In the middle of a desert or other remote military zone, advanced power generation can keep the U.S. Army’s ground vehicles and combat support equipment ready for the demands of duty.
“Our power generation advancements are impressive in terms of the capabilities these technologies enable. The most exciting ground vehicle advancements, including driver-optional capabilities, are all enabled by the vehicle’s power structure, which in turn needs a strong, reliable, well-developed architecture,” Dr. Paul D. Rogers, Director of the U.S. Army Tank Automotive Research, Development and Engineering Center (TARDEC) in Warren, Michigan, said in an interview with Truck & Off-Highway Engineering.
One highly touted example of a robust vehicle architecture is the Chevrolet Colorado ZH2, engineered via General Motors (GM) in collaboration with TARDEC. Designed to perform in extreme off-road environments, the ZH2 is built on a stretched midsize pickup truck chassis that employs a uniquely modified suspension and oversized 37-inch tires.
ZH2’s fuel cells generate electricity from a hydrogen source. That electricity powers the vehicle’s propulsion system and the onboard electronics, while off-vehicle power is provided via an Exportable Power Take-Off (EPTO) unit. The EPTO takes the high-voltage from the fuel-cell stack and converts it to both high- and low-voltage alternating current (AC) to power tools and other equipment.
According to Kari Drotleff, TARDEC’s Program Manager for Fuel Cell Technology, Ground Vehicle Power and Mobility, the ZH2’s exportable power ranges from 25 to 50 kW, providing the capability to power a mobile command center. The demonstrator truck has been undergoing field testing at U.S. Army military bases since April 2017.
“So far the feedback from our users, the soldiers, has been fantastic,” Drotleff said. The evaluations, which are slated to continue through the spring of 2018, address multiple considerations, ranging from acoustic and thermal signatures to stationary power generation.
The follow-up to the ZH2 is the Silent Utility Rover Universal Superstructure (SURUS). This fuel-cell platform is envisioned as both a commercial- and military-use electric vehicle with autonomous driving capability. “TARDEC worked with General Motors to develop the overall vision of the SURUS concept vehicle, including its performance, weight, dimensional targets, and base architecture,” said Drotleff. The concept vehicle extensively uses off-the-shelf and near-term components and technologies.
With a hydrogen storage system capable of providing a driving range of more than 400 miles, SURUS is a prime candidate for field testing. “TARDEC and GM are exploring potential program options to take the SURUS concept vehicle and turn it into a functional demonstrator vehicle,” Drotleff said.
While the automotive industry typically uses nickel metal hydride or lithium-ion batteries to power the electric motors in hybrid-electric and all-electric vehicles, fuel cells are deemed a better choice for powering the electric motors in future military vehicle applications. According to Dr. Rogers, “With the weight of Army vehicles (an Abrams tank can push upwards of 80-ton) and the heavy power draw of our applications (drawing at times kilowatts of power), the power density with batteries just isn’t there yet. That leaves hydrogen tanks fueling fuel cells to generate the electricity.”
Stealthy Hydrogen-Powered Chevrolet Silverado Military Truck Breaks Cover, FOX News, 7 Nov 2018
GM Develops Next-Generation ZH2 Hydrogen Fuel Cell-Powered ruck, Jane's Land Systems, 10 Oct 2018
Chevrolet Silverado ZH2 Concept Surfaces via GM Defense, Motor Authority, 2 Nov 2018
Chevrolet Silverado ZH2 Wants to Be the Military's Next Fuel Cell Truck, Motor Trend, 6 Nov 2018
For Dangerous, Difficult or Demanding Situations, SURUS is Ready, General Motors, 2 Nov 2018
GM Thinks Its Stealthy, Optionally-Manned Truck Platform Could Change the US Army, The Drive, 10 Oct 2017
TARDEC, GM bring SURUS to Smithsonian and SOFIC, TARDEC, 21 May 2018
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