At first listen, it’s like the truck is part of a silent film, but birds tweeting and leaves rustling validate the existence of sound.
This is what it’s like to hear the ZH2 hydrogen cell-powered demonstrator at work that GM and the U.S. Army’s Tank Automotive Research Development and Engineering Center developed together to inexpensively and rapidly bring the technology to soldiers for testing.
Stealth is one of the most promising benefits of hydrogen fuel cell technology when it comes to military applications.
While GM and TARDEC have conducted a great deal of testing from measuring acoustic signatures to how much power and torque is needed to speed up a steep incline, the important feedback will come from soldiers using the demonstrator in operational scenarios over the course of 2017.
The vehicle’s electric motor is nearly silent, whether it’s idling or roaring up a hill. It can export 25 kilowatts of continuous power — 50 kilowatts at its peak — and can produce up to 2 gallons of water per hour (although the water feature is not included in the ZH2 demonstrator). The on-board fuel cells can support long missions of about 300 to 400 miles without needing to be recharged, and the vehicle can use any kind of power from JP-8, solar, water, natural gas or other petroleum-based fuels to generate hydrogen.
Soldiers will see how the hydrogen-powered truck fares compared to other military trucks by conducting reconnaissance and silent watch-type operations and will also examine how technology might be used to power such infrastructure like a mission command post or a field hospital set up in the middle of nowhere, Brian Butrico, TARDEC’s program manager and chief engineer on the ZH2 project, told Defense News.
And the soldiers will see what it’s like to manage the technology from a logistics standpoint like using JP-8 in the field to produce hydrogen, how to store it and how to transport it.
Taking the ZH2 through the paces will provide insight in terms of how the capabilities help soliders' missions and what might be improved.
At the end of the demonstration period in 2017, the hope is to have an idea whether the technology is “really worth pursuing,” Butrico said. “Obviously from what we know now we think it probably is worth pursuing, but again, we are not the end users so we really want our customer to tell us how to shape future efforts and, the technology, where it goes.”
If all goes well, the next step might be to incorporate the technology into a military vehicle like a Humvee. GM and TARDEC opted to demonstrate the technology using a commercial vehicle first because of the much shorter build timeline.
But applications for vehicles like Abrams tanks and Bradley Fighting Vehicles that use a lot of fuel in idle mode to power on-board equipment hold a lot of promise.
The Army will take the keys from GM on April 10, and then a wide range of soldiers, even potentially other services, will put the ZH2 to the test.
The demonstrator will first go to Eglin Air Force Base in Florida for special forces units to try.
From there, the vehicle will be transported at the end of June to Fort Carson, Colorado, where it will be tested by a wide variety of units from Stryker brigades to armored, light infantry and more special forces. The environment will give the Army a chance to test the technology at high-altitude and rockier terrain, Butrico said.
At the end of August, the ZH2 will be passed to soldiers at Fort Bragg, North Carolina, and then it will be moved to Fort Benning, Georgia, in early September, Butrico said.
Also in September, the ZH2 will make an appearance at Modern Day Marine and will take a turn on the Severe Off-Road Track at Marine Corps Base Quantico, Virginia.
While not yet locked in, according to Butrico, the ZH2 might also undergo evaluations with the Marine Corps and Naval Special Warfare Command as well as the Army’s 25th Infantry Division in Hawaii. Those would likely happen at some point between October and April, he said.
The technology being tested in the vehicle now could expand far beyond such a platform in the future. Butrico said the tech is being incorporated into an unmanned undersea vessel and that there is a hydrogen-powered unmanned aircraft currently in the lab at TARDEC. The technology could also be used for stationary power supply at bases that currently consume a large amount of fuel.
The demonstrations also stand to address some of the misinformation or presumptions about hydrogen fuel cell technology that may have stunted its progression into the mainstream in the past.
“The biggest question that we always get is safety,” Butrico said. “Hydrogen explodes,” but if it’s pure hydrogen, a lighted match would go out, he added. “Pure hydrogen will not ignite. You have to have a pretty optimal combination of hydrogen, oxygen and emission source so that if that ratio is too much hydrogen or not enough hydrogen, it won’t combust.”
Also, a puncture in a liquid fuel tank would leak on the ground close to a vehicle, but hydrogen escapes straight up at 45 miles per hour, Butrico noted.
“There are questions we haven’t even thought of that soldiers are going to come up with,” Butrico said. “We really look forward to that and having them hit us with things that we didn’t expect so we can think about that, consider it and plan for it in the follow-on phase, and not just with this vehicle, but any other vehicle as well.”