NASHVILLE, Tenn. — Hybrid commercial vehicles have lost some luster over the past couple years, as natural gas has stolen the headlines and established itself as the alternative fuel of choice among many fleets looking to reduce their fuel costs and environmental footprints.
However, a panel of medium-duty truck operators speaking at the Technology & Maintenance Council meetings agreed that hybrids can still provide significant fuel savings, when deployed into the right duty cycles.
Ronald Kleintop, who manages the Miami Dade County fleet in Florida, said his municipality has been running hydraulic hybrid garbage trucks from Autocar. The hybrid powertrain was developed by Parker.
After running six trucks for three years, Kleintop said Miami saw a fuel savings of 20-25% initially, and as high as 56% on some routes.
Worries about downtime turned out to be unwarranted, Kleintop said, even though Parker deployed a team of engineers to the area to help support the trucks.
“What we found was, uptime was much better than we had with our diesels and we also found fuel economy kept getting better and better,” Kleintop said.
The municipality was impressed enough with the fuel savings to order another 62 trucks with the Parker Hybrid Drive System.
But even where the application is perfect for hydraulic hybrids and the trucks are surpassing the expected fuel savings, Kleintop said there’s pressure to move to compressed natural gas (CNG).
“We are under an order (from the city) where we can’t buy anything that’s not CNG and I have a real problem with that,” he said. “We have no facilities for maintenance or fuelling capability for CNG. I have a tough time with that because, when you find something that works, why do something else?”
When deploying hydraulic hybrid trucks, some driver training is required, Kleintop acknowledged.
“Until (drivers) learned how to operate the truck, it took longer for them to make their routes. Once they had the training, they made their routes 20-35 minutes faster (than with diesel trucks),” he said.
The hybrids, according to Kleintop, have been more reliable than their diesel counterparts and maintenance requirements were about the same. Some other benefits include quieter operation and quicker launches.
Tony Eiermann, fleet asset manager with Coca-Cola Refreshments, also voiced satisfaction with the performance of hybrid vehicles.
Nine per cent of its delivery fleet – some 738 vehicles – are hybrids. Coca-Cola is on a mission to reduce its fuel consumption by 15% by 2020, and for good reason; every 1% in fuel savings reduces Coke’s fuel consumption by 560,000 gallons per year. But while hybrids work well across many of Coca-Cola’s routes, Eirmann stressed there’s no single solution to greening the fleet.
He preached a holistic approach to alternative fuels, including hybrids and other alternatives, such as plug-in electric vehicles and natural gas.
He also pointed out hybrid vehicles don’t have to cost a lot more than diesels, if you take advantage of government grants.
Of Coca-Cola’s 738 hybrids, almost all were purchased through grant programs, which in many cases completely eliminated the cost premium associated with hybrid vehicles. Other technologies that are working well for Coke include natural gas and XL bolt-on hybrid systems.
The nice thing about hybridization, Eirmann noted, is that there’s no additional fuelling infrastructure required.
The first of Coca-Cola’s hybrids were put into service in 2007. They’re now out of warranty and Eirmann said the fleet is beginning to encounter some costly repairs.
“Some of those price tags (for repairs) are a bit expensive,” he said.
The New York City experience, delivered by Rocco DiRico of the City of New York Sanitation Department, emphasized just how varied results with hybrid vehicles can be, depending on technology type and duty cycle. New York deployed both hybrid-electric vehicles as well as hydraulic hybrids.
The hydraulic hybrids, sourced from a different supplier, delivered a disappointing 3.2% improvement in miles per gallon. The hybrid-electrics, on the other hand, showed a 22% improvement. DiRico agreed with Eirmann’s philosophy that there’s no single solution.
“None of them are a cure-all, fits-all,” he said. “You have to be diverse.”
Have your say
We won't publish or share your data