Propane emerges as power-source solution for portable chippers

Diesel has dominated the wood chipper market for decades, but the development of emission standards for new off-road diesel engines has forced the tree care industry to explore and develop alternative fuel equipment over the last few years.

Gasoline has risen as the top alternative. Chipper manufacturers have unveiled gas-powered options in the 12-, 15- and 18-inch classes, and a number of tree care service providers have taken to these models. But propane has a presence in the market, as well. Manufacturers such as Morbark and Vermeer currently offer models that allow the user to switch between propane and gasoline.

The tree care industry hasn’t fully wrapped its arms around propane yet, but a time may come when it does.

“Our industry just hasn’t made the leap,” says Brett Bartels, a Vermeer engineer. “[Propane] is a tool in the toolbox. It’s just a matter of whether [tree care producers] choose to use that tool or not.”

Propane’s role

The Propane Education & Research Council (PERC) has voiced its interest in pressing further into the tree care market with chippers. Propane’s current availability in the market is through cylinder exchange, but PERC is exploring opportunities for OEM propane engines that operators could fill from a refueling dispenser.

“We’ve spent the last year really trying to find the engines worldwide that made sense,” says Tucker Perkins, PERC’s chief business development officer, in a November 2015 interview.

Propane is a natural fit for the tree care industry, Perkins argues.

“Tree care can take on anything from cutting down trees to doing good things with trees, but a lot of people tend to view cutting down trees as anti-green,” he says. “If you migrate from gasoline or diesel to propane fuel, a couple things happen automatically: You reduce your carbon footprint and change your image because you can talk about reduced emissions.”

The complexities of Tier 4 diesel technology present a particular opportunity for alternative fuels like propane, Perkins adds.

“It’s hard to get diesel clean enough to burn properly in these Tier 4 engines,” he says. “For diesel to better [its standing], there would have to be a radical change in the technology of the engine. That doesn’t appear to be happening. There’s complex filtration and complex equipment.”

Jay Sunderman, strategic business unit manager of tree care/rental and landscape at Vermeer, sees potential for propane to gain momentum with chippers. Still, a number of details related to fuel access must first be ironed out if tree care producers are to switch.

“In regard to LPG, we’ve made our system so there are removable 33-pound tanks that are typical to what’s mounted on a forklift truck,” Sunderman says. “It’s readily changeable, but you still need to have a source for the tanks and set up that distribution versus filling up at a pump. Some infrastructure needs to be put in place, and relationships need to be made between the user and propane supplier to make it viable.”

Morbark has had some interest in its gasoline/LP gas 12- and 15-inch chippers. But Casey Gross, a tree care product sales manager, points out many of the same obstacles for propane.

“We’ve built a handful of propane chippers already because it’s really a slight modification to the engine itself, and we just have to install propane tanks and the lines to run to the engine,” he says. “The downfall to that is having the tanks available. You have to have multiple tanks to keep running long term.”

Still, Morbark has shown that propane offers the lowest operating costs – at least for two of its Beever chippers the company compares across diesel, gasoline and propane. Morbark compares the Beever M12R, which features a 74-horsepower Tier 4 diesel engine or an 89-horsepower gasoline/LP gas engine. The company concludes that use of a diesel engine costs $24.47 per hour to operate over 2,500 hours. Gasoline ($22.14 per hour) and LP gas ($21.28 per hour) are presented as less-expensive options.

The competition

Propane isn’t the first alternative to diesel, though. Gasoline has captured the majority of the gallons diesel has lost in recent years.
“Before emission regulations were in place, 98 percent of all chippers were on diesel,” Gross explains. “Now, with the new emission standards and the new tier of engines, 25 to 30 percent are leaning toward gas engines. The Tier 4 emissions regulations are driving the change and driving customers to look at alternatives.”

Specifically, costs are driving the shift from diesel in certain chipper classes, says J.R. Bowling, vice president at chipper manufacturer Rayco Manufacturing.

“The cost of a Tier 4 Final diesel engine in the 75 to 173-horsepower range is prohibitive compared with a gas engine in the same class, he says. Plus, the cost of gas in recent months has been particularly rewarding for those with gas-powered equipment.

“If a [tree care service provider] is paying on-road diesel prices, those have been higher than gasoline for some time now,” Bowling says.
Still, propane has advantages over gasoline, Perkins argues.

“Our emissions profile is better,” he says. “We can still be cost-competitive, or cheaper. Gasoline is a competitive threat if it’s used for a device that doesn’t operate a lot. You might use it a day a week, but those aren’t really technologies we want to capture anyway. We’re looking for applications being used eight to 20 hours a day, five to seven days a week.”

In addition to gasoline, electricity may soon carve out a competitive space for wood-processing equipment.

“You’re going to see more manufacturers looking at alternatives such as electric,” Gross says. “You’re seeing more electric cars and charging stations. We’re actively pursuing the electric market right now.”

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The next frontier

Considering the cost savings propane offers, the Propane Education & Research Council (PERC) is exploring other propane engine opportunities related to portable processing equipment.

“We’re taking a fresh look at where any diesel or gasoline engine is in place,” says Tucker Perkins, PERC’s chief business development officer. “A propane-fueled engine probably has market opportunity anywhere an engine is consuming diesel fuel or gasoline.”

This includes higher-horsepower machines such as horizontal grinders, or crushers used in the aggregates and recycling industries.

“We’re ready to move to bigger devices like tub grinders,” Perkins says. “We’re looking for engines with the same operating characteristics of the diesel [engines] they’re replacing. These are high-efficiency, very durable engines that have the same kind of durability profile of the diesel they’re replacing.”