Oklo tests fuel assembly at DOE lab

The company worked with Argonne's thermal-hydraulics team and used the lab's test facilities to study how coolant flows through a fuel assembly across a range of operating conditions. The tests measured parameters such as pressure drop and flow distribution, providing data that will benchmark Oklo’s simulations with full-scale performance, the company said.

The testing was done under a US Department of Energy (DOE) Gateway for Accelerated Innovation in Nuclear (GAIN) voucher. The GAIN initiative was launched in 2016 to help businesses overcome critical technological and commercialisation challenges of nuclear energy technologies through a voucher system, giving stakeholders access to the DOE's R&D facilities and infrastructure to support the cost-effective development of innovative nuclear energy technologies.

"These full-scale, prototypical tests are vital in moving us from design into production," said Oklo co-founder and CEO Jacob DeWitte. "The work we're doing through GAIN at Argonne delivers real-world data that will ultimately inform the manufacturing parameters of our fuel-assembly design."

Oklo's Aurora powerhouse is a fast neutron reactor that uses heat pipes to transport heat from the reactor core to a supercritical carbon dioxide power conversion system to generate electricity. Building on the design and operating heritage of the Experimental Breeder Reactor II (EBR-II), which ran in Idaho from 1964 to 1994, it uses metallic fuel to produce electricity and usable heat, and can operate on fuel made from fresh HALEU or used nuclear fuel. The company recently broke ground for its first powerhouse at a site at Idaho National Laboratory.

By combining Argonne's experimental capabilities with Oklo's ability to design and build prototypic Aurora components as part of its design, build, and test cycle, the effort supports the company's cost-effective approach to building large-scale parts for its powerhouses, Oklo said.