Hybrid Truck Features a Fuel Cell Auxiliary Power Unit for Stationary Applications
The fuel cell APU would replace the loud engine- and battery-based stationary generators the Army now uses for field power, thus enhancing the Army's "silent watch" capability, or the ability to operate undetected by the enemy. Fuel cells are much quieter than engine generators and do not give off as much heat, making them less likely to be picked up by enemy heat sensors. The fuel cell unit also familiarizes the military with the next generation of commercially developed fuel cell technology, so that military vehicles could be powered by fuel cells within the next 10 years.
GM unveiled the heavy-duty, militarized version of the commercial Chevrolet Silverado crew cab in a ceremony with Larry Burns, GM vice president of research and development and planning, and U.S. Army Major General N. Ross Thompson III, commanding officer of the Army's Tank-automotive and Armaments Command.
The vehicle was designed and engineered by GM Military Truck Operations, based in Troy, Mich., and incorporates technologies from Allison Transmission Division of General Motors, GM's Fuel Cell Activities organization, and GM's strategic fuel cell alliance partner, Hydrogenics Corp., based in Mississauga, Ontario.
The Army will evaluate the prototype before establishing performance and procurement criteria and opening the bid process. The Army is expected to want 30,000 hybrids by the end of the decade.
GM has a long, proud history of serving the U.S. Army's transportation needs. The automaker has produced about 80,000 military vehicles since the mid-1980s. The truck's military features include Raytheon First Responder command and control equipment, infrared night vision camera and GM's "extreme mobility package" to meet the harshest off-road conditions and payload requirements.
Powerful and efficient
The heavy-duty, four-door pickup is powered by a 6.6-liter Duramax Diesel V-8 engine, which generates 210 horsepower and 545 lbs.-ft. of torque.
The engine is mated to a parallel hybrid electric system for improving urban engine emissions and fuel economy. The system itself can increase fuel economy 25 percent to 40 percent over conventional gasoline trucks.
The hybrid system, under early development by GM for commercial applications, uses a patented split power continuously variable transmission (CVT) with integral electric motors and an energy storage system, to deliver power efficiently to the wheels. The lightweight nickel-metal hydride-based energy storage system weighs a third less and is half the size of lead-acid battery storage systems.
In addition, the diesel-electric hybrid powertrain can operate as a self-contained generator, with the capability of providing up to 30kw "exportable" DC and AC electricity for troop operations in the field. This eliminates the need for separate, less efficient, bulky motor-generator sets typically used.
Clean, reliable and quiet
The fuel cell APU, designed and built by Hydrogenics, is a 5-kilowatt proton exchange membrane (PEM) regenerative fuel cell system capable of producing electricity and hydrogen in remote areas. Today's Army uses extensive surveillance and communications electronics to accomplish its missions on tomorrow's battlefields. These electronics must be powered quietly for long periods of time in a manner that is undetectable by the enemy.
When the vehicle is driven, the PEM electrolyzer uses diesel engine provided electricity to break down water into hydrogen and oxygen, with the hydrogen stored for future use. Later, with the engine off, the stored hydrogen, together with oxygen from the air, is fed to the fuel cell to produce electricity, returning the pure water as a byproduct, which is stored to repeat the cycle.
The regenerative APU thus produces its own hydrogen and the Army does not need to add a new logistics fuel. Any additional water is not a problem since water is already provided to the troops and, in a difficult situation, the fuel cell-produced water is drinkable.
The only sound produced is that of quiet air intake fans, making it perfect for use indoors, in confined spaces or where minimal noise is required. In addition, the fuel cell generates power at relatively low temperatures, removing the risk of enemy detection by heat monitoring devices.
The diesel hybrid truck is one of eight different militarized prototypes based on the Silverado that GM Defense will deliver to the Army later this year as part of the Commercially Based Tactical Truck (COMBATT) program. The program leverages commercial technology to reduce the cost of developing and acquiring a light tactical vehicle, and provides the Army with continuous technology improvement.
(January 9, 2003 )