Page 8: of Marine Technology Magazine (Jul/Aug 2026)

SUBSEA DEFENSE

THE POWER OF

PERSISTENCE:

Hydrogen Fuel Cells May Hold the Key to Subsea Endurance

Credit: Cellula Robotics

By David Strachan, Strikepod Systems “Infantry wins battles. Logistics wins wars.”

This quote, attributed to U.S. Army General John Persh- ing in the context of World War I expeditionary operations, is equally applicable today as we move further into the era of autonomous undersea systems. From the age of sail to the nuclear age, maritime power has been underpinned by how far and how long forces could operate forward, and while lo- gistics has traditionally meant sustaining crews and platforms with fuel, food, and materiel, the logistics burden of autono- mous underwater operations increasingly centers on one fun- damental requirement: energy. It is energy that powers every onboard system – propulsion, navigation, communication, and autonomy – and ultimately enables the mission-critical endurance necessary to maintain a persistent subsea presence.

For years, the dominant underwater power paradigm has

General Atomics’ been stored energy. With their high energy density, scalability,

G-Ray and mature manufacturing base, lithium ion (Li-ion) batteries have been the standard for underwater systems for defense and commercial customers alike. But Li-ion’s long-standing domi- nance could be giving way as onboard energy production, in the form of hydrogen fuel cells, is steadily gaining traction.

While a relatively new innovation for autonomous underwater operations, hydrogen fuel cells have been employed by crewed submarines for years to provide air-independent propulsion (AIP; also referred to as air-independent power). Conventional diesel-electric submarines must periodically snorkel to draw oxygen into their diesel engines, which in turn drive genera- tors that recharge the batteries. But snorkeling makes a subma-

Credit: General Atomics 8 July/August 2026

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