Decay heat modeling and prediction for the SKB-50 set of experiments

This study focuses on the evaluation of the precision of Monte Carlo simulations for the Decay Heat (DH) generated by Spent Nuclear Fuel (SNF), with the goal of reducing the need for costly and time-consuming experiments. The project, named SKB-50, compares decay heat generated by 50 assemblies from second generation PWR and BWR reactors using UO2 as fuel. The DH is compared between experimental data obtained from the Swedish Nuclear Fuel and Waste Management Company (SKB) CLAB facility’s calorimeter and simulated data using Serpent, a Monte Carlo simulation code. Additionally, a similar research project organized by the Paul Scherrer Institut (PSI) in Switzerland is analyzed, which includes an additional assembly. An inventory of the main fission products that contribute to decay heat over a period of more than 30 years is obtained from all these simulations. The study also benchmarks multiple codes against each other to assess their accuracy. These results provide valuable insights for nuclear waste management and can help in the development of more efficient and cost-effective approaches to the management of spent nuclear fuel.