Kairos Wraps ETU 1.0 Testing

Image: Kairos

Kairos has notched another milestone on the way to deploying its first Hermes molten salt reactor by completing testing on its first engineering test unit.

“With this milestone, we now have the team, the knowledge, and the capabilities needed to successfully deploy Hermes and the iterations that will follow,” Edward Blandford, Kairos cofounder and CTO, said in a release.

The test: Since December, Kairos has been carrying out molten salt operations on its first engineering test unit. To perform the tests, Kairos manufactured 12 tonnes of FLiBe (a molten salt made from lithium fluoride and beryllium fluoride), which is the same material that will eventually be used in the Hermes reactor.

Over the course of the tests, Keiros reached…

  • Temperatures of 675°C
  • A salt flow rate of 3,000 gallons per minute
  • 10 TB of performance data

Up next: It’s a wrap on ETU 1.0. Next comes—you guessed it—ETU 2.0. 

  • The company is already at work building ETU 2.0 in Albuquerque, NM.
  • ETU 3.0, the final iteration of the molten salt test unit, will be built in Oak Ridge by the site of the first Hermes reactor.

Kairos won its construction permit for Hermes—the first non-water-cooled reactor design to receive regulatory approval in more than 50 years—in December 2023, though it’s still waiting on an operating license. Right now, the company is hoping to start up its first Hermes reactor by 2026.

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