Batteries, fuel cells, and other clean energy sources are changing how ships are powered. Now, the STEESMAT and ALL-DC-SHIPS projects are working together to ensure the electrical systems onboard evolve as well.
Through projects like these, the European Union is investing in technologies that support the transition to flexible onboard power architectures suited to the needs of the future fleet. While traditional alternating-current (AC) systems are tailored for ships powered largely by conventional diesel engines, DC-based systems are attracting growing interest for their ability to integrate multiple energy sources more efficiently and reduce unnecessary power conversion.
“The transition to low- and zero-emission shipping requires innovative onboard power systems that are compact, modular and highly efficient. By combining the complementary expertise of ALL-DC-SHIPS and STEESMAT, we are accelerating the adoption of DC power architectures as a commercially viable solution for the future of maritime energy systems.” — Professor Pietro Tricoli, Project Coordinator, ALL-DC-SHIPS, University of Birmingham
Demonstrating innovative solutions
ALL-DC-SHIPS focuses on developing a fully integrated DC electrical architecture for ships that will be demonstrated through real-world testing on a 3000 GT dredger. STEESMAT is developing a medium-voltage DC system based on solid-state transformer technology, along with a low-voltage DC secondary grid and AI-based smart energy management, which will be tested in Energy House on land before demonstration in a commercial vessel at sea.
Through their demonstration activities, the two projects aim to show how DC technologies can improve energy efficiency, reduce fuel consumption and simplify integration of renewable energy sources and storage, enhancing reliability, reducing blackout risks, and supporting the transition to climate-neutral shipping.
“For shipowners, the transition to DC-grids is not simply an electrical design choice. It is a key enabler for integrating low emission energy sources while maintaining the operational flexibility required at sea. By combining advanced technology development with real vessel requirements, the collaboration between ALL-DC-SHIPS and STEESMAT can help close the gap between research and commercial deployment.” — Amin Touat, Senior Electrical Engineer, R&D and Newbuild, PONANT
Advancing the maritime transition in Europe
The shared funding call behind STEESMAT and ALL-DC-SHIPS shows that Europe sees modern ship power systems as a key part of the transition to low- and zero-emission shipping.
As large vessels become more electrified, onboard grids must be able to manage higher power levels, integrate new energy sources and operate safely and efficiently in real maritime conditions. The EU’s investment therefore focuses on full-system demonstrations, helping turn DC ship power from a promising technical concept into a practical route towards cleaner vessel operations.
“The value of DC-based power systems lies in how they can improve energy efficiency while reducing the weight and footprint of onboard equipment. For large vessels, this becomes especially important when integrating batteries, fuel cells and other low-emission energy sources. Through projects like STEESMAT and ALL-DC-SHIPS, and in dialogue with industry stakeholders at arenas such as SMM, we can help clarify what is needed to demonstrate, validate and scale these systems for future ship applications.” — Vanja Storetvedt, Project Manager R&D, Wärtsilä
Shaping industry standards
Beyond technology development, both projects also contribute to the testing, validation and standardisation needed to support wider adoption across the maritime sector.
Standards will be critical if DC-based ship power systems are to move from successful demonstrations to wider commercial use. Common approaches to interfaces, protection, communication, testing and approval can reduce uncertainty for shipowners, yards, technology suppliers and classification societies. Both ALL-DC-SHIPS and STEESMAT aim to support the development of standards and validation pathways needed to make DC ship systems trusted, repeatable and scalable.
Collaborating for change
To strengthen collaboration between industry and research, the projects will jointly host a workshop at SMM Hamburg on 3 September 2026. Titled “Making DC Ships Market-Ready”, the workshop will bring together shipowners, technology suppliers, classification societies and researchers to discuss the technical, regulatory and commercial steps needed to support the transition from AC to DC ship power systems.
“The transition from AC to DC is not something one project, one supplier or one shipowner can solve alone. It requires open discussion between technology developers, shipowners, yards, class societies and researchers about what is technically possible, what is commercially realistic, and what needs to be in place for adoption at scale. That is why we are bringing these projects and stakeholders together at SMM.” — Erlend Bertheussen, Project Manager, Maritime CleanTech.
Consortium partners
STEESMAT: Maritime CleanTech (coordinator), Fraunhofer ISIT, Wärtsilä Norway, Sustainable Energy, Eaton Industries, Université de Technologie de Belfort-Montbéliard, Lappeenranta-Lahti University of Technology, Danfoss Drives, NTNU, The Switch, DNV and the Open Direct Current Alliance.
ALL-DC-SHIPS: University of Birmingham (coordinator), BL!XT Tech, Commissariat à l’Energie Atomique et aux Energies Alternatives, Ponant Explorations Group, DEIF, DEIF Wind Power Technology Austria, Flanders Make, Infineon Technologies Austria, Jan De Nul, KAI Kompetenzzentrum Automobil- und Industrieelektronik, RINA Germany and SINTEF Energy Research.
Disclaimer
Co-funded by the European Union. Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or CINEA. Neither the European Union nor the granting authority can be held responsible for them.