Kenworth’s SuperTruck 2, unveiled at the Advanced Clean Transportation (ACT) Expo in Las Vegas, stands out as one of the event’s most innovative trucks. This project is a collaborative effort between the Department of Energy (DOE) and Paccar, developed over six years, leaning into diesel fuel technology to power its futuristic design concept.
Engineering for Efficiency
The truck’s aerodynamic design is significantly enhanced by the strategic location of the powertrain, fitting between the frame rails. This setup allows the engine to be lowered and placed behind the front axle. Kenworth General Manager Jim Walenczak emphasized the goal of achieving a 100% improvement in freight efficiency compared to the 2009 Kenworth T660, renowned for its fuel efficiency.
Remarkably, Kenworth surpassed this target, achieving a 136% efficiency improvement by enhancing fuel economy to 12.8 mpg and reducing the combination weight by over 7,000 pounds. This allows for more payload capacity with an ultra-fuel-efficient tractor-trailer combination.
Advanced Powertrain and Hybrid Systems
The SuperTruck 2 is powered by a Paccar MX-11 engine rated at 440 hp, paired with a TX-12 automated transmission. It features a 48-volt electric generator, creating a mild hybrid system supported by next-generation lithium-ion batteries recharged through regenerative braking. This system powers electric fans, steering, coolant, and HVAC pumps, which were previously mechanically driven. Additionally, the hybrid system provides an overnight engine-off solution and powers the exhaust heater in the close-coupled after-treatment system, meeting CARB 2027 ultra-low NOx compliance standards.
The 48-volt hybrid auxiliaries and energy recovery system boost the MX-11 engine’s efficiency to 55.7%, compared to the 47% efficiency of traditional modern diesel engines. Maarten Meijer, Paccar’s senior engineering manager for advanced technology, highlighted this as a significant leap forward, indicating a potential 10% fuel efficiency improvement if this engine were to enter production.
Innovative Design and Aerodynamics
Kenworth’s SuperTruck 2 features a unique “center driver” cab and a newly designed sleeper compartment. The aerodynamic design benefits from the reverse-splayed chassis, which narrows the front of the truck and encloses the wheels within the bodywork. The entire hood and chassis fairings are mounted directly to the cab, moving as a single unit. A variable suspension system customizes ride height to optimize aerodynamics, raising the truck over rough roads and lowering it on smoother interstates.
A parabolic windshield improves visibility and smooths airflow, while the elimination of physical mirrors reduces drag. Instead, an integrated digital mirror system enhances rearview monitoring, trailer tracking, and night vision capabilities, as seen in the Kenworth T680 models. These features contribute to a 48% reduction in drag compared to Kenworth’s baseline truck.
Weight Reduction and Fuel Efficiency
The SuperTruck 2’s combination weighs in at 26,100 pounds, 7,100 pounds lighter than a typical tractor-trailer configuration. The tractor alone saves 4,100 pounds, and the trailer an additional 3,000 pounds. New concept tires, weighing 355 pounds less than current market alternatives, also feature extremely low rolling resistance, scoring 4.2 on the CRR scale versus 5.0 for typical high-efficiency tires. The improved powertrain’s fuel efficiency allowed for a smaller 80-gallon fuel tank, reducing overall weight without sacrificing range.
Driver Comfort and Practicality
Kenworth SuperTruck 2 designers prioritized driver comfort, incorporating a unique sleeper berth with a fold-down bed over a sofa, creating separate sleeping and sitting areas. A rotating tabletop allows drivers to eat or work without needing to clear the surface when moving the table.
Kenworth’s SuperTruck 2 represents a significant advancement in trucking technology, combining cutting-edge aerodynamics, a highly efficient hybrid powertrain, and innovative design elements to set new standards in fuel efficiency and driver comfort. This trailblazing vehicle not only showcases what is possible in modern trucking but also sets a high bar for future developments in the industry.
Source: Commercial Carrier Journal
Photos: Kenworth
