Small Modular Reactors and Nuclear NonProliferation; to What Extent will the Global Spread
of SMRs Impact Nuclear Proliferation?

The concern about proliferation risks associated with the development and deployment of small modular reactors (SMRs) may be historically motivated. For instance, small power reactors have been used to produce fissile material for weapons. Moreover, the nuclear industry started with small machines that bulked up over the years to take advantage of economies of scale. The Shippingport nuclear plant in Pennsylvania operating in 1957 had a power capacity of 60MW. Similarly, many of today’s SMR plans have their roots in naval reactor technology, such as the Westinghouse reactor that powered the first US nuclear submarines. This article studies the proliferation risks of SMRs, based on review of existing literature, models in development, estimates of future market outcomes and detailed review of published information of selected SRM designs. However, there remains uncertainty over the extent to which widespread SMR use might increase or decrease non-proliferation risk. On the one hand, some SMRs require less frequent refueling than conventional nuclear reactors, thereby mitigating some risk scenarios. Conversely, more integrated designs may be more challenging to inspect, and some designs use more highly enriched uranium than conventional nuclear reactors. Both aspects could increase proliferation risk. Ultimately, SMR proliferation risk depends on both technical and non-technical factors such as which SMRs are deployed in which locations. As such, narrow cost-effectiveness analyses for particular locations may be needed to assess factors including the location’s nuclear regulatory requirements, the customer profile, reactor size, and technology readiness. Consequently, the IAEA safeguards system will have to adapt its financial and personnel capacity to cope with the additional workload arising from the number and variety of SMRs. For instance, it has been estimated that about 85 GW SMR capacity could be installed by 2035, comprising perhaps 1,000 small reactors. The article concludes with policy recommendations as to increase funding allocations in line with the expected rise in SMR deployment, to facilitate collaboration between inspection authorities and SMR developers to fix gaps that can delay safeguards, to improve non-technical factors such as governance in plausible deployment regions and to preempt risks by addressing SMR-specific safeguard issues ahead of time.