Putting Theory Into Practice
As the project came closer to becoming a reality, the next step was to decide how and where the technology should be implemented. With the assistance of Abel Womack, UNFI reviewed its fleet of lift trucks to determine whether it should convert select trucks in an existing facility to hydrogen fuel cells, or take advantage of a planned new distribution center with all the trucks powered by the new technology.
The Sarasota distribution center, newly opened in 2007, quickly became the location of choice to have all its Raymond lift trucks converted to fuel cell power. Not only did it have enough equipment to justify the hydrogen fuel cell infrastructure, but it had a solid local service center in Raymond Handling Consultants. Making the decision even easier for UNFI was the receptiveness of Florida to helping to fund sustainable initiatives for businesses in the state.
“Florida is at the cutting edge of funding renewable energy initiatives,” Dziki says. “It really helped us to make the return on investment compelling so we could go ahead with the project.”
The Raymond lift trucks in UNFI’s Sarasota facility consisted of Model 7400 Reach-Fork trucks, Model 5500 orderpickers, Model 4200 stand-up counterbalanced lift trucks and Model 8400 end rider pallet trucks. Considerations needed to be made for the differences between lead-acid batteries and hydrogen fuel cells, including the size of the battery compartment; how the technology would withstand the temperatures of the Sarasota facility’s freezer, cooler and dry storage areas; and whether the fuel cell-powered lift trucks would perform to the same level as their battery-powered counterparts.
On electric lift trucks, battery compartments are designed specifically to accommodate the size and weight of batteries. Fuel cells are larger than lead-acid batteries, so Raymond engineers needed to ensure that the fuel cells would fit in the battery compartments and maintain the required counterweight for each truck.
Significant changes needed to be made to the orderpickers to create a larger battery compartment to accommodate the fuel cell. As a result, Raymond engineered the industry’s first hydrogen fuel cell-compatible orderpicker, which features a specially built 21-inch battery box to accommodate a hydrogen fuel cell.
Another consideration was how the hydrogen fuel cells would withstand multiple shifts in the colder temperatures of the facility’s freezer, cooler and dry storage areas. Raymond conducted extensive testing of the hydrogen fuel cell in cold temperatures at its Greene facility to ensure performance would not be affected. Raymond also conducted extensive testing on the hydrogen fuel cell-powered lift truck models included in UNFI’s fleet to ensure the performance would be as good, if not better, than battery-powered trucks.
Feedback from operators at the UNFI Sarasota facility has been very positive. Raymond’s research shows that, as a lead-acid battery is used over the course of a shift, the voltage drops and lift truck performance goes down. With hydrogen fuel cells, voltage delivered by the fuel cell remains constant until the fuel is depleted.
Mike Garstka, operations manager at UNFI, says operators are seeing 10 to 12 hours of continuous use on the pallet trucks.
“That’s a significant improvement compared with the five to seven hours of use we were seeing with the batteries,” Garstka adds.
Productivity also has increased because of the short time it takes to refuel the lift trucks, compared with changing a battery. In a high-use lift truck, lead-acid batteries typically only last one shift, and the batteries normally take one shift to charge and another to cool down. It also can take up to 20 minutes to remove and replace a battery.
In contrast, hydrogen fuel cells rapidly refuel in a couple of minutes, and a facility can install multiple fuel stations that feed from a central tank. “Our pallet truck operators are ecstatic they only need to fuel one time at the beginning of their shift,” Garstka says.