What should countries, regulators and operators consider when planning and implementing emergency preparedness and response (EPR) programmes for next generation reactors (NGRs)? What lessons can they learn from previous experiences with existing reactors, and what new challenges or concerns might emerge? These were among the questions discussed at a recent technical meeting at the IAEA headquarters in Vienna, Austria on next generation reactors and emergency preparedness and response.
“The emergency preparedness and response considerations for these new technologies call for a multi-hazard approach. We need to consider aspects specific to the design, deployment and operation of these new technologies, from both a nuclear safety and nuclear security perspective, to better inform decisions on needed emergency arrangements,” said Frederic Stephani, Incident and Emergency Assessment Officer with the IAEA.
Over the past four years, the IAEA has held a series of technical meetings on emergency preparedness and response as it relates to ‘next generation reactors’: innovative nuclear reactor designs under research and development, including those recently deployed or intended for near term deployment. This meeting was the latest in the series, which concentrates on the safety of NGRs, specifically: how safety improvements may impact emergency preparedness and response arrangements for these reactors and the applicability of specific emergency preparedness and response IAEA safety standards for these reactors.
As the world seeks to find low-carbon sustainable replacements for aging fossil-fuel-fired plants, global interest in NGRs, such as small modular reactors (SMRs) and micro-reactors, as part of a hybrid energy system, is growing. SMRs are advanced reactors that produce up to 300 MW(e) of electricity per module and micro-reactors comprise a subset of SMRs designed to generate electrical power typically up to 10 MW(e). The foreseen advantages of these reactors include greater affordability, shorter construction time, flexible application and smaller environmental footprints.
SMRs’ lower costs and more flexible siting characteristics are advantageous for both countries with established nuclear power programmes and countries that are just embarking on their nuclear programme. In these novel reactors’ safety in all aspects, including emergency preparedness and response, is a crucial consideration.
“Embarking States’ interest in SMRs hinges on, their inherently simpler designs, transportability and enhanced safety margins which allow for customized EPR arrangements,” said Emmanuel Mulehane Acholla, a geologist with the Nuclear Power and Energy Agency in Kenya and participant in the recent technical meeting. “However, in line with existing national regulations that are based upon large nuclear power plants, there is still a need to critically evaluate hazards specific to SMRs and to be well-informed about the appropriate EPR arrangements.”
Participants highlighted the importance of applying a graded approach, based on the results of hazard assessment, to informed decisions on the required on-site and offsite EPR arrangements. This includes the zones or areas in which protective actions need to be taken. “Another point raised in the meeting was public communication: the results from the hazard assessment can be used to communicate with the public in embarking countries on the protection strategy and how associated arrangements provide for public protection,” Acholla said.
There are currently over 70 small modular reactors’ designs at various developmental stages, and several existing and embarking nuclear energy countries are considering these emerging nuclear technologies.
The emergency preparedness and response considerations for these new technologies call for a multi-hazard approach.
NGRs and potential challenges for effective EPR
Next generation reactors differ from existing reactors in several ways which are relevant for emergency planning. For instance, designs currently under consideration are expected to reduce or delay the release of radioactive material in emergencies, which significantly contributes towards enabling a more effective emergency response. The use of novel materials and technologies may give rise to other non-radiation related hazards such as chemical leaks or fires that will eventually have implications on how best to respond in such circumstances; the reliance on new technologies such as cloud-based platforms and remote computing are likely to give rise to security concerns; and the modularity and compactness inherent to small modular reactors may have safety implications. For instance, these reactors are envisioned to share interconnections that strengthen the availability and reliability of support services and personnel; however, some dependencies require specific consideration in emergency planning.
While SMRs and micro-reactors are designed in a way that makes them advantageous, there are also hurdles to overcome regarding emergency preparedness and response. For instance, some of these reactors or their components are designed to be easily transportable when loaded with fuel, which might be an advantage, but also raises concerns about efficiently protecting the public along the transport route.
Additionally, the unique design possibilities of SMRs allow them to be installed in more densely populated areas than existing reactors; however, this imposes a challenge to operators and authorities in term of how they work with surrounding communities to address the public’s safety concerns and conduct regular emergency exercises with all members of the community. Other SMRs are planned to bring electricity to remote communities: emergency planners need to consider scenarios where the reactors are operated a great distance away from the nearest hospital or other emergency service that are essential for an effective emergency response.
As countries prepare to take on the emerging challenges in emergency preparedness and response for SMRs, participants agreed on the need for IAEA support in this area and to convening another event to allow countries to share their initial operational experiences and feedback on emergency preparedness and response for SMRs.