New Super Truck Can Haul Freight and Slash Fuel Costs

US – Volvo Trucks North America this week showed off its SuperTruck demonstrator, a vehicle designed to slash fuel consumption when laden with freight. The truck draws on all the obvious areas where savings are possible, advanced aerodynamics, vehicle and powertrain technologies, resulting in a freight efficiency improvement of 88%, exceeding the 50% improvement goal set by the original US Department of Energy (DOE) programme.

The concept employs a wide variety of technologies including an ultra-light aluminium frame and highly advanced 425 horsepower 11-litre proprietary engine and top-of-cab solar panels powering its battery and interior lights. These innovations resulted in the tractor trailer combination boosting fuel efficiency by 70% to over 12 miles per gallon, a figure inconceivable to road haulage operators just a few years ago for a rig of this type. Meanwhile in road tests powertrain brake thermal efficiency reached 50%.

A key part of the overall efficiency gain is that downsized 11-litre Volvo engine, featuring advanced fuel injection, cooling, oil and turbo-charging systems, as well as new ‘wave’ pistons together with other improvements. The SuperTruck powertrain includes a complex Rankine waste-heat recovery system, which converts heat normally wasted in exhaust into torque, boosting fuel economy by helping to power the vehicle.

While not every technology demonstrated in the Volvo SuperTruck will be commercialised, three of the engine advancements developed through SuperTruck research, the wave piston, turbo compounding system and common rail fuel injection system, are already featured in Volvo Trucks’ 2017 engine line-up. Likewise, a number of SuperTruck-derived aerodynamic improvements, like flared chassis fairings improving air flow around the drive wheels, a redesigned bumper and turbulence-reducing deflectors, can be found on today’s Volvo VNL tractors. Göran Nyberg, president of Volvo Trucks North America was clearly impressed by his team’s achievements saying:

“With the support of DOE’s SuperTruck program, Volvo Trucks has presented an exciting vision of trucking’s future. Even more impressive is the fact that these tremendous gains were made against a base model Volvo that already in 2009 averaged 7 miles per gallon. Our work through this programme is paying dividends for today’s customers through the SuperTruck innovations we’ve already integrated into our products”

The original SuperTruck programme was a five-year DOE research and development initiative to improve freight efficiency, meaning more payload carried while cutting fuel used by 50% compared to 2009 base model trucks. The DOE recently selected the Volvo Group to participate in DOE’s SuperTruck II program, which will target a 100% improvement on a tonne-mile-per-gallon basis, and a powertrain capable of 55% brake thermal efficiency.

Volvo’s aerodynamic SuperTruck has a shorter front end than conventional trucks on the road today, and the hood has a sharper downward slope. Lightweight fairings run the length of the tractor and trailer, and cameras have replaced rear view mirrors. Its redesigned chassis is made almost entirely of aluminium, which halved the chassis weight and contributed to an overall tractor-trailer weight reduction of 3,200 pounds.

An enhanced version of Volvo’s I-See, a new feature that memorizes thousands of routes travelled and uses that knowledge to optimise cruise speed and keep the I-shift automated manual transmission in the most fuel-efficient gear possible, was an integral part of the fuel efficiency gains seen during SuperTruck on-road testing. Volvo used computer-aided engineering to reimagine nearly every part of the tractor and trailer without costly prototyping. While the VNL ‘body in white’ was mostly maintained in order to save time and ensure structural integrity, everything else, including the front end, the cab exterior pieces, the chassis fairing and the roof, were completely redesigned to maximize the aerodynamics of the tractor-trailer combination.

Not every idea made it to the concept vehicle. Working with suppliers and academic partners, the team explored the performance and safety of a number of lightweight materials. While some of these, like recycled carbon fibre, were not used in the SuperTruck, the knowledge gained in material science will be applied to future programmes. Pascal Amar, principal investigator for the project observed:

“The order of magnitude efficiency leap achieved by our SuperTruck is a testament to the outstanding work done by our team and our partners. We started by rethinking everything, and we discovered that with every layer you peel back, you uncover new opportunities.”