Clean Core's ANEEL^TM fuel for PHWRs: a significant increase in burnup and decrease in spent fuel volume

As demand for carbon-free energy increases, the role of nuclear energy in Canada and abroad will have to expand. The efficient utilization of nuclear fuel in terms of energy extraction per mass (burnup) and volume of generated spent fuel must be further optimized as CANDU refurbishments are completed and new reactors are projected to come online. Thoria-enriched urania has potential in increasing the current discharge burnup realized by natural uranium fuel. Fundamentally, this is done through: i. Leveraging the improved thermo physical properties of Thoria (conductivity and melting point) that results in less fuel cracking. ii. Thoria greater retention of fission gases at high burnup per given temperature that limits fuel internal rod pressure. Clean Core Inc., a Chicago based company, is in the process of testing and demonstrating the use of an evolutionary thorium-based fuel for the Pressurized Heavy Water Reactors (PHWRs). Our HALEU (high-assay low-enriched uranium) and Thorium fuel technology, named Advanced Nuclear Energy for Enriched Life (ANEEL^TM), reduces life-cycle operating costs in PHWR while increasing safety margins. This paper describes the benefits of an open thoria-urania fuel cycle from the point of view of uranium utilization, safety margin and spent fuel volume. Long-term storage of irradiated ANEEL^TM fuel with respect to repository disposal requirements will also be discussed. (author)