US microreactor prototype prepares for testing

23 May 2023

The full-scale replica of the US Department of Energy's (DOE) MARVEL microreactor has been moved from Idaho to a facility in Pennsylvania where it will be used to test the behaviour of sodium-potassium and lead-bismuth coolants.

PCAT was loaded onto a truck for its journey from Idaho to Pennsylvania (Image: INL)

The non-nuclear prototype - known as the primary coolant apparatus test (PCAT) - was built at Idaho National Laboratory (INL) and has now been installed at Creative Engineers, Inc's (CEI) facility in Freedom, Pennsylvania,  where it will be loaded with sodium-potassium and lead-bismuth coolants for testing to gather data on the system's temperatures and coolant flow. The PCAT will be electrically powered during testing, which DOE said could begin as soon as July.

The Microreactor Applications Research Validation and Evaluation (MARVEL) sodium-potassium-cooled microreactor will generate 100 kW and is expected to begin operation at INL's Transient Reactor Test Facility by the end of 2024. It will be used to develop regulatory approval processes, test microreactor applications, evaluate systems for remote monitoring, and develop autonomous control technologies, and to explore and test microreactor capabilities for applications such as thermal storage, water purification and district heating. It will also be connected to INL's first nuclear microgrid.

The non-nuclear prototype has been installed into a two-story frame at CEI's facility (Image: INL)

"Validation of our physics models is critical to nuclear quality assurance for any new reactor development project," MARVEL Chief Design and Project Lead Yasir Arafat said: "PCAT will generate this first-of-a kind-data for validating our thermal-hydraulics simulation tools and quantifying uncertainty for liquid metal thermal reactors, like MARVEL."

The PCAT system is likely to remain at CEI to provide further simulation and testing until the MARVEL microreactor itself begins operation, after which it may be returned to INL to be used for additional research to help advance microreactor technologies.

Fabrication of long-lead components are already underway for the MARVEL microreactor, which DOE said will be the first new test reactor at INL in more than four decades.

Researched and written by World Nuclear News