NEW YORK | March 25, 2026
Marsh Risk, a business of Marsh (NYSE: MRSH) and the world’s leading insurance broker and risk advisor, today announced that it secured comprehensive insurance coverage for TerraPower’s Kemmerer Unit 1, the first commercial-scale, advanced nuclear power plant in the US approved for construction by the Nuclear Regulatory Commission.
Backed by leading US, London, and Bermuda insurers alongside traditional nuclear insurance pools and risk-retention vehicles, the placement also marks the first time that a next-generation US nuclear plant has gained direct access to the commercial insurance marketplace. The move paves the way for broader adoption of advanced nuclear technologies to transform the future of clean energy infrastructure.
Located in Kemmerer, Wyoming, TerraPower’s Natrium plant represents a new approach to commercial nuclear energy, combining advanced fast reactor technology with integrated energy storage to deliver safe, flexible, and efficient clean energy. The insurance program provides cover for TerraPower and its partners throughout the construction phase of the power plant, which is expected to commence shortly.
Commenting on the program, Michael Kolodner, US Energy & Power Practice Leader, Marsh Risk, said: “Marsh has worked steadily for 70 years to enhance the insurability of nuclear energy assets. By expanding access to all available capacity and enabling direct underwriting by commercial insurers, we are significantly enhancing the insurability and bankability of next-generation nuclear projects. Nuclear risk is insurable risk, and this insurable risk can now be financed more efficiently by our clients."
Eric Williams, Executive Vice President and Chief Operating Officer, TerraPower, added: “TerraPower is delivering a commercial-scale advanced reactor power plant, and insurance is a key enabler in bringing that product to market. We are excited to see the resounding support from the insurance market for the construction of the first Natrium reactor, as evidenced by the oversubscribed insurance program for Kemmerer Unit 1.”
The Natrium technology features a 345 MWe sodium-cooled fast reactor with a molten salt-based energy storage system. The storage technology can boost the system’s output to 500 MWe of power when needed, as it is designed to keep base output steady, ensuring constant reliability and can quickly ramp up when demand peaks — it is the only advanced reactor design with this unique feature.
The first Natrium project is being developed in the US through a public-private partnership with the US Department of Energy. When completed, the Natrium plant will be the first utility-scale advanced nuclear power plant in the US.
Marsh Risk is a business of Marsh (NYSE: MRSH), a global leader in risk, reinsurance and capital, people and investments, and management consulting, advising clients in 130 countries. With annual revenue of $27 billion and more than 95,000 colleagues, Marsh helps build the confidence to thrive through the power of perspective. For more information, visit marsh.com, or follow us on LinkedIn and X.
US & Canada Media Relations Leader, Marsh Risk & Guy Carpenter
United States
