Nuclear Research & Consultancy Group (NRG) of the Netherlands will conduct a programme of irradiation tests on Ultra Safe Nuclear Corporation's (USNC's) proprietary Fully Ceramic Microencapsulated (FCM) fuel at the High Flux Reactor (HFR) in Petten. The aim of the tests is to demonstrate the safety of the fuel for the 20-year lifespan of the USNC's Micro Modular Reactor.

FCM fuel pellets contain TRISO fuel particles, illustrated here in blue (Image: USNC)

In order to analyse the performance and safety attributes of the fuel, NRG will conduct the testing through a two-stage irradiation process in the HFR. Extensive pre and post-irradiation tests at the Hot Cell Laboratories will also be part of the programme.

"Qualification of our FCM fuel by NRG will constitute a significant step in realising our vision for the MMR and carbon-free power generation," said USNC CEO Francesco Venneri. "NRG has the technical prowess and credibility to test our fuel and we fully expect them to confirm the finding of our internal testing."

"NRG has been supporting the nuclear power industry since 1955 and has extensive experience performing complex irradiations and meeting the strenuous requirements of our clients for successful nuclear technology development," said NRG Commercial Director Vinod Ramnandanlal. "Innovative Generation IV reactors truly have transformative potential and Ultra Safe Nuclear has a leading design."

Seattle, Washington-based USNC describes FCM as a next-generation uranium oxycarbide tristructural isotropic (TRISO) particle fuel design, replacing the 50-year-old graphite matrix of traditional TRISO fuel with silicon carbide (SiC). It says the result is a safer nuclear fuel that can withstand higher temperatures and more radiation. The SiC matrix in FCM fuel provides a dense, gas-tight barrier preventing the escape of fission products, even if a TRISO particle should rupture during operation. The new matrix improves the structural and containment characteristics of TRISO particles, trapping and sealing radioactive fission products permanently, preventing contamination of the environment. The higher-thermal conductivity of FCM fuel allows the fuel pellet to have a flatter temperature profile, lowering peak temperatures in nuclear reactors.

FCM fuel will be used first in USNC's MMR, a 15 MW thermal, 5 MW electrical high-temperature gas-cooled reactor, drawing on operational experience from reactors developed by China, Germany, Japan and the USA. It consists of two plants: the nuclear plant that generates heat, and the adjacent power plant that converts heat into electricity or provides process heat for industrial applications. The USNC system is designed to be simple, with minimal operation and maintenance requirements, and no on-site fuel storage, handling or processing. The MMR uses fuel in prismatic graphite blocks and has a sealed transportable core.

The MMR is at an advanced licensing stage at the Atomic Energy of Canada Limited's Chalk River Laboratories campus in Ontario. The project is a collaboration between USNC and Ontario Power Generation through the jointly owned Global First Power Limited Partnership (GFP). Last month, GFP's application for a licence to prepare a site for an MMR at Chalk River moved to the technical review phase of the Canadian Nuclear Safety Commission's licensing process. GFP plans to build and operate an MMR unit by 2026.

Researched and written by World Nuclear News

Date: Thursday, 24 June 2021
Original article: world-nuclear-news.org/Articles/USNC-fuel-to-be-qualified-in-Dutch-reactor