The Canadian Nuclear Safety Commission (CNSC) says it has completed a combined phases 1 & 2 vendor design review (VDR) of GE Hitachi Nuclear Energy’s BWRX-300 boiling water reactor. The VDR takes place during the design process and gives CNSC an opportunity to provide early feedback. It is an optional service provided by CNSC at the request of a vendor. It does not involve issuance of a licence, or influence subsequent CNSC decisions.
During the three-year review of the BWRX-300, which began in 2019, CNSC examined more than 200 documents and attended technical presentations. It also participated in a week-long evaluation, and sent questions across 19 focus areas.
CNSN says that, overall, GE Hitachi Nuclear Energy showed an understanding and correctly interpreted the intent of regulatory requirements and no fundamental barriers to licensing were identified. However, the review did reveal some technical areas needing further development to better demonstrate adherence to CNSC requirements. These areas should be considered in future licensing applications.
According to CNSC:
- Additional information is needed on severe accident analysis and the corresponding engineered features credited for mitigation.
- More in-depth information supporting radiation protection, human factors, decommissioning, and fire protection is needed in order for the CNSC to determine how these programs will meet CNSC requirements.
- It must also be demonstrated that the BWRX-300 design meets the requirement for two separate, independent and diverse means of reactor shutdown, or else an alternative approach, with justification, is needed.
- Further information is needed on restricting radionuclide release during fuel handling activities.
- Further information is needed on the protective measures for workers in the event of an out-of-core criticality accident.
- A BWRX-300 safety analysis needs to be conducted in accordance with procedures, detailing the technical steps.
CNSC notes that these findings and other technical clarifications are to be considered as feedback to GEH to support future licensing applications (e.g. Ontario Power Generation’s application for a licence to construct). CNSC also notes that design and safety analysis developed during the VDR, and design details, have continued to mature since the review. It says design changes within the scope of the regulatory review must be clearly documented by any applicant and will be re-evaluated as part of any future licensing review.
The BWRX-300 design is a 300 MWe water-cooled, natural circulation SMR with passive safety systems. It is the 10th evolution of GE’s boiling water reactor (BWR), hence the “X” in its name. The design is based on the Generation III+ 1,520MWe ESBWR, which the US Nuclear Regulatory Commission certified in 2014. The BWRX-300 is currently undergoing a Canadian Nuclear Safety Commission Pre-licensing Vendor Design Review and a US Nuclear Regulatory Commission Pre-application design review.
In January, GEH, Ontario Power Generation (OPG), SNC-Lavalin and Aecon signed a contract for the deployment of a BWRX-300 SMR at OPG's Darlington site. In August 2022, the Tennessee Valley Authority began planning and preliminary licensing for potential deployment of a BWRX-300 at the Clinch River Site in Tennessee. In June 2022, Canada's SaskPower selected the BWRX-300 for potential deployment in Saskatchewan in the mid-2030s. In addition, Poland’s ORLEN Synthos Green Energy (OSGE) plans a fleet of BWRX-300s, aiming to deploy the first by 2030. GEH has also begun the design certification process for the BWRX-300 in the UK. In February 2023, Estonia's privately held nuclear energy company, Fermi Energia also chose the BWRX-300 for deployment by the early 2030s.
Image: Cutaway of the BWRX-300 nuclear plant (courtesy of GE Hitachi)