New International SuperTruck II Prototype Semi Gets an Impressive 16 MPG

Hybrid trucks like this one could make a big impact on freight-hauling emissions.

byNico DeMattia|
Trucks photo


Making long-haul trucking more efficient is one of the biggest challenges the automotive industry faces at the moment. While passenger cars can pretty easily be made more efficient, with downsized engines and electrification, making semi trucks efficient without sacrificing their abilities to haul massive loads isn't quite as easy. However, the new Navistar International SuperTruck II prototype takes a holistic approach to efficiency and gets an impressive 16 mpg.

In a passenger car, 16 mpg is pretty dismal. However, the typical semi truck gets anywhere between 5-7 mpg, so 16 mph is incredibly good.

The SuperTruck II is part of the Department of Energy's (DOE) SuperTruck program, which is meant to heavily reduce emissions and fuel consumption for on-road freight-hauling trucks. Navistar isn't he only company building trucks in this program but it might have the most efficient one. To make it so, Navistar developed a new hybrid powertrain, relied heavily on lightweight materials, improved rolling resistance, and focused on aerodynamics.

"The team concentrated its design on high-voltage electrification, utilizing hybrid technology on a path toward full electrification that has the potential to be commercialized in fully electric vehicles, and improve customers' total cost of ownership (TCO) and business operations," said Russ Zukouski, chief engineer of the Navistar SuperTruck program.

Not only is the shape of the cab incredibly aerodynamic for a semi-truck, Navistar also developed the box to be more aerodynamic than ever (it's the only OEM to make such a box). It's a lightweight box, made of composites, and it features an aerodynamic design, which includes aerodynamic underflow treatments. It also gets 6.7 kilowatt solar panels, which help its battery efficiency. All of that adds up to a 170 percent improvement in freight-ton efficiency (FTE), which is the amount of energy it requires to haul cargo.

There's also brake-thermal efficiency (BTE), which is how all engines' fuel-burning efficiency is measured. In most diesel engines, around half of its internal combustion energy is lost, due to heat and friction, giving them a BTE of anywhere between 40-45 percent. However, the SuperTruck II has a claimed BTE of 55.2 percent, which is one of the main reasons it can get 16 mpg.

Full electrification for mainstream semi trucks is still very far off. There are a few brands making electric semis, including Freightliner, Volvo, and Tesla, but they aren't used in widespread freight hauling just yet. Until we get to that point, improving the efficiency of internal combustion semis with hybrid powertrains and advanced aerodynamics is the way to go and this International SuperTruck II seems like a great next step, as long as it doesn't cost too much for fleets to buy.

Got tips? Send 'em to