The Nuclear Regulatory Commission (NRC) has issued construction permits to Kairos Power for its Hermes Two Demonstration Plant at the Heritage Center Industrial Park in Oak Ridge, Tennessee.

The plant comprises two 35MW molten salt reactors and plans to test the commercial viability of its small modular reactor solution (SMR).

The plant will also host a proposed single 35MW Hermes One Test Reactor, a non-nuclear engineering test unit, and potentially a fuel fabrication facility.

Kairos plans to build on what it learned from its Hermes Low-Power Demonstration Reactor, the first US generation IV reactor, to obtain an NRC construction permit in December 2023.

“The commission’s approval of the Hermes Two construction permits marks an important step toward delivering clean electricity from advanced reactors to support decarbonization,” said Mike Laufer, CEO of Kairos.

The Hermes Two plant will be constructed on land adjacent to the Hermes reactor. Following the two-step Code of Federal Regulation licensing process, Kairos will apply for an operating license, subject to NRC approval, before the plant can initiate operations.

“The licensing basis established with both the Hermes and Hermes Two construction permits will carry forward to future license applications, ensuring the safety of Kairos Power’s deployments while supporting continued innovation and efficiency in the review process,” said Peter Hastings, vice president of regulatory affairs and quality at Kairos.

The SMR company uses a molten-salt cooling system, combined with a ceramic, pebble-type fuel, to transport heat to a steam turbine and generate power.

The approval of construction marks a key milestone for the SMR market and will likely have critical implications for the data center market.

In October, the firm signed a master plant development agreement with Google to develop 500MW across six to seven SMRs. Kairos expects to deploy the first SMR by 2030 and further deployments through 2035.

Speaking to DCD, Laufer said: “The commitment for multiple reactors of the same type has strong alignment for both Google and Kairos because it allows for learning across the multiple projects, bringing down the cost curve for new technologies as they're initially deployed.”

Kairos is one of several SMR sectors that have signed supply agreements with data center firms in 2024.

Last week, Oklo partnered with two undisclosed data center providers to deliver up to 750MW of power.

The deals expand Oklo’s customer pipeline to approximately 2,100MW. This follows previous agreements with Equinix and Prometheus for 500MW and 100MW of nuclear power, respectively.

Before this, AWS signed three agreements with Energy Northwest, X-Energy, and Dominion Virginia to support the deployment of more than 600MW of power across Washington and Virginia.