While it seems just about every type of passenger car has hybrid variants, heavy duty vehicles are getting into it as well, as there are a number of hybrid semi-trucks in development. Heavy duty vehicles are far from the biggest polluters, but they are major gas guzzlers to be sure.
Freightliner unveils Super Truck hybrid semi
Hybrid drive technology is actually very old, having been invented about a century ago by Dr. Ferdinand Porsche, but modern car manufacturers are jumping into it; even hybrid semi-trucks are on the horizon. In fact, Freightliner has just unveiled a new hybrid semi prototype dubbed the Freightliner Super Truck. Various sites are reporting it, but Freightliner has their own site.
The truck is only a concept for the moment, but as what engineers call a design study, it’s quite a feat. Aerodynamic improvements, intelligent (computer enhanced) transmission and steering systems, and an electric drive (and battery) system are added, as well as a lightweight chassis, among other refinements. A kinetic energy recovery system is also included to use the waste heat from braking to power accessories and the hybrid drive. The base power train is a 10.7-liter engine producing under 400 horsepower but 1,400 foot-pounds of torque.
Freightliner put the truck to the test, hitching a 65,000-pound load and hauling it 312 miles at an average 65 miles per hour, returning 12.2 miles per gallon. Granted, that’s appalling compared to even a Ford F-150 these days, but it’s double standard fuel economy for tractor trailers. The truck will be on the semi-truck show circuit this year.
The federal government assisted with development costs, matching costs with Freightliner – and parent company Daimler – with a Department of Energy grant.
Even Walmart is in on it
The Freightliner Super Truck isn’t the first of the hybrid semi-trucks; another concept debuted in 2014, which was entirely Walmart’s idea. Walmart worked in conjunction with Peterbilt, Great Dane Trailers and Capstone Turbine to develop the Walmart Advanced Vehicle Experience – or WAVE – to see how Wally World could save a few bucks on shipping costs.
Unlike traditional hybrids, which employ a standard engine along with battery systems and electric motors, the WAVE used a turbine engine, which was capable of running on multiple fuels, including gasoline, diesel and biofuels. Along with the turbine/electric drivetrain, the WAVE also had advanced aerodynamics, giving the truck a parrot fish-like appearance, along with a McLaren F1-style (driver in the middle) seating arrangement.
Walmart didn’t make fuel economy figures available, but according to Car and Driver, drag was reduced by 20 percent and by using carbon fiber for the cab, the WAVE truck achieved a two-ton (4,000-pound)reduction in weight.
Still awhile before one is east bound and down
Hybrid semi-trucks are not ready to start hauling. The WAVE and the Super Truck were just concepts; either truck is years from production. Whether the technology is adoptable is another question to be settled. Semi-trucks are by nature commercial vehicles and the gas savings may never pay for the increased base price of the vehicle.
Also, the reduced emissions will hardly save the planet. According to the Department of Transportation, the impact of freight trucks and other heavy vehicles on emissions is far from negligible, but it’s fairly small. Of all emissions of carbon dioxide and other greenhouse gases, transportation as a whole accounts for 28 percent of the total; heavy-duty vehicles account for less than 21 percent of all vehicles. (Passenger cars and trucks account for 63 percent.)
Power generation remains the single largest polluter, at 33 percent of all emissions, but it’s more politically expedient to go after the smaller fish.