Heavy Duty Trucking, September 2018

HDT SEPTEMBER 2018 26 WWW TRUCKINGINFO COM Behind the wheel of Peterbilts electric Model 579 daycab Jack Roberts Senior Editor jroberts@ truckinginfo com Peterbilt wants to stake out leadership positions with any viable new technology but is not interested in forcing anything on anybody until they are interested Jack has become known for his reporting on advanced technology such as intelligent drivetrains advanced driver assist systems autonomous vehicle technology truck platooning and alternative fuels He can be reached at jroberts@ truckinginfo com or 310 533 2521 drove a demonstration model of an electric Model 579 for a brief evaluation run through the heart of Silicon Valley during a recent visit to the Paccar Innovation Center in Sunnyvale California The truck is being developed in partnership with TransPower an electric vehicle tech startup in the area that is looking to become a Tier 1 supplier of vehicle electrification components and technology for the trucking industry Peterbilt and TransPower have been working together on electrification projects since 2015 Matthew Vito a systems engineer with TransPower was on hand to answer questions From the exterior there are only a few clues that youre not dealing with a conventional diesel powered Model 579 tractor chiefly the eight pack battery assemblies on the frame behind the cab These 44 kW battery packs give the truck up to 250 miles of range in highway driving conditions Vito said each individual battery pack weighs approximately 800 lbs I was curious to know what was sitting under the hood in place of a conventional diesel engine and Vito was happy to show me the power inverter and converter system that reside in that space on this truck This is essentially a sophisticated power management system that collects stores and distributes electric power as needed during driving operations both from the battery packs and from the trucks kinetic energy braking system which converts forward inertia into energy and captures it for future use Vito said the system is remarkably efficient in terms of both range and recharging capability needing only four hours connected to TransPowers proprietary charging system to retain a full change Climbing into the cab the first thing I noticed was an Eaton UltraShift control box mounted to the dash I was under the impression that electric vehicles dont need conventional transmissions to operate And they dont But that doesnt mean they cant take advantage of their benefits Vito explained that most electric trucks use massive sized electric motors with continuous torque curves just like on a golf cart Peterbilts use of an automated manual transmission means TransPower is able to fit the truck with two much smaller electric motors in sequence These electric motors have a much shorter torque curve than the big motors But thats where the transmission comes into play taking the torque the two motors produce and turning it into usable power This saves on space and weight as well Vito noted The electric Model 579 shifts at the same speed and torque points a diesel engine would so the overall feel while youre driving is extremely familiar In fact if you had someone playing diesel engine sounds over the truck stereo Id be willing to bet that more than a few experienced drivers wouldnt know right away that they were actually driving a truck equipped with an electric drivetrain The first giveaway however would probably be when they put their foot in the throttle and felt the truck take off from a dead stop Granted we were running bobtail on our little route through Sunnyvale But the acceleration this trucks electric FUTURE FLEET I One of the more interesting things about Peterbilts electric Model 579 demonstrator truck is that it uses a conventional Eaton automated manual transmission as part of the electric drivetrain PHOTO JACK ROBERTS