Loud, bulky gas generators are the source of electricity for U.S. troops deployed in some areas around the world, but new units developed at the Office of Naval Research could reduce fuel consumption and make deployment easier for troops.
When tested recently, the Solid-Oxide Fuel Cell Tactical Electrical Power Unit cut the amount of fuel that a typical, 10-kilowatt diesel generator uses by 44 percent. A more fuel efficient generator means troops have less re-supply fuel to carry around — and fuel convoys often give away field positions to the enemy.
The new units are quieter too, said Don Hoffman, program officer at the Office of Naval Research Sea Warfare and Weapons department, during an interview on In Depth with Francis Rose. The diesel units DoD normally deploys are similar to home generators, but cooling units in the new fuel cell generators now produce noise levels similar to the hum of a refrigerator.
DoD is “at the tipping point to start packaging and deploying these,” said Jack Taylor, associate director of ground and sea platforms at the Office of the Assistant Secretary of Defense for Research and Engineering, in an ONR release.
There’s still more work left to do on fuel cell generator before it can be deployed on a large scale. After a demonstration at Aberdeen Proving Ground in June, the unit scored a technology readiness level of five. Based on the initial test, Hoffman said the fuel cell generator shows potential.
“Getting it out in large numbers, there’s a lot of factors associated with that,” Hoffman said. “Things like growth of the commercial industry to support deployed numbers or the increase of manufacturing capability improvement and materials. It goes along the same development path we walk through with our ship or gas turbines very early on.”
A fuel cell is an electro-chemical power system that operates like an engine. Solid-oxide fuel cells convert oxygen and hydrogen into electricity. The generator breaks down logistics military fuels — like JP-8 — in a complete fuel system. The key to the fuel cell unit, Hoffman said, is that all of this can be done with a small and portable unit.
“Fuel cells stacks have been around for a long time, but the breakthrough has been how to compile or how to generate a complete fuel cell system,” he said. “It’s how to do that in a very compact and efficient manner — so how to get it in the same package size and weight as a traditional generator and so it also produces the same power quality output.”
While the noise levels, less fuel consumption and logistics factors are obvious benefits, Hoffman said the solid oxide model takes a longer time to power up than a traditional diesel generator. Because a fuel cell generator needs to reach a certain temperature, the start-up process could take anywhere between 15 to 30 minutes, depending on the unit’s size. A gas generator typically takes a couple minutes to turn on, Hoffman said.
Though the unit tested well during the initial demonstration, Hoffman said DoD and the Energy Department are looking to push fuel cells onto unmanned vehicles and ships, in addition to forward operating bases.
“From our standpoint, we’re looking at it from the effects of alternative fuel such as biofuels and how to best improve on the power density for these future advanced fuels coming down the road,” he said. “It worked out very well, as far as a successful demonstration. Hopefully, we see the progression of it as we go through more into maturing it and getting it deployed.”