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NASA Purchases Electrolyzer and Fuel
Cell Stacks From Giner Electrochemical Systems, LLC To Support The Helios
Flying Wing
NASA has placed an order with Giner Electrochemical Systems, LLC (GES), a
specialized research and development firm that develops electrolyzers, fuel
cells and related electrochemical systems, to
purchase four lightweight, high-pressure stacks. GES will provide two fuel cell
and two electrolyzer stacks to NASA in support of the Helios Flying Wing, a high
altitude aircraft designed to stay aloft for six months at a time.
The combination of a
fuel cell and electrolyzer stack forms a regenerative system, in which the
electrolyzer stack will convert water, with the aid of electrical power provided
by the solar panels installed on Helios, into gaseous hydrogen and oxygen. These
reactants, when recombined into water in the fuel cell stack, provide electrical
power to keep the plane aloft overnight, when solar power is unavailable. The
design will utilize two fuel cell and two electrolyzer stacks onboard each
aircraft.
This unique regenerative system will utilize stacks based on GES' proprietary
molded graphite bipolar plate technology and use advanced membrane-electrode
assemblies (MEA’s) developed by GES. These components combine into robust
stacks that operate at pressures up to 400 psi (2758 kPa).
Each 15 kW electrolyzer stack will weigh only 23 pounds (10.5 kg), consuming
only 1450 watts/kg, a power to weight ratio that was thought unachievable only a
few years ago. The electrolyzer stacks will each have a total volume of
less than 4 liters. The stacks each produce
nearly 4000 l/hr of hydrogen and 2000 l/hr of oxygen, allowing for stored gas to
extend the operational time of the fuel cell stack.
The fuel cell stacks will each weigh 24 pounds (10.8 kg), and each will provide
5000 watts of power (462 watts/kg), and have an internal volume of less than 5
liters. For a comparative basis, advanced lithium ion polymer batteries are
only able to produce 150 watts/kg, about one third of the power density of the
fuel cell. The fuel cell stacks will consume 1400 l/hr of oxygen and 2800 l/hr
of hydrogen each, supplied from an electrolyzer stack.
The Helios Prototype recently broke records by flying to an altitude of 96,863
ft (29,523 m), powered by the sun. The planes wingspan is longer than that of a
Boeing 747, weighs less than one ton and utilizes solar power to run its 14
propellers. During the record-breaking flight, the aircraft flew at speeds
ranging from 20 mph to 170 mph (32 kph to 273 kph). Overnight test flights for
the Helios are scheduled to begin in 2003, with an initial goal of a four-day
continuous flight.
The stacks were initially designed, built and tested with funding provided by
NASA, Wright Patterson Air Force Base, and AeroVironment Inc., for NASA’s
Environmental Research and Sensor Technology (ERAST) program.
Contact Information:
Richard J. Lawrance, Director
(rlawrance@ginerinc.com) Phone: (781) 529-0507
Matthew P. Steinbroner, Project Manager (msteinbroner@ginerinc.com) Phone: (781)
529-0536
Giner Electrochemical Systems, LLC
Phone: (781) 529-0500; Fax: (781) 893-6470
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