Comparative analysis on small modular reactor (SMR) with uranium and thorium fuel cycle

• Published in: Nuclear engineering and design Vol. 418; p. 112934
• Main Authors: Amatullah, Amila, Permana, Sidik, Irwanto, Dwi, Aimon, Akfiny Hasdi
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-03-2024
• Subjects: Burn-up; Conversion ratio; Neutron multiplication factor; Small modular reactor; Thorium cycle; Uranium cycle; Thorium cycle; Uranium cycle; Burn-up; Small modular reactor; Neutron multiplication factor; Conversion ratio
• ISSN: 0029-5493; 1872-759X
• DOI: 10.1016/j.nucengdes.2024.112934

•Thorium Fuel Cycle has emerged as an appealing alternative fuel option to enhance SMR performance and safety.•Utilization of thorium fuel cycle requires fissile material initially to produce fissile fuel.•Comparation performance for uranium, uranium–thorium, and thorium fuel cycle on 160 MWt SMR.
The utilization of Small Modular Reactors (SMRs) and micro-reactors holds significant potential advantages. The primary benefits include their smaller size, accessibility to remote regions, and reduced land requirements. One noteworthy SMR is the NuScale Power Module (NPM), which has a thermal capacity of 160 MWt and operates on a 2-year cycle. However, there is a growing interest in exploring alternative fuels to enhance SMR performance and safety, and thorium has emerged as an appealing option due to its superior neutron characteristics and potential for higher fuel efficiency. This research aims to do preliminary research into adapting fuel for a thorium fuel cycle in the integral PWR (iPWR). The thorium cycle excels with an initial neutron multiplication factor of 1.134, almost the same as uranium (1.129). Additionally, the thorium cycle boasts superior neutron flux and Conversion Ratio (CR) in the thermal neutron energy range, enhancing sustainability with an average CR of 0.765, compared to 0.574 and 0.692 for uranium and uranium–thorium cycle. The addition of thorium improves efficiency in converting fertile material into fissile material with an enough criticality, where fuels incorporating thorium have a higher CR (Conversion Ratio). Furthermore, thorium fuel cycle has significantly lower production of plutonium isotopes compared to other fuel cycles. However, it faces a challenge with a high power peaking factor (PPF) of 1.923 at the Beginning of Cycle (BOC), requiring further research for mitigation.