urbine and generator at the Teollisuuden Voima Olkiluoto 3 power plant. LEHTIKUVA


The Radiation and Nuclear Safety Authority of Finland (STUK) has joined forces with the nuclear safety authorities of France and the Czech Republic (SÚJB and ASN) to evaluate the safety solutions designed for Small Modular Reactors (SMRs). This assessment was conducted in anticipation of future licensing procedures and was not related to any specific reactor's licensing in Finland or elsewhere.

Finland is currently in the process of renewing its nuclear energy legislation and complementary regulations and guidelines issued by STUK. One of the key objectives of this effort is to streamline the licensing of new types of nuclear power plants. Collaborating with French and Czech authorities provided crucial insights into the suitability of current regulations and guidelines for assessing the safety of small nuclear reactors. Finland's existing rules were primarily designed for large electricity-producing reactors, making some requirements less applicable to smaller-scale reactors.

The French and Czech authorities that participated in this assessment have regulations and guidelines closely aligned with Finland's, and both countries are working towards enhancing their legislation to better accommodate the unique characteristics of SMRs. The International Atomic Energy Agency (IAEA) has also been exploring how safety assessments conducted by different countries' nuclear safety authorities can be leveraged in other countries' licensing processes.

Eero Virtanen, Principal Advisor for STUK, who oversaw the assessment project, emphasized that this endeavor provided valuable experience in conducting collaborative assessments across various authorities. Additionally, it allowed for a deeper understanding of a specific SMR plant. Although the primary goal was not to harmonize requirements among different nations, the project aimed to assist plant designers in developing solutions acceptable in several countries.

All participating authorities initiated the assessment based on their existing national legislation. Virtanen explained, "All participants gained insight into the regulations and guidelines of the participating countries, the rationale behind these requirements, and the licensing procedures."

The assessment focused on the NUWARD SMR plant developed by the French energy company EdF. EdF intends to construct nuclear power plants using this reactor type in France and submitted documentation for evaluation during the pre-licensing phase in France. Evaluated topics included safety design requirements, initiating events used as design foundations, the utilization of passive systems in safety functions, and the advancement of software used in safety analyses.

Ongoing discussions are exploring the possibility of continuing the preliminary assessment of the NUWARD SMR facility with new topics. There is also interest from radiation and nuclear safety authorities in other countries to participate in this assessment, signifying the collaborative nature of enhancing nuclear safety standards for small reactors.