US Defence Department launches hydrogen-powered future for naval forces

Nearly 180 years after the invention of the first hydrogen fuel cell, hydrogen power is poised for a modern resurgence—this time at sea. The US Department of Defense’s Defense Innovation Unit (DIU) has awarded a contract to Pratt Miller to develop a prototype hydrogen-powered energy system designed for naval vessels.

The initiative, known as the Expeditionary Hydrogen On Ship & Shore (EHOSS) project, represents a major step toward the Pentagon’s long-standing goal of eliminating petroleum-based propulsion from military operations.

According to a statement obtained by Defense One, DIU described the project’s aim as building a tactical “micro hydrogen supply chain” using commercially available components. The system will enable hydrogen generation, storage, and distribution both onboard ships and ashore. In addition to powering onboard systems, EHOSS could recharge the batteries of unmanned aerial vehicles (UAVs), other autonomous equipment, and even provide off-ship energy solutions.

The multi-agency effort includes collaboration with US Indo-Pacific Command, the Marine Corps Expeditionary Energy Office, and research teams from both the US Navy and Army.

Pratt Miller, which has been working with the Army since 2019 on hydrogen-powered military vehicles, will incorporate advanced hydrogen fuel cell technologies into the EHOSS prototype. According to Christopher Archambo, the company's chief engineer for hydrogen fuel cell technology, the Navy system will utilize a proton exchange membrane (PEM) electrolyzer to compress hydrogen gas to 10,152 pounds per square inch (psi)—or 700 bar—a pressure standard suitable for refueling large vehicles and military-grade generators.

The hydrogen will be stored in conformable tanks, a design that allows for flexible integration aboard ships and transport vehicles. This stored hydrogen can be used to power various hydrogen-fueled platforms and recharge operational equipment such as drones.

Central to EHOSS is Pratt Miller’s Flexible Power Conversion Module, which enables the system to draw energy from a single source or from the multiple power systems commonly found on naval ships and battlefields. This adaptability makes the system viable in a range of combat and expeditionary scenarios where conventional fuel supply lines may be compromised or unavailable.

By Vafa Guliyeva