Around the world, countries are turning to nuclear energy to mitigate climate change and to improve energy security. Novel reactor designs are entering the scene, along with new modular manufacturing methods, all of which provide opportunities and challenges for deployment. An IAEA initiative is finding common ground among regulators, designers, operators and other stakeholders to support the safe and secure deployment of these advanced reactors, including small modular reactors (SMRs).
The Nuclear Harmonization and Standardization Initiative (NHSI), launched in 2022, is actively developing a series of tools and publications to help advanced reactors become part of the solution addressing climate change and energy security. On Tuesday, more than 120 NHSI participants convened, in person and virtually, to take stock of progress since last year's inaugural meeting and to set priorities for the year to come. By making progress towards harmonizing regulatory approaches and standardizing industrial approaches, NHSI aims to support the timely deployment of advanced reactors to maximize their contribution to reach net zero goals. Technical publications and toolkits are expected to be available by the end of 2024.
NHSI participants work in two separate but complementary tracks: the NHSI Regulatory Track and the NHSI Industry Track. Both tracks have topical working groups, and over the past year, both held 16 working group meetings.
IAEA Director General Rafael Mariano Grossi outlined the benefits of NHSI's work. Harmonization of the regulatory process reduces uncertainty, and it helps to lower the cost of building and deploying SMRs, he stated in his opening remarks. "When it comes to the design of SMRs, working towards global standardization of approaches - by developing international generic user requirements, for example - could increase trade and create economies of scale for manufacturing, construction and operation," he added. Read Mr Grossi's here.
A global review framework
Regulatory Track participants have produced approaches that will help countries to work together in SMR regulatory reviews, sharing resources and knowledge. "The implementation of these approaches will help regulators to learn from each other, increasing their trust that other regulatory frameworks that may initially seem different, are able to achieve good results," said Paula Calle Vives, Senior Nuclear Safety Officer at the IAEA. In addition, the IAEA is planning to gather feedback on the implementation of these approaches and is investigating options for developing a repository of information on regulatory reviews. "The work we are doing is not necessarily aiming to harmonize regulatory requirements but to harmonize how the requirements are met and demonstrated," said Anna Bradford, Director of Nuclear Installation Safety at the IAEA and Chair of the Regulatory Track.
One of the three working groups in the Regulatory Track aims to develop a process to leverage other regulators' reviews to save resources and learn from the expertise and experience of other regulators. It is also developing a process for regulators to collaborate and share their perspectives on reviews of the same nuclear reactor design. Most participants expressed support for avoiding duplication of regulatory reviews.
"We are on track to develop approaches to enhance national reviews, enabling regulators to take maximum advantage of international work and efforts by other regulators. This will lead to minimal repetition among regulatory reviews by different Member States and minimal need for design changes arising from regulatory differences. Together we can establish a common basis for Member States' regulatory decisions while preserving their sovereignty," Mr Grossi said.
Standardized industrial approaches
For the nuclear industry, NHSI is identifying common approaches on codes and standards used as a part of design, manufacturing, construction, commissioning and operation of advanced reactors, like SMRs. "The SMR business model is often based on serial production, which means that after the deployment of the first-of-a-kind reactor, cost and time savings materialize under a standardized approach," said Aline des Cloizeaux, Director of Nuclear Power at the IAEA and Chair of the Industry Track.
One of the main objectives of the Industry Track is to harmonize high-level user requirements. An international reference is under development to help regulatory bodies understand what future licensees expect and to help embarking or expanding nuclear power countries structure their specifications for prospective suppliers.
The Industry Track is also forming a network and associated platform for resource sharing on experiments and code validation for SMRs. The IAEA Network for Experiment and Code Validation Sharing (NEXSHARE) is expected to launch next year, in conjunction with a workshop and publication on participating experimental facilities. "Sharing information on experiment and code validation does not necessarily mean sharing data but identifying what is available, what work is being conducted, what are the gaps and what facilities are currently available," des Cloizeaux said.
Regulatory and industry representatives shared feedback and suggestions on the work that has occurred, thus far, and possible areas for enhancement going forward. The timeliness and relevance of NHSI's work, which will be beneficial for both mature and embarking nuclear power countries, is underscored by the need to transition to clean energy and to meet energy demands. "NHSI can be a game changer if we all work together and commit our resources to bring it to a successful outcome," Mr Grossi said.
NHSI is composed of 30 countries, 94 unique organizations and more than 200 contributors. The next NHSI plenary is planned for 2024.
