When the diesel in one of Louis Ratto’s trash collection trucks blew, he took it as an opportunity. The CEO of the family-owned Ratto Group, which operates refuse and recycling companies in Marin and Sonoma Counties, north of San Francisco, had the truck towed to Wrightspeed in San Jose, Calif., and told its proprietor, Ian Wright, “Here you are. Go to it.”
“It” was converting the truck’s diesel-and-automatic-transmission powertrain to a turbine-electric, plug-in series hybrid, a heavy-duty version of the Wrightspeed Route truck now delivering packages for FedEx. The two met several years ago at a trade show in Long Beach where Wright had a Route in the ride-and-drive exercise. The truck intrigued Ratto.
“I had been looking at alternatives to diesel because it had become so expensive, and the air quality people in California don’t like diesel anyway,” he said. “I looked at the Parker hydraulic hybrid, but it had drawbacks, including that you still had a diesel engine. I looked at compressed natural gas, which a lot of the big [refuse] companies are running now, but found out there are some negatives with it,” including range and maintenance.
Landfill gas is free but it must be filtered, and natural gas filling stations are expensive. So Rotta kept looking.
“And then I saw this [the Wrightspeed turbine-electric] and said, ‘Hey, look at this. This is out of the box. This could work.”
He and Wright agreed to retrofit 17 Freightliner Condor trucks with Route HD powertrains. The blown diesel put a truck in Wright’s hands about six months ahead of schedule. He figures its conversion should be finished by the end of this year.
Each retrofit will cost about $200,000, which is $150,000 more than a natural-gas conversion but $300,000 less than buying a new diesel chassis set up with a Canadian-made Labrie automated-sidearm packer body, as Rotta prefers.
The conversion will breathe new life into the Condors. “They’re really pretty good trucks,” and though they’re no longer produced, he’s found sources for parts to keep them running through the “brutal” constant stopping and starting of a residential trash truck.
The turbine engine will make about 325 hp, Wright says, and can burn a variety of fuels, including diesel and natural gas. Because it’s a series hybrid, the turbine doesn’t directly propel the truck, but turns a generator to produce electricity that’s sent to lithium ion batteries that will store up to 78 kilowatt-hours. They power a pair of electric motors that drive through 4-speed gearboxes that replace the differentials on the rear tandem axles. The motors are each rated at 230 kilowatts and together could produce up to 1,000 hp and 40,000 lb-ft, Wright says. But they’ll be electronically limited “because the drivers would have too much fun with that.”
Motors become generators during braking, sending electricity to the batteries so the turbine works less, and reducing wear on foundation brakes. Plug-in capability will allow a truck to run up to 40 miles on grid power, and the turbine generator gives it unlimited range.
Wright says he’s gotten interest in the Route HD from large fleets and truck builders, “but it’s too soon to talk about it.”
Ratto believes the Route HD’s efficient powertrain could save 50% to 90% in fuel over a straight diesel powertrain. “I’m hoping to convert all 200 of my residential trucks,” he says. “And if this works out, it will take me off the radar that California has for diesels.”