Climate & Energy
Samsung C&T Says It Won EPC Priority on Kairos Reactors; Kairos Never Said So
Published: 2026-09-22
In short
Kairos Power signed a term sheet for up to $100M from Samsung C&T, $70M of it equity, for its Hermes 2 reactor. Samsung says it also won EPC priority.
Mr. Latte's take
The line that matters more than the dollar figure appears only in Samsung C&T's own release: priority on EPC work for Kairos's future commercial plants. Hermes 2 is the first 50 megawatts of a Google agreement worth about 500, so if that priority covers the commercial fleet, Kairos has fewer contractors to play off against each other later. Kairos kept the nuclear island for itself, but its investor has already announced who gets first call on the work outside it.
Of the $100 Million, $70 Million Is Equity
Kairos Power announced on September 21 that it had signed a binding term sheet with Samsung C&T's Engineering & Construction Group. Samsung C&T will provide up to $100 million through a mix of direct investment and in-kind engineering services, subject to regulatory approvals, to help deliver the Hermes 2 demonstration plant in Oak Ridge, Tennessee. A Kairos spokesperson told TechCrunch that the equity portion is $70 million. The remaining amount, up to $30 million, arrives as engineering work rather than cash.
Hermes 2 is a grid-connected 50 MWe reactor that will feed the Tennessee Valley Authority grid. Kairos received its NRC construction permits for the plant in December 2024 and broke ground in April 2026. Its output counts as the first 50 megawatts under Kairos's multi-plant development agreement with Google. TechCrunch reports that Google signed with Kairos in fall 2024 for reactors able to generate about half a gigawatt by 2035.
The two companies were already working together. According to Kairos, Samsung C&T, Kairos and Barnard Construction signed a three-way memorandum of understanding on August 18 to set up an early framework for project execution. The term sheet builds on it.
Two Releases, One Day Apart, Four Differences
Samsung C&T put out its own release in Korea on September 22. It describes the same deal, but not in the same terms.
The first difference is what stage the paperwork is at. Kairos announced a term sheet that had already been signed. Samsung C&T said it would sign a strategic agreement on September 23, at a J.P. Morgan event held during Climate Week NYC. The second is the amount. Kairos gave a ceiling of $100 million including in-kind services, while Samsung C&T said it is pursuing an investment of about $70 million and did not break out the services.
The third is the schedule. Samsung C&T's release gives 2031 as the target for bringing the Hermes demonstration reactor online. TechCrunch reported that Kairos expects Hermes 2 to begin operating in 2030. The Kairos release names no year.
The fourth matters most. Samsung C&T said the agreement secures it priority to perform EPC work on the commercial reactors Kairos plans to build in the United States. Kairos's release says Samsung C&T will join the Kairos-led integrated EPC team "alongside other partners" and does not use the word priority at all. Neither release says what the priority covers, how long it lasts or what would end it.
Kairos Keeps the Nuclear Island
On the division of labor, Kairos's release is the detailed one. Samsung C&T's says only that it will take part in design and constructability reviews for the Hermes plant. Kairos says it will lead the reactor technology and the engineering, manufacturing, procurement and construction of the nuclear island. Samsung C&T will support selected engineering and construction work, starting with the power-generation systems and the balance of plant. Kairos's own project management organization keeps control of cost, schedule and execution oversight from development through construction.
That split follows the model Kairos has described for years: vertical integration, where it designs and manufactures core components itself, and iterative development, where each demonstration refines the design. Kairos took the money without giving up the reactor, and handed a large contractor the systems around it first. Samsung C&T's record fits the role. According to Kairos, it has delivered 12 gigawatts across 10 nuclear units, including the Barakah plant in the UAE and Uljin Units 5 and 6 in South Korea.
Find the Word Priority in the Contract
This is the second time this month that a Samsung affiliate has paired a startup investment with an operating relationship. In early September, Samsung Electronics led Mistral's Series D, and its semiconductor division agreed to build chip design and manufacturing models on top of Mistral Large. In the Kairos deal, Samsung C&T gets part of the Hermes 2 scope and, by its own account, priority on commercial EPC work.
For founders, the line to check is the priority clause, not the headline number. Google's agreement with Kairos covers about 500 megawatts, and Hermes 2 is only the first 50. Whoever holds first call on the commercial plants that fill the rest can narrow a startup's options when it later picks contractors and negotiates price. When an investor describes a deal to its shareholders one way and the startup describes it to customers another, the signed document is what counts.
Kairos says the investment is subject to regulatory approvals, and Samsung C&T's signing ceremony is set for September 23. Whether the priority extends to every commercial plant or only to the power-generation and balance-of-plant scope Samsung C&T is taking on is the question the documents that follow will have to answer.
Sources