do not see this as an over-the-road solution,” he added. “We see it as a drayage and regional haul truck.”
A comparable T680 diesel-powered daycab tractor weighs in at 16,000 lbs.; the ZECT, however, weighs 22,000 lbs. due to the 2,000 lbs. battery pack, heating/cooling system for battery protection, hydrogen storage tanks, etc. “We have added about 6,000 lbs. to this truck compared to a diesel model, but that will be coming down,” said Lindgren. “It could drop by as much as half in the next five years.”
The T680 ZECT will spend another month to a month and a half at the PACCAR Technical Center before being placed into “real-world” freight hauling service at the ports of Long Beach and Los Angeles in Southern California, he said.
Olsen also noted that Kenworth is busily working on another alternative fuel project that is about a month behind the ZECT in development: the Hybrid Electric Cargo Transport or “HECT.” Using Cummins ISL 9-liter Cummins Westport compressed natural gas (CNG) engine, it, too, will be paired with a battery-driven propulsion system.
“It will operate at about 290 hp and will offer more range than a fuel-cell hybrid,” he explained. “Cost wise, CNG will be better. But if you need to be truly 100% zero emissions all the time, natural gas won’t get you there.”
By contrast, the only tailpipe emission from a fuel cell-powered electric truck is just water vapor, Olsen noted.
Kenworth is also planning to unveil a new “near zero” natural gas engine option in April via the deployment of the Cummins Westport ISX 12G.