Prototypes have already been demonstrated for use in laptop computers. The Army should be prepared to take advantage of such investments by evaluating the logistical trade-offs involved in fielding nonbattery power solutions. The evaluation should include timelines for the introduction of fueled system alternatives and estimate the consequent reductions (if any) in battery use. This would permit decision makers to make informed judgments on how operational advantages compare to the added burden.

Predictive modeling must play an important part in mitigating risk through analysis of this opportunity. For example, the miniscenario described above was overly simple, taking no account of duty cycles. With predictive models in place, multiple scenarios can be reviewed. Predictive models will be invaluable in examining alternatives, understanding the impacts of unique operations, and narrowing the standard deviations in complex scenarios.

Tethering a single power source to multiple components, such as weapons, sensors, laser designators, and helmets, presents unattractive human factors issues that must be resolved. On the other hand, the attractiveness of a one fuel cell/one battery solution cannot be denied. One way to reap the benefits of both untethered subsystems and a master central power source is to colocate the batteries with the components that require relatively large amounts of power and energy. These could then be tethered to the central source with quick breakaway connectors to permit recharging from the fuel cell during periods of relative inactivity and unhampered action when the need is greatest.


The one fuel cell/one battery central power approach with satellite rechargeable batteries appears to have great promise. If a detailed analysis justifies its operational value and logistics supportability, it is a candidate for accelerated development.

Hybrids have great potential, both as power sources and, over the longer term, as factors in decisions on centralized vs. distributed power. The packaging of a nonstandard fuel for the fuel cell requires an immediate and thorough analysis of trade-offs. The fuel cell approach can then be pursued in earnest if this screen is passed. To facilitate the analysis, the Army should use predictive modeling to narrow sigmas and evaluate choices.

Efficient fuel cells permitting use of JP-8 or reformed fuels could offer even greater advantages and more relief from the logistics burden, eliminating the need for packaged nonstandard fuels from the supply chain. Combining an air-breathing fuel cell with a rechargeable battery would enable operation in all conditions, but would have to be integrated into a much smaller package than current state-of-the-art to be viable on the battlefield.

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