Specs | Fuel Cell Technology | FAQ

WARREN, MI - General Motors Corp. and the U.S. Army revealed a diesel hybrid military pickup truck equipped with a fuel cell auxiliary power unit (APU) that could become the model for the Army's new fleet of 30,000 light tactical vehicles by the end of the decade.

The diesel hybrid improves Army fuel consumption by 20 percent over conventional diesels, reduces emissions and provides troops with clean, reliable electrical power. These are crucial elements in helping to transform the Army into a lighter, more mobile military unit. And with fuel transportation costs reaching up to $400 a gallon depending on training or battlefield operations, the taxpayer savings could run well into the millions of dollars.

GM COMBATTThe 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.

"Our prototype truck incorporates advanced diesel hybrid powertrain technology and introduces the military to the flexibility and security of fuel cell electric power," Burns said. "This defense project is a great opportunity to put large numbers of diesel hybrids and stationary fuel cell units in operation in the interest of national security.

"We also anticipate that it will accelerate cost-effective and durable civilian applications of hybrid-electric vehicles and fuel cells. As an early customer, the military will help drive down costs, increase our learnings, and spur the eventual development of a hydrogen-based economy."

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.

"The potential for fuel cell and diesel hybrid technologies are of critical importance for the Army's next generation of tactical vehicles, and General Motors will play a key leadership role in the research and development efforts for transforming the Army's mobility," said Dennis J. Wend, director of the National Automotive Center, coordinator of the U.S. Army's collaborative vehicle research and development.


"In order for the Army to win today's and tomorrow's battles decisively, we must transform to a lighter, more mobile, more fuel-efficient Army, an Army that is rapidly deployed and sustainable anywhere in the world. The fuel cell auxiliary power unit's quiet operation and low heat signature also are vital elements in reducing the visibility of a deployed force."

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.

"The Army owns a lot of trucks - nearly 250,000 of them, which makes it one of the largest fleets in the nation," said Wend. "Three of top four fuel users in the battlefield are trucks. That's why we need to bring the best and brightest from industry, academia and government to engage in significantly increasing the fuel efficiency of the our military and commercial fleets."

GM COMBATTPowerful 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.

GM COMBATT"The fuel cell unit delivers the same amount of power as a conventional generator without broadcasting your presence," said Burns. "The energy density of hydrogen and the efficiency of the fuel cell gives the same capability of equal-sized batteries but with six to 10 times longer operation, particularly in adverse temperature conditions. The military recognizes these advantages as being key to its mission-critical operations."

Military applications require absolute reliability and durability, said Hydrogenics president and CEO Pierre Rivard.

"This is a valuable opportunity to demonstrate the capabilities of a fuel cell system in what are sure to be very demanding conditions," Rivard said. "We always derive significant learnings from opportunities like this and rapidly channel these learnings into our product development initiatives. In this way we ensure that when it's time to start producing this fuel cell technology in larger volume, it is in fact the current best available technology."

COMBATT program
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.


GM Diesel Hybrid Truck Vehicle Features

Standard Equipment
Engine Duramax 6.6L (401 CID) Turbo Diesel - 210 hp @ 2750 rpm and 545 lbs.-ft. of torque @ 1800 rpm
Transfer case 2-speed, 2.72 low range
Front suspension H.D. independent torsion bar, 4800 lbs. with jounce shock system
Rear suspension semi-elliptical, leaf springs, load-leveling air bags with jounce shock system
Shock absorbers Bilstein Heavy-Duty Gas-Filled
Skid plates under front differential, engine, electric transmission, transfer case, fuel tank and torque arm
Brakes 4-wheel anti-lock, disc front and rear
Electrical system 12/24 volts
Cab 4-door crew cab
Tires 37 x 12.5R 17LT on-/off-road military tread
Wheels aluminum 17-inch
Rear steering Quadrasteer with 2-wheel and 4-wheel steer mode
Gross vehicle weight approx. 10,000 lbs.

Hybrid System
Drive unit split power Continuously Variable Transmission (CVT) with integral electric A/C induction motors
Batteries 300 volts NiMH battery system
Controls two hybrid controllers - two power inverter modules
Regen braking throttle lift and brake pedal apply
Power take-off mobile electric power - 60 Hz - 120/208 Vac, three phase - 5kw mobile, 15kw stationary, 30kw peak
silent watch capable for limited duration

Fuel Cell System
Fuel cell power module Hydrogenics FCE-5G1.1 - 24 to 28 Volts, 6kw peak power
Fuel storage metal hydride low-pressure, high-density hydrogen storage
Electrolyzer Hydrogenics 91E stack, 24-30 volt range, 4kw nominal input power, de-ionized water intake, 50 percent H2 production efficiency
Overall system 5kw net output @ 30 percent "round trip" efficiency, 15kwh / 3 hrs @ max power, <8 hrs recharge time,
24-30VDC input, 24-28VDC output

Fuel Economy Improvement
20 percent over conventional diesel systems; 25-40 percent over conventional gasoline systems

"Projected" Vehicle Performance Specifications
(based on untested prototype level hardware)

4-wheel drive
silent watch = up to 5 hrs. on a single charge of hydrogen
maximum continuous speed = 93 mph (150 km/h)
maximum 0-60mph (0-100km/h) acceleration time = 24 sec.
minimum static grade-ability (low range) = 60 percent
minimum side slope operability = 30 percent

Mobile Command Center
Body structure watertight one-piece construction with 30:70 glass-to-resin ratio, .200-inch thick fiberglass lamination, resin core material sandwiched between two layers with gel-coat finish, optional Kevlar material
Hardware one-piece double-walled doors, stainless steel hinges, self-contained amenities, seven-pole junction box w/ AC power, double-walled floor, interior climate control
Components Will-Burt's non-locking heavy-duty pneumatic mast with 50 ft. extension, OSHKOSH 88A365 HID 24-volt lighting system, Coleman Roughneck 13,500 BTUH rooftop air-conditioner, external area surveillance infrared night-vision camera, security touch pad, AC/DC refrigerator/freezer
Communications Raytheon First Responder Command and Communication Equipment, virtual incident scene mapping, virtual weather modeling, radio interoperability, wireless LAN plus video link, cell phone, satellite uplink plus Globalstar

Military Equipment
- front-mounted 12,000 lb. winch with remote control and storage box
- combination bead lock and run-flat system
- fire extinguisher
- front and rear tie-downs
- tow pintle hook and trailer light hookup
- M16/M14 weapons brackets - 5 weapons
- heavy duty military bumpers with integrated front winch mount, tie- downs, blackout markers, and grille guards
transmission, differentials, and transfer case vent filters
- Pioneer tool kit
- front and rear NATO slave start receptacles, 24-volt power source
- vehicle mounted high-output auxiliary air compressor
- central tire inflation system with rapid deflate feature
- front smart bar
- lift kit with air assist springs
- heavy duty rear axle
- front helical gear limited slip differential
- front mesh seats
- tri-color camouflage paint


Unit Enhances Military's 'Silent Watch' Capability

The 5-kilowatt regenerative fuel cell auxiliary power unit (APU) with its metal hydride hydrogen storage system is a key component of General Motors Corp.'s diesel hybrid military truck for the U.S. Army.

It opens the door to a new world of flexibility and mobility for the military, and provides an important step toward fuel cell commercialization.

Designed and built by GM's strategic fuel-cell alliance partner, Hydrogenics Corp. - which is 24-percent owned by GM, the APU provides a solution for the Army's increasing electrical power needs in the field while enhancing the military's ability to operate undetected by the enemy.

"This military application of fuel cell technology has the potential to demonstrate valuable benefits and capabilities to an organization that relies on the best available technology for mission critical situations," said Pierre Rivard, Hydrogenics president and CEO. "We are confident that our technology will demonstrate its strengths in a compelling manner."

The hydrogen-powered APU produces electricity quietly with a low temperature signature, zero emissions and better efficiency than the conventional generators powered by internal combustion engines, and provides six to 10 times the endurance of battery-based systems of comparable power. The unit is considerably more efficient in cold weather than batteries and eliminates any issues related to toxicity and recycling.

The Army increasingly relies on the operation of surveillance, computer and communications electronics in the battlefield. Typically, the electricity to power this equipment must be provided by either operating the engine or by storage batteries. In a "silent watch" mode, the engine cannot be operated without the vehicle being detected, and battery technology alone cannot provide sufficient energy for the extended operating times required.

The APU also has lower maintenance costs since fuel cell systems have very few moving parts. Internal combustion engines are subject to considerable wear and tear, and require regular operational checks, lubrication and parts replacement.

The APU's design relies on the regenerative, or reversible, properties of proton exchange membrane (PEM) fuel cell technology. While the vehicle is driving, engine-produced electricity operates a PEM electrolyzer unit, which breaks down water into hydrogen and oxygen. The hydrogen is stored in a metal hydride solid material, GM's first application of a solid-state storage device. When the vehicle's engine is off, the hydrogen is combined with oxygen from the air and fed to a fuel cell unit to generate electricity, with water as a byproduct. The water is stored to repeat the cycle.

The storage unit provides enough gaseous hydrogen to operate for three hours at a peak power of 5kw, or five hours at an average output of 3kw. An external hydrogen fuel supply is not required.

Hydrogen for the APU is stored at low pressure and released at low temperature in a metal hydride container. The metal hydride stores about 1 percent hydrogen gas by weight. The hydrogen is stored very compactly in a space smaller than if the hydrogen were liquefied.

In addition, if the metal hydride were punctured, very little hydrogen would be released at ambient temperatures. The combination of compact storage and inherent safety of metal hydride makes this an ideal technology for military applications.

The APU produces DC power to meet the specifications of the particular applications. In the event that the application requires AC power, the unit's power electronics can be designed to offer this. Such design flexibility makes the APU suitable for a broad range of applications, including backup power, auxiliary automotive and marine power, and off-grid solar power storage.

Hydrogenics Corp. (NASDAQ: HYGS and Toronto: HYG), headquartered in Mississauga, Ontario, is a designer and manufacturer of proton exchange membrane (PEM) fuel cell systems for clean power generation.



Q. What are the other trucks being considered as part of the U.S. Army's COMBATT program?
A. GM Defense will deliver a portfolio of eight militarized prototypes based on the commercial Silverado. In addition to the diesel hybrid, the other vehicles include:

One gasoline-electric parallel hybrid truck, powered by a 5.3-liter Vortec V-8 engine. The four-wheel-drive, crew cab pickup has a 2.4 kilowatt electric, 110-volt outlets for exportable power, and provides up to 12 percent better fuel economy over a straight gasoline-powered pickup.

Two 1500 heavy-duty crew cab pickups, powered by 6.0-liter Vortec V-8s. The four-wheel-drive vehicles also are equipped with the Quadrasteer and an enhanced mobility package for off-road driving.

Two 2500 heavy-duty crew cab pickups, powered by 6.6-liter Duramax Diesel V-8s. The four-wheel-drive trucks also are outfitted for severe off-road conditions.

Two 2500 heavy-duty crew cab pickups, powered by 6.6-liter Duramax Diesel V-8s. These four-wheel-drive trucks have extreme off-road capability.
Q. Any plans to produce any of these vehicles for civilian use?
A. GM already sells the base trucks and intends to offer gasoline-electric parallel hybrid trucks later in 2003 as a 2004 model year product. Of course, some modifications of the commercial product are desired by the military customer.

Q. When will the trucks be delivered to the military?
A. The trucks will be delivered in the third- or fourth-quarter of 2003.

Q. Has GM been awarded a contract to build a new fleet of light tactical vehicles?
A. No. The bid process hasn't begun yet. The Army will evaluate the vehicles before establishing the procurement requirements.

Q. What is COMBATT an acronym for?
A. COMmercially BAsed Tactical Truck. The COMBATT program aims to adapt a modified commercial pickup truck to perform some missions assigned to light tactical vehicles. It leverages commercial technology to reduce the cost of developing and acquiring a light tactical vehicle.

Other goals of the program include taking advantage of the high-volume commercial production lines; cost reduction of spares via commercial distribution; incorporating innovative procurement concepts, such as fleet leasing and contract logistical support; and providing continuous improvement via automotive technology at no cost to the Army.

Q. Does the fuel cell auxiliary power unit (APU) use a GM fuel cell stack?
A. No, but future vehicles will.

Q. Is the fuel cell APU an existing Hydrogenics product?
A. Fuel cell APU technology is in the product development stage at Hydrogenics. This particular unit was built especially for the U.S. Army TACOM (Tank-automotive and Armaments Command) in Warren, Mich. TACOM asked GM to integrate it into a diesel hybrid truck.

Q. How much power does the fuel cell APU provide?
A. It produces 5 kilowatts of electricity, which is roughly enough to power a typical single-family house.

Q. Is a hydride storage system suitable for automotive applications?
A. Yes, but not at the current level of technology. Hydrides are still too heavy and expensive for an automotive application.

Q. Isn't Hydrogenics Corp. a partner of GM?
A. Yes. Hydrogenics is one of GM's strategic fuel cell partners. GM has a 24-percent stake in Hydrogenics and has licensed some of its fuel cell technology to Hydrogenics for certain civilian and military applications.

Q. What vehicles has GM provided to the Defense Department in the past?
A. GM has a long history as a provider of reliable transportation products and components to the U.S. government. In addition to more than 100,000 postal vehicles in use today by the U.S. Postal Service, the Defense Department has purchased thousands of cars and trucks for military use. The principal commercial utility cargo vehicle used by the Army today is the GM truck. Every HMMWV has a GM diesel engine and Hydra-Matic transmission. The standard large army trucks also have Allison transmissions, as does the M-1 tank and most other Army-tracked vehicles, except for the Bradley.



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