Highlighting the role of the International Atomic Energy Agency’s (IAEA) Platform on Small Modular Reactors and their Applications, a side event at the recent 66th IAEA General Conference looked at the achievements of the Platform that had been established just a year before.

Developed with the aim of helping member states to better understand SMR technology, its safety and economic competitiveness, it provides a one-stop shop to access the IAEA’s full array of support and expertise. From technology development and deployment (including non-electric applications) to nuclear safety, security and safeguards, the platform uses as reference the IAEA Nuclear Energy Series publications, Technology Roadmap for Small Modular Reactor Deployment and other resources.

While the technology’s safety and economic competitiveness must be fully demonstrated before SMRs can be more widely deployed, the SMR Platform has developed a medium-term strategy aimed at providing support to governments, operators, industry and regulators to address these and related challenges.

“The Platform is a very powerful interdepartmental mechanism, bringing together expertise from across the organisation on SMRs,” said Stefano Monti, Chair of the Platform Implementation Team and Head of the IAEA’s Nuclear Power Technology Development Section.

More than 80 SMR designs are under development in 19 countries and the first SMR units are already in operation in China and Russia. As a result, SMRs, including microreactors (MRs), are expected to play an increasingly important role in helping to ensure energy security as well as supporting the transition to net zero emissions. The technologies thus provide a unique potential to address some of our most pressing challenges, from climate change to sustainable development.

“SMRs are perhaps the most exciting and most watched emerging technology in nuclear power today,” Mikhail Chudakov, IAEA Deputy Director General and Head of the Department of Nuclear Energy, said at the meeting, which took place in September. “Member States from Africa and the Americas to Asia and Europe are developing or interested in deploying SMRs, and in a variety of ways, the IAEA Platform on SMRs and their electric and non-electric applications is helping them to do this effectively, safely and securely,” he added.

Participants at the meeting were given an overview of the latest updates on the Platform, as well as IAEA’s Medium-Term Strategy for SMRs and on the related Nuclear Harmonisation and Standardisation Initiative. Two new publications were also launched, which will provide countries considering SMRs with additional tools.

Advances in Small Modular Reactor Technology Developments is a supplement to the IAEA’s Advanced Reactors Information System (ARIS) that can help countries to identify reactor designs that suit their needs. It provides the latest data and information on SMRs from around the world, including detailed descriptions of almost all SMRs under development or construction worldwide.

Meanwhile, Small Modular Reactors: A New Nuclear Energy Paradigm “addresses the needs of policy makers and relevant stakeholders, covering not only SMR technology and applications but the entire full cycle, including infrastructure and economics,” said Monti.

“The activities pertaining to the safety and security of SMRs are a priority for the Agency,” said Anna Bradford, Director of the IAEA Division of Nuclear Installation Safety. “Particularly, our focus is to ensure that the important innovations introduced by SMRs are fully considered and consistent with current safety, security and regulatory approaches. These activities are well coordinated with all other important aspects of the work of the Agency considered as part of the SMR platform.” The IAEA
expects to publish a Safety Report on the applicability of IAEA safety standards to SMR technologies by the end of 2022.

SMR web portal

Earlier this year the SMR Platform introduced a new web portal, which covers technology development and deployment (including non-electric applications), nuclear safety, security and safeguards as well as fuel, the fuel cycle and waste management. The portal will be expanded to incorporate additional features such as areas for technical working groups, information on national and international SMR projects and programmes. “The portal is designed to serve as a centralised source of information for both external and internal IAEA stakeholders, with different levels of information and data access,” said Monti.

“The IAEA is undertaking important activities on the safety and security of SMRs. For example, we have recently completed the review of applicability of the safety standards to SMRs and other technologies,” said Paula Calle Vives, Senior Nuclear Safety Officer at the IAEA coordinating SMR safety activities. “We have also developed a programme of work to progressively adjust the safety standards so that they better capture the specificities of these new technologies. The Platform portal will enable us to better disseminate this work to member states.”

Some countries are already receiving assistance through the SMR Platform and several cross-cutting task forces have been established to address their needs. One of these is helping to organise an expert mission to Jordan to analyse the economics of using SMRs for electricity generation and water desalination. The IAEA is also supporting Brazil in analysing SMR technologies and market readiness, regulatory issues, and requirements for SMR siting.

“Amid the energy and climate crises, more and more countries are looking at SMRs as an option to improve energy security and reduce greenhouse gas emissions,” Monti said. “The IAEA can help them on this journey, which can begin with a visit to the new portal of the IAEA SMR Platform and then, if desired, by lodging a formal request for Agency assistance.”

Nuclear harmonisation and standardisation

SMRs also feature in the IAEA’s new Nuclear Harmonisation and Standardisation Initiative (NHSI), which held its kick off meeting in June 2022. NHSI is helping to facilitate the deployment of safe and secure SMRs by bringing together policymakers, regulators, designers, vendors and operators to develop common regulatory and industrial approaches to SMRs. The many SMR designs under development worldwide, including innovative reactors that are yet to be licensed and novel methods of modular manufacturing that are new to the nuclear industry, means that deployment of SMRs in time to address climate change is a difficult and complex task.

The plans to establish NHSI were announced earlier in 2022 by IAEA Director General Rafael Mariano Grossi, who said IAEA aims to facilitate the safe and secure deployment of SMRs and other advanced nuclear technologies to maximise their contribution to achieving the goals of Agenda 2030 and the Paris Agreement, including reaching net zero carbon emissions by 2050. “SMRs and other advanced nuclear technologies hold immense promise to help address the climate crisis,” ne noted. “But if countries are to fully benefit from their potential to significantly reduce emissions and provide reliable energy, then some challenges to global deployment must be addressed. That’s what this new initiative is all about.”

The cost advantage of SMRs in part arise from an understanding that prefabricated modules could be produced in factories and assembled on site. However, for this to work across borders, common industrial standards, codes and licensing requirements are needed, so that the same safety standards could apply regardless of the country of installation. A degree of harmony among different national nuclear regulatory approaches will also be necessary.

“On the regulatory side, the aim is to increase regulatory collaboration, to establish common positions on technical and policy issues, to pave the way to greater harmonisation, initially in the pre-licensing phase for SMRs, with an agreed expectation of high levels of safety and security for these advanced designs,” said Lydie Evrard, IAEA Deputy Director General and Head of the Department of Nuclear Safety and Security.

Under the NHSI, IAEA will bring together decision makers from governments, regulators, designers, technology holders, operators and other international organisations under two separate complementary tracks: one for technology holders and operators and another for regulators. These tracks, facilitated by the Agency, will then join up in 2024 under an IAEA framework to further advance the initiative, culminating in roadmaps with concrete action plans.

“For industry, the initiative will seek to provide a list of concrete actions and milestones for technology holders and operators to develop more standardised industrial approaches for design, manufacturing, construction, commissioning and operation of SMRs as well as generic user requirements and criteria,” said Aline des Cloizeaux, Director of the IAEA Division of Nuclear Power.

SMR safety standards

Even before these recent development, IAEA had intensified its work in providing support to member states in the development and licensing of SMRs. IAEA is also reviewing the applicability of IAEA Safety Standards to SMRs and has supported, since 2015, the SMR Regulators’ Forum, in which national regulators discuss approaches to this new technology. In addition, IAEA has completed the review of over 60 safety standards to guide their application to a range of SMRs and innovative technology lifecycles and recently published a new TECDOC – “Approach and Methodology for the Development of Regulatory Safety Requirements for the Design of Advanced Nuclear Power Reactors – Case Study on Small Modular Reactors”.

It proposes a stepwise, technology neutral approach and methodology for the development and adaption of regulatory safety requirements for the design of advanced nuclear power reactor technologies, with a particular focus on SMRs. It aims to support decision making by national regulatory authorities, and is based on integrated risk-informed, objective-oriented, performance-based approaches. The publication identifies and exemplifies the key design features of SMRs to be considered important for the process of development or updating the regulatory safety requirements. The information presented is based on the experience provided by technical experts from member states with experience of regulatory requirements for advanced nuclear power reactor technologies, and particularly for SMR designs.

Russia’s SMRs

The first SMR units have already been deployed in Russia and China.

Russia’s Akademik Lomonosov floating NPP is already supplying both power and heat to the Arctic town of Pevek in Chukotka. It was connected to the grid in December 2019, and at the end of May 2020 began commercial operation. The FNPP comprises a dedicated system of coastal infrastructure to support the Akademik Lomonosov floating power unit, which is equipped with two KLT-40S pressurised water reactors (PWRs), previously used to power icebreakers, with capacity of 35MWe each. The power capacity of the FNPP is 70MW, the heat capacity is 50 Gcal/h. Russian regulator Rostekhnadzor has issued a 10-year licence to nuclear utility Rosenergoatom to operate the Akademik Lomonosov until 2029. It was the lead project of a series of mobile transportable low power units to be sited in the Far North and the Far East to provide energy to remote industrial enterprises, port cities and gas and oil platforms.

Subsequent units will have upgraded larger RITM-200 reactors each with a capacity of 50MWe. China (under contract to Russia) has begun laying the keel of the hull for the first of these upgraded FNPPs. It is due to be delivered to Russia by the end of 2023 for the completion and installation of the reactors and other equipment, which is already being manufactured by Russia’s Atomenergomash. This is the first of four planned FNPP units intended for operation in the waters of Cape Nagleingyn in Chukotka. Russia is also planning to construct a ground-based SMR in Yakutia using an adapted version of the RITM-200. The plant is scheduled to be launched in 2028.

China’s first pebble-bed modular high-temperature gas-cooled reactor (HTR-PM) was connected to the grid in 2021 – as unit 1 of the two-unit pebble-bed modular high-temperature gas-cooled reactor demonstration project at the Shidaowan plant in Shandong province.

Both 250MWt reactors reactors have achieved criticality and will drive a single 210MWe turbine. High-temperature gas-cooled reactors use graphite as a moderator and helium as a coolant. The uranium fuel comprises 6 cm-diameter pebbles, each with an outer layer of graphite and containing some 12,000 four-layer ceramic-coated fuel particles dispersed in a matrix of graphite powder. The HTR-PM follows on from China’s HTR-10, a 10 MWt high-temperature gas-cooled experimental reactor at Tsinghua University’s Institute of Nuclear & New Energy Technology, which started up in 2000 and reached full power in 2003. A further 18 such HTR-PM units are proposed for the Shidaowan site.

China is also constructing another SMR demonstration project at the Changjiang NPP using its ACP100 (Linglong One) PWR. China announced the launch of the project in 2019 – it had been under development since 2010. The ACP100 preliminary design was completed in 2014. The major components of integrated PWR’s primary coolant circuit are installed inside the reactor pressure vessel. In 2016, the design became the first SMR to pass a safety review by IAEA.

Argentina’s Carem25

Argentina is completing construction of its Carem (Central ARgentina de Elementos Modulares) reactor – a domestically-designed and developed 32MWe PWR. As well as relying on passive safety systems, Carem’s entire primary coolant system is contained within the single self-pressurised vessel and uses free convection to circulate the coolant. This eliminates the need for devices such as pumps within the primary circuit and decreases the extent and complexity of the piping system required, as well as reduces the possibility of accidents involving a loss of coolant.

Before work was suspended in 2017, it was in line to be the world’s first operating SMR. The government licensed it as a prototype in 2009. Development started in 1980 by the National Atomic Energy Commission (CNEA) and technology company INVAP and it was first announced in 1984. Progress slowed in the early 2000s but a 2006 government decree made the Carem25 programme a national priority. A second executive order in 2008 made the project directly responsible to the President of Argentina. Initially, Carem25 was expected to start up in 2017, but work was suspended in face of financial and technical problems. However work resumed in 2020.

Argentina intends to build additional units for domestic use and export. CNEA has plans to build a 100MWe Carem reactor near Formosa in Argentina and a larger 300MWe version intended for export. In October 2022, IAEA Director General Grossi visited the Carem25 site during a trip to Argentina, where he also met with Agustin Arbor Gonzalez, President of the Nuclear Regulatory Authority (ARN), to discuss regulatory challenges and the essential role of having a regulatory basis for Argentina’s various projects, including Carem25.

US NRC certifies NuScale SMR

Meanwhile, in August 2022, the US Nuclear Regulatory Commission (NRC) issued a final rule certifying NuScale’s small modular reactor (SMR) design for use in the United States. NRC said certification means the design “meets the agency’s applicable safety requirements”. An application for a NPP combined licence that references a certified design “will not need to address any of the issues resolved by the design certification rule”. Instead, the combined licence application and NRC’s safety review would address any remaining safety and environmental issues for the proposed nuclear power plant. The design certification “approves the NuScale reactor’s ‘design control document’, which is incorporated by reference in the final rule”. This is the first SMR design to be certified by NRC.

Subsequently, in October, NRC also accepted NuScale’s methodology for determining the appropriate size of the Emergency Planning Zone (EPZ) around SMR plant sites. The methodology can now be used to determine an EPZ for the NuScale SMR that provides the same level of protection to the public as the 10-mile radius used for existing US NPPs.

NuScale Power Module (NPM) design is a small PWR that can generate 77MWe of electricity and can be scaled to meet customer needs. The VOYGR-12 power plant is capable of generating 924MWe, and NuScale also offers four-module VOYGR-4 (308MWe) and six-module VOYGR-6 (462MWe) plants and other configurations based on customer needs.

SMR site selection in Romania

In another first, an IAEA team of experts in August concluded a safety review of Romania’s process for selecting the site for a planned SMR, which it hopes could become the first SMR built in Europe. In May, the Romanian Government, through state company Societatea Nationala Nuclearelectrica SA (SNN), announced that it had chosen Doicesti, approximately 90 km northwest of the capital Bucharest, as the preferred site for the SMR, following an in-depth study conducted with a United States Trade and Development Agency grant. Romania is considering construction of a NuScale SMR.

Romania requested the IAEA to conduct a Site and External Events Design (SEED) review mission to assess the process that was followed in choosing the preferred site. This was the first ever IAEA SEED mission to look into site selection for an SMR.

Romania documented the site selection process in a preliminary SNN report, which will be followed by a preliminary Front-End Engineering and Design (FEED) study. The SEED mission said a limited amount of additional work is needed on sensitivity analysis and collection of confirmatory data for the FEED study, together with detailed recommendations on the minimisation of project risks. The team provided some recommendations to support the optimisation of the site selection process and to minimise the risk that the following phases will identify important safety issues that may affect project implementation. In particular, the IAEA team recommended that:

  • All data be collected in a site selection summary report, according to the recommendations issued in IAEA Safety Guide SSG-35, to provide traceable support for later decisions and site evaluation phases.
  • A suitable graded approach be applied for the specific technology selected for the SMR to be deployed, and in accordance with the potential radiological consequences of accidents, to meet overall safety objectives. Guidelines on the IAEA approach to grading were provided.
  • A possible additional data collection phase for the selection process — through light investigation and monitoring — be implemented for the preferred site, as back-up solutions, focused on the most discriminating selection criteria.

“We invited the IAEA SEED mission because it is a priority for us to build in Romania a state-of-the-art SMR project, in full compliance with the highest safety standards,” said Cosmin Ghita, SNN CEO. “With the continued support of the IAEA, our experience in siting and building our first SMR can be used by other countries considering building SMRs. SNN is ready to share our experience on strategic and technical aspects of SMR deployment projects.”

IAEA’s support for SMR development and deployment will clearly be vital as more countries decide to adopt this new technology. The SEED mission shows that this support already goes beyond providing technical advice and organising discussion fora and consultations to undertaking practical activities. It is already playing an essential role in developing the detailed technical data, regulations and safety standards, which will be needed in the coming years.

Author: Judith Perera, Contributing Editor, Nuclear Engineering International