DoD Competition Offers $1 Million for "Wearable Power"

Jul 11, 2007 3:59 PM
By Mark Valentine, Technical Editor, Power Electronics Technology

With the main goal of reducing the weight of the batteries that service members carry into battle, the Department of Defense (DoD) is sponsoring a competition to develop a wearable electric power system for war fighters. The competition, named the Wearable Power Prize, will take place in the fall of 2008, with prizes of $1 million, $500,000 and $250,000 for first, second and third place, respectively.

The prize objective is a wearable, prototype system that can power a standard warfighter’s equipment but weighs less than half that of the battery load now carried. Individuals or teams must demonstrate their prototype systems under realistic conditions to be eligible for the prize.

As weight reduction is the primary goal, all systems meeting the minimum weight and power requirements are then compared on the basis of weight, with lighter systems considered superior to heavier systems. Systems having equal weight (within 1 gram) are further compared on the basis of form factor, with the thin wearable systems considered superior to thick systems (or systems with greater protrusion).

All components, such as the power generator, electrical storage, control electronics, connectors and fuel, must weigh four kilograms or less, including any attachments. The system must also generate 20 W of average power for 96 hours, including the ability to supply 200 W for occasional 5-minute intervals, according to the rules of the competition. To be eligible, the system is required to provide both 14-V and 28-V outputs.

Due to the nature of the intended operating environment for these units, other obvious guidelines are also applied to the competition. For example, as part of the safety restrictions, no radioisotope or nuclear power sources are permitted. The systems must also be able to operate independent of physical orientation. Furthermore, the systems must be able to operate for a certain period inside a sealed container without direct access to free air.

This poses a greater challenge to air-breathing fuel-cell systems (such as the one featured here) than for sealed battery-based systems. However, fuel cell systems can potentially be engineered to provide greater energy densities than battery-based systems (though the wearable form factor may present an additional obstacle). Such systems are also allowed to use multiple fuel storage canisters during testing, but all necessary canisters contribute toward the four-kilogram weight limit. (Systems that exceed the four-kilogram limit may continue with the test program at the discretion of the government, but are not eligible for prize awards.)

According to the DoD (rules document), future war fighters are expected to carry about nine kilograms of primary batteries to power their electronic equipment. However, this competition could lead to the development of a wearable power system that is lighter, and perhaps even functionally transparent to the user. This could not only reduce the physical and mental workload of the warfighter in combat situations, but also reduce the portable power management constraints placed on the designers of future military electronics.

A public information forum on the details of the competition will be held in the Washington, D.C. area in Sept. To participate in the Wearable Power Prize competition, competitors must register by Nov. 30^th. The latest news relating to the competition can be obtained electronically through an online subscription service.