US-based Lightbridge Corporation on 11 May announced it had demonstrated the manufacturing process for three-lobe, six-foot rods using surrogate materials. This demonstration of Lightbridge’s proprietary manufacturing process uses an internally developed and patented high-temperature coextrusion process.
The six-foot length of the surrogate rods is the typical length of the fuel rods used by many small modular reactors (SMRs) now in development and licensing. Future fabrication of high-assay low-enriched uranium (HALEU) rodlets for loop irradiation testing in the Advanced Test Reactor, and ultimately commercial length HALEU fuel rods, will use similar extrusion and casting techniques to create material chemistry and grain structures representative of Lightbridge Fuel™. Performing fabrication development activities with surrogate materials allows Lightbridge to use a broader range of suppliers and is a cost-effective approach as it does not require uranium material.
Lightbridge President & CEO Seth Grae said: “We are pleased to have physically produced these surrogate rods with this demonstration of our high-temperature coextrusion process at a length designed for small modular reactors. We are developing Lightbridge Fuel to enable SMRs to economically load follow, ramping up and down in power as renewables are available, and further enhance the safety of SMRs that utilize natural circulation to maintain core cooling. Lightbridge Fuel can reduce the cost of generating electricity from an SMR, while delivering to both SMRs and large reactors increased power output, safety improvements, and enhanced non-proliferation benefits. Powering SMRs with Lightbridge Fuel can strengthen the business case for deploying large numbers of SMRs, an essential component needed towards delivering upon climate goals.”
Image: Surrogate rod coextrusion billets and components (Credit: Lightbridge)