The Department of Energy’s Microreactor Applications Research Validation and Evaluation (MARVEL) microreactor project progresses towards criticality after recently hitting some milestones, DOE said Tuesday.
The MARVEL microreactor project, led by DOE’s Idaho National Laboratory (INL), had its final documented safety analysis approved by DOE’s Idaho Operations Office, INL said in its press release. The lab said this approval is a prominent regulatory milestone needed to authorize the reactor’s configuration for dry criticality.
Dry criticality is when a reactor, with no coolant loaded, reaches a self-sustaining nuclear chain reaction and generates near-zero power, INL said. The lab said it expects to reach criticality by December.
DOE previously approved MARVEL’s reactor preliminary documented safety analysis in February.
Following the regulatory approval, INL reported that it received MARVEL’s primary coolant system at Idaho’s Transient Reactor Test Facility in mid-September. The primary coolant system will be responsible for carrying heat away from the reactor core using a sodium-potassium alloy as a coolant during the full-power operations, INL said.
The primary coolant system (PCS) is a prominent component of a reactor and has a significant role in a reactor’s critical safety and operational system.
“We’re ecstatic to not only have our PCS fabricated, but also to get this important approval from DOE, which allows us to move toward MARVEL’s initial criticality,” Abdalla Abou-Jaoude, the MARVEL microreactor lead, said in the release. “Based on DOE guidance, we are also very open to sharing this approved document with key stakeholders in the hopes that it can serve as a template for industry.”
MARVEL is a sodium-potassium-cooled reactor that is designed to generate 85 kilowatts of thermal energy and 10 kilowatts of electricity.
The MARVEL microreactor project operates outside of DOE’s reactor pilot program, which sought to have at least three test reactors reach criticality by Independence Day earlier this year. DOE has been working on the MARVEL project since the early 2020s.