In the sprawling world of climate technology, few ideas look as improbable—or as full of possibility—as putting a nuclear reactor on a commercial ship. That is the bet that a tiny Seattle startup named Emerald Nuclear is making. Today the company announced it has received $2.1 million from The Research Council of Norway to help develop small, advanced nuclear reactors for the shipping industry and offshore power. The money is not enough to build a reactor, but it is enough to move the idea forward in a concrete way: working with Norwegian maritime companies to test how a small, advanced reactor would connect to the power systems on a real vessel. Wesley Deason, a nuclear engineer and Emerald Nuclear’s co-founder and CEO, described the grant as a chance to work shoulder to shoulder with marine partners and prove that their technology can fit into a ship’s electrical and control systems. The company is developing what are known as high-temperature gas reactors—a class of reactor that uses a special encapsulated fuel designed to be physically resistant to meltdown. The fuel, called TRISO, contains tiny uranium kernels surrounded by protective carbon and silicon-carbide layers. It is a design that many nuclear experts consider significantly safer than older types of reactors. The Norwegian grant supports the Marine Nuclear Propulsion System Pilot project, led by the company’s Norwegian subsidiary. It is an early step in a long business plan, but with global shipping producing roughly 3% of carbon emissions, there is huge pressure to find solutions that can actually work at sea.
Shipping is one of the hardest parts of the climate puzzle. The world’s cargo ships move almost everything we buy, and they have traditionally burned heavy fuel oil, releasing carbon dioxide, sulfur, and soot. Some shorter ferry routes are already switching to hybrid-electric power, and many shipping companies are exploring methanol, ammonia, biofuels, and other alternatives. But the climate benefits of those fuels depend heavily on how they are produced and whether they truly replace fossil fuels from well to wake. Nuclear power offers something different: extremely dense, carbon-free energy that can propel a ship for years without refueling. The U.S. Navy has relied on nuclear-powered submarines for more than seventy years, proving that reactors can operate safely in harsh marine environments. What is new is the attempt to make nuclear commercially viable for ordinary vessels, not just warships and icebreakers. A wave of startups and larger companies is now working on small reactors for ships and floating power plants. Emerald Nuclear’s contribution is a 5-megawatt reactor, which translates to about 6,705 horsepower—enough to support specialist offshore vessels and floating power units. The company’s two initial target applications are offshore ships that help build oil platforms and wind turbines or lay deep-sea cables, and floating power plants for remote communities that currently depend on diesel generators.
Bringing nuclear power to the marine environment is not a simple engineering task. There are obvious safety issues, international regulations that do not yet exist for commercial vessels, the challenge of managing nuclear fuel and radioactive waste, and the fact that shipping companies buy and sell vessels far more frequently than utilities replace power plants. A nuclear reactor is not something you can casually resell or relocate across borders. Deason, however, says the company’s entire approach has been designed with these realities in mind. The use of TRISO fuel addresses the safety concern: the fuel particles are so robust that they can withstand extreme temperatures without melting, which makes a catastrophic meltdown far less likely. The company plans to manufacture its reactors at seaside facilities, so ships and floating power plants can easily come in for installation, repairs, or exchanges of fresh and spent fuel. Instead of selling the nuclear systems outright, Emerald Nuclear intends to lease them, allowing customers to swap nuclear power in or out depending on the job and their needs. This leasing model also helps solve the resale problem, because the reactor remains the company’s asset, and the customer is essentially buying power, not taking ownership of a radioactive machine. Regulatory hurdles remain, but early deployments could be limited to a single country’s jurisdiction, which would let the company prove the technology before tackling the complicated international rules needed for worldwide shipping.
The Norwegian partnership is central to the company’s plans. Emerald Nuclear has signed a lease for an engineering center in Norway, where it is designing and building its first prototype—a non-nuclear thermal device that will be used for the Marine Nuclear Propulsion System Pilot project. That prototype is a crucial stepping stone because it allows the team to test heat transfer, control systems, and integration with marine electrical equipment without dealing with radioactive fuel. The company is working with a strong set of partners, including VARD Group, Vard Electro, Island Offshore, the Norwegian University of Science and Technology, Imperial College London, and Maskindynamikk. Together they bring together nuclear technology, ship design, vessel operations, and academic research. The first actual nuclear reactor, named the Gem Microreactor, is planned for construction at the Norwegian University of Science and Technology, with a target completion date of 2030. Emerald Nuclear will integrate equipment from Peregrine Turbine Technologies in Maine to convert the reactor’s heat into electricity. The goal for the first commercial deployment is 2031, on a Norwegian offshore vessel. If that timeline holds, it would be a remarkable achievement for a company that has just five employees and has yet to build its first reactor. But the company is not pretending the path is easy. There is still a mountain of engineering, regulation, and financing ahead before the first reactor can be switched on at sea.
The origin of Emerald Nuclear is itself a story of resilience and unexpected connections. Deason previously worked at Ultra Safe Nuclear Corp., a Seattle company developing reactors for space-based applications. During his time there, a professor from the Norwegian University of Science and Technology approached the company about using its nuclear technology in the maritime sector. That conversation planted a seed, but USNC later declared bankruptcy in October 2024, and the project was dropped. When one door closes, another opens: Deason had developed a relationship with Hallgeir Juliebø, a Norwegian entrepreneur who had consulted with USNC and knew the maritime industry well. In 2024, the two co-founded Emerald Nuclear, with Deason as CEO and Juliebø as chief commercial officer. They also brought in Erlend Haugsbø as head of engineering and testing. The team is small, with most members based in Norway, but it combines nuclear engineering expertise with firsthand knowledge of how the shipping industry operates. The company has previously received an undisclosed amount of funding from angel investors, and the new grant from the Research Council of Norway gives it a solid foundation for the next phase of development. Deason’s background in space nuclear reactors may seem far removed from oil rigs and wind farms, but the underlying challenge is the same: building a compact, reliable, and safe power source in a remote and unforgiving environment.
Emerald Nuclear is not the only company chasing this vision. Core Power, newcleo, and Blykalla are also pursuing nuclear ship propulsion, while Core Power, Westinghouse, Saltfoss Energy, and Prodigy Clean Energy are developing floating nuclear power stations. Russia’s state-owned Rosatom already has nuclear-powered icebreakers and a floating nuclear power plant in operation, proving that nuclear power can thrive at sea, even if its commercial viability outside state-run fleets remains unproven. Deason is also thinking ahead to manufacturing. He hopes to open a production site in Western Washington on Puget Sound in the early 2030s, with an initial focus on floating nuclear power systems that could replace diesel generators. That would be a fitting homecoming for a Seattle startup whose founders have deep ties to the Pacific Northwest and to the less glamorous work of industrial engineering. The road from a $2.1 million grant to a working reactor at sea is long, and the company’s success is far from guaranteed. But the ambition is not just to build a gadget; it is to reimagine how the maritime world gets its power. If it works, the payoff is significant: a meaningful reduction in the carbon footprint of global trade, cleaner construction and maintenance of offshore infrastructure, and a reliable source of electricity for remote coastal communities. For now, the team is focused on the next small steps—building the prototype, working with Norwegian partners, and proving that an idea born from an abandoned project can become something durable and real.
