Hyliion has developed an add-on hybrid system for tractor-trailers that will reduce fuel consumption by about 30% with a return on investment of less than one year, according to Thomas Healy, CEO and founder of the Pittsburgh, PA-based startup.

“What makes our system unique is that we solely focus on the trailer,” Healy said to Off-Highway Engineering. “We replace the existing rear axle assembly under the trailer with an electric propulsion system. So now what happens is when the vehicle is slowing down or going downhill, we’re able to capture all that wasted energy and store it in the battery pack on the trailer.”

When the truck accelerates or starts an uphill stretch, the system drives the rear tires on the trailer. “So the diesel engine in the truck doesn't have to work as hard, there's not as much load it needs to pull,” he said.

The intelligent electric drive axle system was recently awarded the grand prize in the 2016 “Create the Future” Design Contest produced by Tech Briefs Media Group, beating out more than 1100 product ideas from 71 countries. The contest was co-sponsored by COMSOL and Mouser Electronics, with Analog Devices and Intel serving as supporting sponsors.

(Additional category winners in Aerospace & Defense, Automotive, Electronics and more can be viewed at www.createthefuturecontest.com.)

Most conventional hybrid strategies integrate an electric motor into the drivetrain of the truck. “Since we don’t integrate right into the drivetrain, you can keep all that existing equipment and not make any modifications to it. We’re getting the benefits of a hybrid system but with an add-on solution,” Healy said.

Essentially, Hyliion is turning a passive axle into a drive axle. “It’s like taking one of the axles off the truck and putting it on the trailer,” he explained. “So now we have a drive axle that we can apply positive and negative torque, with an electric motor connected to the axle.” The electric motor is connected to a control system with a lithium-based battery pack.

The company leverages existing components to help bring the product to market faster. For example, the axle is a production component that’s already been tested and has the weight rating certifications needed to travel over the road.

The system can be installed on nearly every trailer type in less than one hour, the company claims, without changing trailer height or length.

The electric drive axle system is categorized as an auxiliary power unit (APU), capable of powering auxiliaries overnight such as electronics and air-conditioning. Even though the system adds about 500 lb (227 kg) to a tractor-trailer, “the government in most states allows you to carry anywhere from 400-450 extra pounds of payload if you’re running an APU. So it’s really not netting much of a loss of cargo that you can carry,” Healy said.

The electric drive axle doesn’t have any data communication with the truck. The system’s sensors are able to determine when to apply power and when to capture energy. It does have cellular communication and satellite, so the vehicle can be tracked.

“From a fleet standpoint, you can look at how fast your trailers are moving and where they’re located, and we can do things like tell you how much load is in the trailer,” Healy said.

Information is available to the driver via a mobile dashboard application. The driver has the ability to turn the system on and off.

Final Phase 2 greenhouse gas standards, affecting model year 2021-2027 medium- and heavy-duty on-highway vehicles, mandate for the first time that fuel-saving technology be employed on the trailer in addition to the truck. (See http://articles.sae.org/15073/.)

“Our single product is able to propel you above those mandated requirements,” said Healy. “We see it being a perfect solution for this new Phase 2 mandate that’s coming out. From a timing standpoint, it couldn’t be better.”

Hyliion currently has six trucks running with its system for internal testing and validation. “The next phase is we’ve got over 30 fleets that have signed into our pilot program that we’re going to start delivering units to before the end of this year,” he said.

In-house production of the electric drive axle system is expected to begin Q1 2017, and the company is lining up outsourced production for higher volumes in Q2 2017.

“Our next big milestone is really setting up the production,” Healy shared. “There is a lot of demand in the industry for a product like this...How can we manage all the production and supply chain so that we can grow at a very fast pace and get our partners alongside us to grow at the same rate? Our mindset is scaling up production as fast as possible to as high a volume as possible.”